#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
r""" A JSON data encoder and decoder.
This Python module implements the JSON (http://json.org/) data
encoding format; a subset of ECMAScript (aka JavaScript) for encoding
primitive data types (numbers, strings, booleans, lists, and
associative arrays) in a language-neutral simple text-based syntax.
It can encode or decode between JSON formatted strings and native
Python data types. Normally you would use the encode() and decode()
functions defined by this module, but if you want more control over
the processing you can use the JSON class.
This implementation tries to be as completely cormforming to all
intricacies of the standards as possible. It can operate in strict
mode (which only allows JSON-compliant syntax) or a non-strict mode
(which allows much more of the whole ECMAScript permitted syntax).
This includes complete support for Unicode strings (including
surrogate-pairs for non-BMP characters), and all number formats
including negative zero and IEEE 754 non-numbers such a NaN or
Infinity.
The JSON/ECMAScript to Python type mappings are:
---JSON--- ---Python---
null None
undefined undefined (note 1)
Boolean (true,false) bool (True or False)
Integer int or long (note 2)
Float float
String str or unicode ( "..." or u"..." )
Array [a, ...] list ( [...] )
Object {a:b, ...} dict ( {...} )
-- Note 1. an 'undefined' object is declared in this module which
represents the native Python value for this type when in
non-strict mode.
-- Note 2. some ECMAScript integers may be up-converted to Python
floats, such as 1e+40. Also integer -0 is converted to
float -0, so as to preserve the sign (which ECMAScript requires).
-- Note 3. numbers requiring more significant digits than can be
represented by the Python float type will be converted into a
Python Decimal type, from the standard 'decimal' module.
In addition, when operating in non-strict mode, several IEEE 754
non-numbers are also handled, and are mapped to specific Python
objects declared in this module:
NaN (not a number) nan (float('nan'))
Infinity, +Infinity inf (float('inf'))
-Infinity neginf (float('-inf'))
When encoding Python objects into JSON, you may use types other than
native lists or dictionaries, as long as they support the minimal
interfaces required of all sequences or mappings. This means you can
use generators and iterators, tuples, UserDict subclasses, etc.
To make it easier to produce JSON encoded representations of user
defined classes, if the object has a method named json_equivalent(),
then it will call that method and attempt to encode the object
returned from it instead. It will do this recursively as needed and
before any attempt to encode the object using it's default
strategies. Note that any json_equivalent() method should return
"equivalent" Python objects to be encoded, not an already-encoded
JSON-formatted string. There is no such aid provided to decode
JSON back into user-defined classes as that would dramatically
complicate the interface.
When decoding strings with this module it may operate in either
strict or non-strict mode. The strict mode only allows syntax which
is conforming to RFC 7159 (JSON), while the non-strict allows much
more of the permissible ECMAScript syntax.
The following are permitted when processing in NON-STRICT mode:
* Unicode format control characters are allowed anywhere in the input.
* All Unicode line terminator characters are recognized.
* All Unicode white space characters are recognized.
* The 'undefined' keyword is recognized.
* Hexadecimal number literals are recognized (e.g., 0xA6, 0177).
* String literals may use either single or double quote marks.
* Strings may contain \x (hexadecimal) escape sequences, as well as the
\v and \0 escape sequences.
* Lists may have omitted (elided) elements, e.g., [,,,,,], with
missing elements interpreted as 'undefined' values.
* Object properties (dictionary keys) can be of any of the
types: string literals, numbers, or identifiers (the later of
which are treated as if they are string literals)---as permitted
by ECMAScript. JSON only permits strings literals as keys.
Concerning non-strict and non-ECMAScript allowances:
* Octal numbers: If you allow the 'octal_numbers' behavior (which
is never enabled by default), then you can use octal integers
and octal character escape sequences (per the ECMAScript
standard Annex B.1.2). This behavior is allowed, if enabled,
because it was valid JavaScript at one time.
* Multi-line string literals: Strings which are more than one
line long (contain embedded raw newline characters) are never
permitted. This is neither valid JSON nor ECMAScript. Some other
JSON implementations may allow this, but this module considers
that behavior to be a mistake.
References:
* JSON (JavaScript Object Notation)
* RFC 7159. The application/json Media Type for JavaScript Object Notation (JSON)
* ECMA-262 3rd edition (1999)
* IEEE 754-1985: Standard for Binary Floating-Point Arithmetic.
"""
__author__ = "Deron Meranda "
__homepage__ = "http://deron.meranda.us/python/demjson/"
__date__ = "2015-12-22"
__version__ = "2.2.4"
__version_info__ = ( 2, 2, 4 ) # Will be converted into a namedtuple below
__credits__ = """Copyright (c) 2006-2015 Deron E. Meranda
Licensed under GNU LGPL (GNU Lesser General Public License) version 3.0
or later. See LICENSE.txt included with this software.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see
or .
"""
# ----------------------------------------------------------------------
# Set demjson version
try:
from collections import namedtuple as _namedtuple
__version_info__ = _namedtuple('version_info', ['major', 'minor', 'micro'])( *__version_info__ )
except ImportError:
raise ImportError("demjson %s requires a Python 2.6 or later" % __version__ )
version, version_info = __version__, __version_info__
# Determine Python version
_py_major, _py_minor = None, None
def _get_pyver():
global _py_major, _py_minor
import sys
vi = sys.version_info
try:
_py_major, _py_minor = vi.major, vi.minor
except AttributeError:
_py_major, _py_minor = vi[0], vi[1]
_get_pyver()
# ----------------------------------------------------------------------
# Useful global constants
content_type = 'application/json'
file_ext = 'json'
class _dummy_context_manager(object):
"""A context manager that does nothing on entry or exit."""
def __enter__(self):
pass
def __exit__(self, exc_type, exc_val, exc_tb):
return False
_dummy_context_manager = _dummy_context_manager()
# ----------------------------------------------------------------------
# Decimal and float types.
#
# If a JSON number can not be stored in a Python float without loosing
# precision and the Python has the decimal type, then we will try to
# use decimal instead of float. To make this determination we need to
# know the limits of the float type, but Python doesn't have an easy
# way to tell what the largest floating-point number it supports. So,
# we detemine the precision and scale of the float type by testing it.
try:
# decimal module was introduced in Python 2.4
import decimal
except ImportError:
decimal = None
def determine_float_limits( number_type=float ):
"""Determines the precision and range of the given float type.
The passed in 'number_type' argument should refer to the type of
floating-point number. It should either be the built-in 'float',
or decimal context or constructor; i.e., one of:
# 1. FLOAT TYPE
determine_float_limits( float )
# 2. DEFAULT DECIMAL CONTEXT
determine_float_limits( decimal.Decimal )
# 3. CUSTOM DECIMAL CONTEXT
ctx = decimal.Context( prec=75 )
determine_float_limits( ctx )
Returns a named tuple with components:
( significant_digits,
max_exponent,
min_exponent )
Where:
* significant_digits -- maximum number of *decimal* digits
that can be represented without any loss of precision.
This is conservative, so if there are 16 1/2 digits, it
will return 16, not 17.
* max_exponent -- The maximum exponent (power of 10) that can
be represented before an overflow (or rounding to
infinity) occurs.
* min_exponent -- The minimum exponent (negative power of 10)
that can be represented before either an underflow
(rounding to zero) or a subnormal result (loss of
precision) occurs. Note this is conservative, as
subnormal numbers are excluded.
"""
if decimal:
numeric_exceptions = (ValueError,decimal.Overflow,decimal.Underflow)
else:
numeric_exceptions = (ValueError,)
if decimal and number_type == decimal.Decimal:
number_type = decimal.DefaultContext
if decimal and isinstance(number_type, decimal.Context):
# Passed a decimal Context, extract the bound creator function.
create_num = number_type.create_decimal
decimal_ctx = decimal.localcontext(number_type)
is_zero_or_subnormal = lambda n: n.is_zero() or n.is_subnormal()
elif number_type == float:
create_num = number_type
decimal_ctx = _dummy_context_manager
is_zero_or_subnormal = lambda n: n==0
else:
raise TypeError("Expected a float type, e.g., float or decimal context")
with decimal_ctx:
zero = create_num('0.0')
# Find signifianct digits by comparing floats of increasing
# number of digits, differing in the last digit only, until
# they numerically compare as being equal.
sigdigits = None
n = 0
while True:
n = n + 1
pfx = '0.' + '1'*n
a = create_num( pfx + '0')
for sfx in '123456789': # Check all possible last digits to
# avoid any partial-decimal.
b = create_num( pfx + sfx )
if (a+zero) == (b+zero):
sigdigits = n
break
if sigdigits:
break
# Find exponent limits. First find order of magnitude and
# then use a binary search to find the exact exponent.
base = '1.' + '1'*(sigdigits-1)
base0 = '1.' + '1'*(sigdigits-2)
minexp, maxexp = None, None
for expsign in ('+','-'):
minv = 0; maxv = 10
# First find order of magnitude of exponent limit
while True:
try:
s = base + 'e' + expsign + str(maxv)
s0 = base0 + 'e' + expsign + str(maxv)
f = create_num( s ) + zero
f0 = create_num( s0 ) + zero
except numeric_exceptions:
f = None
if not f or not str(f)[0].isdigit() or is_zero_or_subnormal(f) or f==f0:
break
else:
minv = maxv
maxv = maxv * 10
# Now do a binary search to find exact limit
while True:
if minv+1 == maxv:
if expsign=='+':
maxexp = minv
else:
minexp = minv
break
elif maxv < minv:
if expsign=='+':
maxexp = None
else:
minexp = None
break
m = (minv + maxv) // 2
try:
s = base + 'e' + expsign + str(m)
s0 = base0 + 'e' + expsign + str(m)
f = create_num( s ) + zero
f0 = create_num( s0 ) + zero
except numeric_exceptions:
f = None
else:
if not f or not str(f)[0].isdigit():
f = None
elif is_zero_or_subnormal(f) or f==f0:
f = None
if not f:
# infinite
maxv = m
else:
minv = m
return _namedtuple('float_limits', ['significant_digits', 'max_exponent', 'min_exponent'])( sigdigits, maxexp, -minexp )
float_sigdigits, float_maxexp, float_minexp = determine_float_limits( float )
# For backwards compatibility with older demjson versions:
def determine_float_precision():
v = determine_float_limits( float )
return ( v.significant_digits, v.max_exponent )
# ----------------------------------------------------------------------
# The undefined value.
#
# ECMAScript has an undefined value (similar to yet distinct from null).
# Neither Python or strict JSON have support undefined, but to allow
# JavaScript behavior we must simulate it.
class _undefined_class(object):
"""Represents the ECMAScript 'undefined' value."""
__slots__ = []
def __repr__(self):
return self.__module__ + '.undefined'
def __str__(self):
return 'undefined'
def __nonzero__(self):
return False
undefined = _undefined_class()
syntax_error = _undefined_class() # same as undefined, but has separate identity
del _undefined_class
# ----------------------------------------------------------------------
# Non-Numbers: NaN, Infinity, -Infinity
#
# ECMAScript has official support for non-number floats, although
# strict JSON does not. Python doesn't either. So to support the
# full JavaScript behavior we must try to add them into Python, which
# is unfortunately a bit of black magic. If our python implementation
# happens to be built on top of IEEE 754 we can probably trick python
# into using real floats. Otherwise we must simulate it with classes.
def _nonnumber_float_constants():
"""Try to return the Nan, Infinity, and -Infinity float values.
This is necessarily complex because there is no standard
platform-independent way to do this in Python as the language
(opposed to some implementation of it) doesn't discuss
non-numbers. We try various strategies from the best to the
worst.
If this Python interpreter uses the IEEE 754 floating point
standard then the returned values will probably be real instances
of the 'float' type. Otherwise a custom class object is returned
which will attempt to simulate the correct behavior as much as
possible.
"""
try:
# First, try (mostly portable) float constructor. Works under
# Linux x86 (gcc) and some Unices.
nan = float('nan')
inf = float('inf')
neginf = float('-inf')
except ValueError:
try:
# Try the AIX (PowerPC) float constructors
nan = float('NaNQ')
inf = float('INF')
neginf = float('-INF')
except ValueError:
try:
# Next, try binary unpacking. Should work under
# platforms using IEEE 754 floating point.
import struct, sys
xnan = '7ff8000000000000'.decode('hex') # Quiet NaN
xinf = '7ff0000000000000'.decode('hex')
xcheck = 'bdc145651592979d'.decode('hex') # -3.14159e-11
# Could use float.__getformat__, but it is a new python feature,
# so we use sys.byteorder.
if sys.byteorder == 'big':
nan = struct.unpack('d', xnan)[0]
inf = struct.unpack('d', xinf)[0]
check = struct.unpack('d', xcheck)[0]
else:
nan = struct.unpack('d', xnan[::-1])[0]
inf = struct.unpack('d', xinf[::-1])[0]
check = struct.unpack('d', xcheck[::-1])[0]
neginf = - inf
if check != -3.14159e-11:
raise ValueError('Unpacking raw IEEE 754 floats does not work')
except (ValueError, TypeError):
# Punt, make some fake classes to simulate. These are
# not perfect though. For instance nan * 1.0 == nan,
# as expected, but 1.0 * nan == 0.0, which is wrong.
class nan(float):
"""An approximation of the NaN (not a number) floating point number."""
def __repr__(self): return 'nan'
def __str__(self): return 'nan'
def __add__(self,x): return self
def __radd__(self,x): return self
def __sub__(self,x): return self
def __rsub__(self,x): return self
def __mul__(self,x): return self
def __rmul__(self,x): return self
def __div__(self,x): return self
def __rdiv__(self,x): return self
def __divmod__(self,x): return (self,self)
def __rdivmod__(self,x): return (self,self)
def __mod__(self,x): return self
def __rmod__(self,x): return self
def __pow__(self,exp): return self
def __rpow__(self,exp): return self
def __neg__(self): return self
def __pos__(self): return self
def __abs__(self): return self
def __lt__(self,x): return False
def __le__(self,x): return False
def __eq__(self,x): return False
def __neq__(self,x): return True
def __ge__(self,x): return False
def __gt__(self,x): return False
def __complex__(self,*a): raise NotImplementedError('NaN can not be converted to a complex')
if decimal:
nan = decimal.Decimal('NaN')
else:
nan = nan()
class inf(float):
"""An approximation of the +Infinity floating point number."""
def __repr__(self): return 'inf'
def __str__(self): return 'inf'
def __add__(self,x): return self
def __radd__(self,x): return self
def __sub__(self,x): return self
def __rsub__(self,x): return self
def __mul__(self,x):
if x is neginf or x < 0:
return neginf
elif x == 0:
return nan
else:
return self
def __rmul__(self,x): return self.__mul__(x)
def __div__(self,x):
if x == 0:
raise ZeroDivisionError('float division')
elif x < 0:
return neginf
else:
return self
def __rdiv__(self,x):
if x is inf or x is neginf or x is nan:
return nan
return 0.0
def __divmod__(self,x):
if x == 0:
raise ZeroDivisionError('float divmod()')
elif x < 0:
return (nan,nan)
else:
return (self,self)
def __rdivmod__(self,x):
if x is inf or x is neginf or x is nan:
return (nan, nan)
return (0.0, x)
def __mod__(self,x):
if x == 0:
raise ZeroDivisionError('float modulo')
else:
return nan
def __rmod__(self,x):
if x is inf or x is neginf or x is nan:
return nan
return x
def __pow__(self, exp):
if exp == 0:
return 1.0
else:
return self
def __rpow__(self, x):
if -1 < x < 1: return 0.0
elif x == 1.0: return 1.0
elif x is nan or x is neginf or x < 0:
return nan
else:
return self
def __neg__(self): return neginf
def __pos__(self): return self
def __abs__(self): return self
def __lt__(self,x): return False
def __le__(self,x):
if x is self:
return True
else:
return False
def __eq__(self,x):
if x is self:
return True
else:
return False
def __neq__(self,x):
if x is self:
return False
else:
return True
def __ge__(self,x): return True
def __gt__(self,x): return True
def __complex__(self,*a): raise NotImplementedError('Infinity can not be converted to a complex')
if decimal:
inf = decimal.Decimal('Infinity')
else:
inf = inf()
class neginf(float):
"""An approximation of the -Infinity floating point number."""
def __repr__(self): return '-inf'
def __str__(self): return '-inf'
def __add__(self,x): return self
def __radd__(self,x): return self
def __sub__(self,x): return self
def __rsub__(self,x): return self
def __mul__(self,x):
if x is self or x < 0:
return inf
elif x == 0:
return nan
else:
return self
def __rmul__(self,x): return self.__mul__(self)
def __div__(self,x):
if x == 0:
raise ZeroDivisionError('float division')
elif x < 0:
return inf
else:
return self
def __rdiv__(self,x):
if x is inf or x is neginf or x is nan:
return nan
return -0.0
def __divmod__(self,x):
if x == 0:
raise ZeroDivisionError('float divmod()')
elif x < 0:
return (nan,nan)
else:
return (self,self)
def __rdivmod__(self,x):
if x is inf or x is neginf or x is nan:
return (nan, nan)
return (-0.0, x)
def __mod__(self,x):
if x == 0:
raise ZeroDivisionError('float modulo')
else:
return nan
def __rmod__(self,x):
if x is inf or x is neginf or x is nan:
return nan
return x
def __pow__(self,exp):
if exp == 0:
return 1.0
else:
return self
def __rpow__(self, x):
if x is nan or x is inf or x is inf:
return nan
return 0.0
def __neg__(self): return inf
def __pos__(self): return self
def __abs__(self): return inf
def __lt__(self,x): return True
def __le__(self,x): return True
def __eq__(self,x):
if x is self:
return True
else:
return False
def __neq__(self,x):
if x is self:
return False
else:
return True
def __ge__(self,x):
if x is self:
return True
else:
return False
def __gt__(self,x): return False
def __complex__(self,*a): raise NotImplementedError('-Infinity can not be converted to a complex')
if decimal:
neginf = decimal.Decimal('-Infinity')
else:
neginf = neginf(0)
return nan, inf, neginf
nan, inf, neginf = _nonnumber_float_constants()
del _nonnumber_float_constants
# ----------------------------------------------------------------------
# Integers
class json_int( (1L).__class__ ): # Have to specify base this way to satisfy 2to3
"""A subclass of the Python int/long that remembers its format (hex,octal,etc).
Initialize it the same as an int, but also accepts an additional keyword
argument 'number_format' which should be one of the NUMBER_FORMAT_* values.
n = json_int( x[, base, number_format=NUMBER_FORMAT_DECIMAL] )
"""
def __new__(cls, *args, **kwargs):
if 'number_format' in kwargs:
number_format = kwargs['number_format']
del kwargs['number_format']
if number_format not in (NUMBER_FORMAT_DECIMAL, NUMBER_FORMAT_HEX, NUMBER_FORMAT_OCTAL, NUMBER_FORMAT_LEGACYOCTAL, NUMBER_FORMAT_BINARY):
raise TypeError("json_int(): Invalid value for number_format argument")
else:
number_format = NUMBER_FORMAT_DECIMAL
obj = super(json_int,cls).__new__(cls,*args,**kwargs)
obj._jsonfmt = number_format
return obj
@property
def number_format(self):
"""The original radix format of the number"""
return self._jsonfmt
def json_format(self):
"""Returns the integer value formatted as a JSON literal"""
fmt = self._jsonfmt
if fmt == NUMBER_FORMAT_HEX:
return format(self, '#x')
elif fmt == NUMBER_FORMAT_OCTAL:
return format(self, '#o')
elif fmt == NUMBER_FORMAT_BINARY:
return format(self, '#b')
elif fmt == NUMBER_FORMAT_LEGACYOCTAL:
if self==0:
return '0' # For some reason Python's int doesn't do '00'
elif self < 0:
return '-0%o' % (-self)
else:
return '0%o' % self
else:
return str(self)
# ----------------------------------------------------------------------
# String processing helpers
def skipstringsafe( s, start=0, end=None ):
i = start
#if end is None:
# end = len(s)
unsafe = helpers.unsafe_string_chars
while i < end and s[i] not in unsafe:
#c = s[i]
#if c in unsafe_string_chars:
# break
i += 1
return i
def skipstringsafe_slow( s, start=0, end=None ):
i = start
if end is None:
end = len(s)
while i < end:
c = s[i]
if c == '"' or c == "'" or c == '\\' or ord(c) <= 0x1f:
break
i += 1
return i
def extend_list_with_sep( orig_seq, extension_seq, sepchar='' ):
if not sepchar:
orig_seq.extend( extension_seq )
else:
for i, x in enumerate(extension_seq):
if i > 0:
orig_seq.append( sepchar )
orig_seq.append( x )
def extend_and_flatten_list_with_sep( orig_seq, extension_seq, separator='' ):
for i, part in enumerate(extension_seq):
if i > 0 and separator:
orig_seq.append( separator )
orig_seq.extend( part )
# ----------------------------------------------------------------------
# Unicode UTF-32
# ----------------------------------------------------------------------
def _make_raw_bytes( byte_list ):
"""Takes a list of byte values (numbers) and returns a bytes (Python 3) or string (Python 2)
"""
if _py_major >= 3:
b = bytes( byte_list )
else:
b = ''.join(chr(n) for n in byte_list)
return b
import codecs
class utf32(codecs.CodecInfo):
"""Unicode UTF-32 and UCS4 encoding/decoding support.
This is for older Pythons whch did not have UTF-32 codecs.
JSON requires that all JSON implementations must support the
UTF-32 encoding (as well as UTF-8 and UTF-16). But earlier
versions of Python did not provide a UTF-32 codec, so we must
implement UTF-32 ourselves in case we need it.
See http://en.wikipedia.org/wiki/UTF-32
"""
BOM_UTF32_BE = _make_raw_bytes([ 0, 0, 0xFE, 0xFF ]) #'\x00\x00\xfe\xff'
BOM_UTF32_LE = _make_raw_bytes([ 0xFF, 0xFE, 0, 0 ]) #'\xff\xfe\x00\x00'
@staticmethod
def lookup( name ):
"""A standard Python codec lookup function for UCS4/UTF32.
If if recognizes an encoding name it returns a CodecInfo
structure which contains the various encode and decoder
functions to use.
"""
ci = None
name = name.upper()
if name in ('UCS4BE','UCS-4BE','UCS-4-BE','UTF32BE','UTF-32BE','UTF-32-BE'):
ci = codecs.CodecInfo( utf32.utf32be_encode, utf32.utf32be_decode, name='utf-32be')
elif name in ('UCS4LE','UCS-4LE','UCS-4-LE','UTF32LE','UTF-32LE','UTF-32-LE'):
ci = codecs.CodecInfo( utf32.utf32le_encode, utf32.utf32le_decode, name='utf-32le')
elif name in ('UCS4','UCS-4','UTF32','UTF-32'):
ci = codecs.CodecInfo( utf32.encode, utf32.decode, name='utf-32')
return ci
@staticmethod
def encode( obj, errors='strict', endianness=None, include_bom=True ):
"""Encodes a Unicode string into a UTF-32 encoded byte string.
Returns a tuple: (bytearray, num_chars)
The errors argument should be one of 'strict', 'ignore', or 'replace'.
The endianness should be one of:
* 'B', '>', or 'big' -- Big endian
* 'L', '<', or 'little' -- Little endien
* None -- Default, from sys.byteorder
If include_bom is true a Byte-Order Mark will be written to
the beginning of the string, otherwise it will be omitted.
"""
import sys, struct
# Make a container that can store bytes
if _py_major >= 3:
f = bytearray()
write = f.extend
def tobytes():
return bytes(f)
else:
try:
import cStringIO as sio
except ImportError:
import StringIO as sio
f = sio.StringIO()
write = f.write
tobytes = f.getvalue
if not endianness:
endianness = sys.byteorder
if endianness.upper()[0] in ('B>'):
big_endian = True
elif endianness.upper()[0] in ('L<'):
big_endian = False
else:
raise ValueError("Invalid endianness %r: expected 'big', 'little', or None" % endianness)
pack = struct.pack
packspec = '>L' if big_endian else ' maxunicode or (0xD800 <= n <= 0xDFFF):
if errors == 'strict':
raise UnicodeDecodeError('utf32',obj,i,i+4,'Invalid code point U+%04X' % n)
elif errors == 'replace':
chars.append( unichr(0xFFFD) )
elif errors == 'backslashreplace':
if n > 0xffff:
esc = "\\u%04x" % (n,)
else:
esc = "\\U%08x" % (n,)
for esc_c in esc:
chars.append( esc_c )
elif errors == 'xmlcharrefreplace':
esc = "&#%d;" % (n,)
for esc_c in esc:
chars.append( esc_c )
else: # ignore
pass
else:
chars.append( helpers.safe_unichr(n) )
return (u''.join( chars ), num_bytes)
@staticmethod
def utf32le_decode( obj, errors='strict' ):
"""Decodes a UTF-32LE (little endian) byte string into a Unicode string."""
return utf32.decode( obj, errors=errors, endianness='L' )
@staticmethod
def utf32be_decode( obj, errors='strict' ):
"""Decodes a UTF-32BE (big endian) byte string into a Unicode string."""
return utf32.decode( obj, errors=errors, endianness='B' )
# ----------------------------------------------------------------------
# Helper functions
# ----------------------------------------------------------------------
def _make_unsafe_string_chars():
import unicodedata
unsafe = []
for c in [unichr(i) for i in range(0x100)]:
if c == u'"' or c == u'\\' \
or unicodedata.category( c ) in ['Cc','Cf','Zl','Zp']:
unsafe.append( c )
return u''.join( unsafe )
class helpers(object):
"""A set of utility functions."""
hexdigits = '0123456789ABCDEFabcdef'
octaldigits = '01234567'
unsafe_string_chars = _make_unsafe_string_chars()
import sys
maxunicode = sys.maxunicode
always_use_custom_codecs = False # If True use demjson's codecs
# before system codecs. This
# is mainly here for testing.
javascript_reserved_words = frozenset([
# Keywords (plus "let") (ECMAScript 6 section 11.6.2.1)
'break','case','catch','class','const','continue',
'debugger','default','delete','do','else','export',
'extends','finally','for','function','if','import',
'in','instanceof','let','new','return','super',
'switch','this','throw','try','typeof','var','void',
'while','with','yield',
# Future reserved words (ECMAScript 6 section 11.6.2.2)
'enum','implements','interface','package',
'private','protected','public','static',
# null/boolean literals
'null','true','false'
])
@staticmethod
def make_raw_bytes( byte_list ):
"""Constructs a byte array (bytes in Python 3, str in Python 2) from a list of byte values (0-255).
"""
return _make_raw_bytes( byte_list )
@staticmethod
def is_hex_digit( c ):
"""Determines if the given character is a valid hexadecimal digit (0-9, a-f, A-F)."""
return (c in helpers.hexdigits)
@staticmethod
def is_octal_digit( c ):
"""Determines if the given character is a valid octal digit (0-7)."""
return (c in helpers.octaldigits)
@staticmethod
def is_binary_digit( c ):
"""Determines if the given character is a valid binary digit (0 or 1)."""
return (c == '0' or c == '1')
@staticmethod
def char_is_json_ws( c ):
"""Determines if the given character is a JSON white-space character"""
return c in ' \t\n\r'
@staticmethod
def safe_unichr( codepoint ):
"""Just like Python's unichr() but works in narrow-Unicode Pythons."""
if codepoint >= 0x10000 and codepoint > helpers.maxunicode:
# Narrow-Unicode python, construct a UTF-16 surrogate pair.
w1, w2 = helpers.make_surrogate_pair( codepoint )
if w2 is None:
c = unichr(w1)
else:
c = unichr(w1) + unichr(w2)
else:
c = unichr(codepoint)
return c
@staticmethod
def char_is_unicode_ws( c ):
"""Determines if the given character is a Unicode space character"""
if not isinstance(c,unicode):
c = unicode(c)
if c in u' \t\n\r\f\v':
return True
import unicodedata
return unicodedata.category(c) == 'Zs'
@staticmethod
def char_is_json_eol( c ):
"""Determines if the given character is a JSON line separator"""
return c in '\n\r'
@staticmethod
def char_is_unicode_eol( c ):
"""Determines if the given character is a Unicode line or
paragraph separator. These correspond to CR and LF as well as
Unicode characters in the Zl or Zp categories.
"""
return c in u'\r\n\u2028\u2029'
@staticmethod
def char_is_identifier_leader( c ):
"""Determines if the character may be the first character of a
JavaScript identifier.
"""
return c.isalpha() or c in '_$'
@staticmethod
def char_is_identifier_tail( c ):
"""Determines if the character may be part of a JavaScript
identifier.
"""
return c.isalnum() or c in u'_$\u200c\u200d'
@staticmethod
def extend_and_flatten_list_with_sep( orig_seq, extension_seq, separator='' ):
for i, part in enumerate(extension_seq):
if i > 0 and separator:
orig_seq.append( separator )
orig_seq.extend( part )
@staticmethod
def strip_format_control_chars( txt ):
"""Filters out all Unicode format control characters from the string.
ECMAScript permits any Unicode "format control characters" to
appear at any place in the source code. They are to be
ignored as if they are not there before any other lexical
tokenization occurs. Note that JSON does not allow them,
except within string literals.
* Ref. ECMAScript section 7.1.
* http://en.wikipedia.org/wiki/Unicode_control_characters
There are dozens of Format Control Characters, for example:
U+00AD SOFT HYPHEN
U+200B ZERO WIDTH SPACE
U+2060 WORD JOINER
"""
import unicodedata
txt2 = filter( lambda c: unicodedata.category(unicode(c)) != 'Cf', txt )
# 2to3 NOTE: The following is needed to work around a broken
# Python3 conversion in which filter() will be transformed
# into a list rather than a string.
if not isinstance(txt2,basestring):
txt2 = u''.join(txt2)
return txt2
@staticmethod
def lookup_codec( encoding ):
"""Wrapper around codecs.lookup().
Returns None if codec not found, rather than raising a LookupError.
"""
import codecs
if isinstance( encoding, codecs.CodecInfo ):
return encoding
encoding = encoding.lower()
import codecs
if helpers.always_use_custom_codecs:
# Try custom utf32 first, then standard python codecs
cdk = utf32.lookup(encoding)
if not cdk:
try:
cdk = codecs.lookup( encoding )
except LookupError:
cdk = None
else:
# Try standard python codecs first, then custom utf32
try:
cdk = codecs.lookup( encoding )
except LookupError:
cdk = utf32.lookup( encoding )
return cdk
@staticmethod
def auto_detect_encoding( s ):
"""Takes a string (or byte array) and tries to determine the Unicode encoding it is in.
Returns the encoding name, as a string.
"""
if not s or len(s)==0:
return "utf-8"
# Get the byte values of up to the first 4 bytes
ords = []
for i in range(0, min(len(s),4)):
x = s[i]
if isinstance(x, basestring):
x = ord(x)
ords.append( x )
# Look for BOM marker
import sys, codecs
bom2, bom3, bom4 = None, None, None
if len(s) >= 2:
bom2 = s[:2]
if len(s) >= 3:
bom3 = s[:3]
if len(s) >= 4:
bom4 = s[:4]
# Assign values of first four bytes to: a, b, c, d; and last byte to: z
a, b, c, d, z = None, None, None, None, None
if len(s) >= 1:
a = ords[0]
if len(s) >= 2:
b = ords[1]
if len(s) >= 3:
c = ords[2]
if len(s) >= 4:
d = ords[3]
z = s[-1]
if isinstance(z, basestring):
z = ord(z)
if bom4 and ( (hasattr(codecs,'BOM_UTF32_LE') and bom4 == codecs.BOM_UTF32_LE) or
(bom4 == utf32.BOM_UTF32_LE) ):
encoding = 'utf-32le'
s = s[4:]
elif bom4 and ( (hasattr(codecs,'BOM_UTF32_BE') and bom4 == codecs.BOM_UTF32_BE) or
(bom4 == utf32.BOM_UTF32_BE) ):
encoding = 'utf-32be'
s = s[4:]
elif bom2 and bom2 == codecs.BOM_UTF16_LE:
encoding = 'utf-16le'
s = s[2:]
elif bom2 and bom2 == codecs.BOM_UTF16_BE:
encoding = 'utf-16be'
s = s[2:]
elif bom3 and bom3 == codecs.BOM_UTF8:
encoding = 'utf-8'
s = s[3:]
# No BOM, so autodetect encoding used by looking at first four
# bytes according to RFC 4627 section 3. The first and last bytes
# in a JSON document will be ASCII. The second byte will be ASCII
# unless the first byte was a quotation mark.
elif len(s)>=4 and a==0 and b==0 and c==0 and d!=0: # UTF-32BE (0 0 0 x)
encoding = 'utf-32be'
elif len(s)>=4 and a!=0 and b==0 and c==0 and d==0 and z==0: # UTF-32LE (x 0 0 0 [... 0])
encoding = 'utf-32le'
elif len(s)>=2 and a==0 and b!=0: # UTF-16BE (0 x)
encoding = 'utf-16be'
elif len(s)>=2 and a!=0 and b==0 and z==0: # UTF-16LE (x 0 [... 0])
encoding = 'utf-16le'
elif ord('\t') <= a <= 127:
# First byte appears to be ASCII, so guess UTF-8.
encoding = 'utf8'
else:
raise ValueError("Can not determine the Unicode encoding for byte stream")
return encoding
@staticmethod
def unicode_decode( txt, encoding=None ):
"""Takes a string (or byte array) and tries to convert it to a Unicode string.
Returns a named tuple: (string, codec, bom)
The 'encoding' argument, if supplied, should either the name of
a character encoding, or an instance of codecs.CodecInfo. If
the encoding argument is None or "auto" then the encoding is
automatically determined, if possible.
Any BOM (Byte Order Mark) that is found at the beginning of the
input will be stripped off and placed in the 'bom' portion of
the returned value.
"""
if isinstance(txt, unicode):
res = _namedtuple('DecodedString',['string','codec','bom'])( txt, None, None )
else:
if encoding is None or encoding == 'auto':
encoding = helpers.auto_detect_encoding( txt )
cdk = helpers.lookup_codec( encoding )
if not cdk:
raise LookupError("Can not find codec for encoding %r" % encoding)
try:
# Determine if codec takes arguments; try a decode of nothing
cdk.decode( helpers.make_raw_bytes([]), errors='strict' )
except TypeError:
cdk_kw = {} # This coded doesn't like the errors argument
else:
cdk_kw = {'errors': 'strict'}
unitxt, numbytes = cdk.decode( txt, **cdk_kw ) # DO THE DECODE HERE!
# Remove BOM if present
if len(unitxt) > 0 and unitxt[0] == u'\uFEFF':
bom = cdk.encode(unitxt[0])[0]
unitxt = unitxt[1:]
elif len(unitxt) > 0 and unitxt[0] == u'\uFFFE': # Reversed BOM
raise UnicodeDecodeError(cdk.name,txt,0,0,"Wrong byte order, found reversed BOM U+FFFE")
else:
bom = None
res = _namedtuple('DecodedString',['string','codec','bom'])( unitxt, cdk, bom )
return res
@staticmethod
def surrogate_pair_as_unicode( c1, c2 ):
"""Takes a pair of unicode surrogates and returns the equivalent unicode character.
The input pair must be a surrogate pair, with c1 in the range
U+D800 to U+DBFF and c2 in the range U+DC00 to U+DFFF.
"""
n1, n2 = ord(c1), ord(c2)
if n1 < 0xD800 or n1 > 0xDBFF or n2 < 0xDC00 or n2 > 0xDFFF:
raise JSONDecodeError('illegal Unicode surrogate pair',(c1,c2))
a = n1 - 0xD800
b = n2 - 0xDC00
v = (a << 10) | b
v += 0x10000
return helpers.safe_unichr(v)
@staticmethod
def unicode_as_surrogate_pair( c ):
"""Takes a single unicode character and returns a sequence of surrogate pairs.
The output of this function is a tuple consisting of one or two unicode
characters, such that if the input character is outside the BMP range
then the output is a two-character surrogate pair representing that character.
If the input character is inside the BMP then the output tuple will have
just a single character...the same one.
"""
n = ord(c)
w1, w2 = helpers.make_surrogate_pair(n)
if w2 is None:
return (unichr(w1),)
else:
return (unichr(w1), unichr(w2))
@staticmethod
def make_surrogate_pair( codepoint ):
"""Given a Unicode codepoint (int) returns a 2-tuple of surrogate codepoints."""
if codepoint < 0x10000:
return (codepoint,None) # in BMP, surrogate pair not required
v = codepoint - 0x10000
vh = (v >> 10) & 0x3ff # highest 10 bits
vl = v & 0x3ff # lowest 10 bits
w1 = 0xD800 | vh
w2 = 0xDC00 | vl
return (w1, w2)
@staticmethod
def isnumbertype( obj ):
"""Is the object of a Python number type (excluding complex)?"""
return isinstance(obj, (int,long,float)) \
and not isinstance(obj, bool) \
or obj is nan or obj is inf or obj is neginf \
or (decimal and isinstance(obj, decimal.Decimal))
@staticmethod
def is_negzero( n ):
"""Is the number value a negative zero?"""
if isinstance( n, float ):
return n == 0.0 and repr(n).startswith('-')
elif decimal and isinstance( n, decimal.Decimal ):
return n.is_zero() and n.is_signed()
else:
return False
@staticmethod
def is_nan( n ):
"""Is the number a NaN (not-a-number)?"""
if isinstance( n, float ):
return n is nan or n.hex() == 'nan' or n != n
elif decimal and isinstance( n, decimal.Decimal ):
return n.is_nan()
else:
return False
@staticmethod
def is_infinite( n ):
"""Is the number infinite?"""
if isinstance( n, float ):
return n is inf or n is neginf or n.hex() in ('inf','-inf')
elif decimal and isinstance( n, decimal.Decimal ):
return n.is_infinite()
else:
return False
@staticmethod
def isstringtype( obj ):
"""Is the object of a Python string type?"""
if isinstance(obj, basestring):
return True
# Must also check for some other pseudo-string types
import types, UserString
return isinstance(obj, types.StringTypes) \
or isinstance(obj, UserString.UserString)
## or isinstance(obj, UserString.MutableString)
@staticmethod
def decode_hex( hexstring ):
"""Decodes a hexadecimal string into it's integer value."""
# We don't use the builtin 'hex' codec in python since it can
# not handle odd numbers of digits, nor raise the same type
# of exceptions we want to.
n = 0
for c in hexstring:
if '0' <= c <= '9':
d = ord(c) - ord('0')
elif 'a' <= c <= 'f':
d = ord(c) - ord('a') + 10
elif 'A' <= c <= 'F':
d = ord(c) - ord('A') + 10
else:
raise ValueError('Not a hexadecimal number', hexstring)
# Could use ((n << 4 ) | d), but python 2.3 issues a FutureWarning.
n = (n * 16) + d
return n
@staticmethod
def decode_octal( octalstring ):
"""Decodes an octal string into it's integer value."""
n = 0
for c in octalstring:
if '0' <= c <= '7':
d = ord(c) - ord('0')
else:
raise ValueError('Not an octal number', octalstring)
# Could use ((n << 3 ) | d), but python 2.3 issues a FutureWarning.
n = (n * 8) + d
return n
@staticmethod
def decode_binary( binarystring ):
"""Decodes a binary string into it's integer value."""
n = 0
for c in binarystring:
if c == '0':
d = 0
elif c == '1':
d = 1
else:
raise ValueError('Not an binary number', binarystring)
# Could use ((n << 3 ) | d), but python 2.3 issues a FutureWarning.
n = (n * 2) + d
return n
@staticmethod
def format_timedelta_iso( td ):
"""Encodes a datetime.timedelta into ISO-8601 Time Period format.
"""
d = td.days
s = td.seconds
ms = td.microseconds
m, s = divmod(s,60)
h, m = divmod(m,60)
a = ['P']
if d:
a.append( '%dD' % d )
if h or m or s or ms:
a.append( 'T' )
if h:
a.append( '%dH' % h )
if m:
a.append( '%dM' % m )
if s or ms:
if ms:
a.append( '%d.%06d' % (s,ms) )
else:
a.append( '%d' % s )
if len(a)==1:
a.append('T0S')
return ''.join(a)
# ----------------------------------------------------------------------
# File position indicator
# ----------------------------------------------------------------------
class position_marker(object):
"""A position marks a specific place in a text document.
It consists of the following attributes:
* line - The line number, starting at 1
* column - The column on the line, starting at 0
* char_position - The number of characters from the start of
the document, starting at 0
* text_after - (optional) a short excerpt of the text of
document starting at the current position
Lines are separated by any Unicode line separator character. As an
exception a CR+LF character pair is treated as being a single line
separator demarcation.
Columns are simply a measure of the number of characters after the
start of a new line, starting at 0. Visual effects caused by
Unicode characters such as combining characters, bidirectional
text, zero-width characters and so on do not affect the
computation of the column regardless of visual appearance.
The char_position is a count of the number of characters since the
beginning of the document, starting at 0. As used within the
buffered_stream class, if the document starts with a Unicode Byte
Order Mark (BOM), the BOM prefix is NOT INCLUDED in the count.
"""
def __init__(self, offset=0, line=1, column=0, text_after=None):
self.__char_position = offset
self.__line = line
self.__column = column
self.__text_after = text_after
self.__at_end = False
self.__last_was_cr = False
@property
def line(self):
"""The current line within the document, starts at 1."""
return self.__line
@property
def column(self):
"""The current character column from the beginning of the
document, starts at 0.
"""
return self.__column
@property
def char_position(self):
"""The current character offset from the beginning of the
document, starts at 0.
"""
return self.__char_position
@property
def at_start(self):
"""Returns True if the position is at the start of the document."""
return (self.char_position == 0)
@property
def at_end(self):
"""Returns True if the position is at the end of the document.
This property must be set by the user.
"""
return self.__at_end
@at_end.setter
def at_end(self, b):
"""Sets the at_end property to True or False.
"""
self.__at_end = bool(b)
@property
def text_after(self):
"""Returns a textual excerpt starting at the current position.
This property must be set by the user.
"""
return self.__at_end
@text_after.setter
def text_after(self, value):
"""Sets the text_after property to a given string.
"""
self.__text_after = value
def __repr__(self):
s = "%s(offset=%r,line=%r,column=%r" \
% (self.__class__.__name__,
self.__char_position,
self.__line,
self.__column)
if self.text_after:
s += ",text_after=%r" % (self.text_after,)
s += ")"
return s
def describe(self, show_text=True):
"""Returns a human-readable description of the position, in English."""
s = "line %d, column %d, offset %d" % (self.__line,
self.__column,
self.__char_position)
if self.at_start:
s += " (AT-START)"
elif self.at_end:
s += " (AT-END)"
if show_text and self.text_after:
s += ", text %r" % (self.text_after)
return s
def __str__(self):
"""Same as the describe() function."""
return self.describe( show_text=True )
def copy( self ):
"""Create a copy of the position object."""
p = self.__class__()
p.__char_position = self.__char_position
p.__line = self.__line
p.__column = self.__column
p.text_after = self.__text_after
p.at_end = self.at_end
p.__last_was_cr = self.__last_was_cr
return p
def rewind( self ):
"""Set the position to the start of the document."""
if not self.at_start:
self.text_after = None
self.at_end = False
self.__char_position = 0
self.__line = 1
self.__column = 0
self.__last_was_cr = False
def advance( self, s ):
"""Advance the position from its current place according to
the given string of characters.
"""
if s:
self.text_after = None
for c in s:
self.__char_position += 1
if c == '\n' and self.__last_was_cr:
self.__last_was_cr = False
elif helpers.char_is_unicode_eol(c):
self.__line += 1
self.__column = 0
self.__last_was_cr = (c == '\r')
else:
self.__column += 1
self.__last_was_cr = False
# ----------------------------------------------------------------------
# Buffered Stream Reader
# ----------------------------------------------------------------------
class buffered_stream(object):
"""A helper class for the JSON parser.
It allows for reading an input document, while handling some
low-level Unicode issues as well as tracking the current position
in terms of line and column position.
"""
def __init__(self, txt='', encoding=None):
self.reset()
self.set_text( txt, encoding )
def reset(self):
"""Clears the state to nothing."""
self.__pos = position_marker()
self.__saved_pos = [] # Stack of saved positions
self.__bom = helpers.make_raw_bytes([]) # contains copy of byte-order mark, if any
self.__codec = None # The CodecInfo
self.__encoding = None # The name of the codec's encoding
self.__input_is_bytes = False
self.__rawbuf = None
self.__raw_bytes = None
self.__cmax = 0
self.num_ws_skipped = 0
def save_position(self):
self.__saved_pos.append( self.__pos.copy() )
return True
def clear_saved_position(self):
if self.__saved_pos:
self.__saved_pos.pop()
return True
else:
return False
def restore_position(self):
try:
old_pos = self.__saved_pos.pop() # Can raise IndexError
except IndexError, err:
raise IndexError("Attempt to restore buffer position that was never saved")
else:
self.__pos = old_pos
return True
def _find_codec(self, encoding):
if encoding is None:
self.__codec = None
self.__encoding = None
elif isinstance(encoding, codecs.CodecInfo):
self.__codec = encoding
self.__encoding = self.__codec.name
else:
self.__encoding = encoding
self.__codec = helpers.lookup_codec( encoding )
if not self.__codec:
raise JSONDecodeError('no codec available for character encoding',encoding)
return self.__codec
def set_text( self, txt, encoding=None ):
"""Changes the input text document and rewinds the position to
the start of the new document.
"""
import sys
self.rewind()
self.__codec = None
self.__bom = None
self.__rawbuf = u''
self.__cmax = 0 # max number of chars in input
try:
decoded = helpers.unicode_decode( txt, encoding )
except JSONError:
raise
except Exception, err:
# Re-raise as a JSONDecodeError
e2 = sys.exc_info()
newerr = JSONDecodeError("a Unicode decoding error occurred")
# Simulate Python 3's: "raise X from Y" exception chaining
newerr.__cause__ = err
newerr.__traceback__ = e2[2]
raise newerr
else:
self.__codec = decoded.codec
self.__bom = decoded.bom
self.__rawbuf = decoded.string
self.__cmax = len(self.__rawbuf)
def __repr__(self):
return '<%s at %r text %r>' % (self.__class__.__name__, self.__pos, self.text_context)
def rewind(self):
"""Resets the position back to the start of the input text."""
self.__pos.rewind()
@property
def codec(self):
"""The codec object used to perform Unicode decoding, or None."""
return self.__codec
@property
def bom(self):
"""The Unicode Byte-Order Mark (BOM), if any, that was present
at the start of the input text. The returned BOM is a string
of the raw bytes, and is not Unicode-decoded.
"""
return self.__bom
@property
def cpos(self):
"""The current character offset from the start of the document."""
return self.__pos.char_position
@property
def position(self):
"""The current position (as a position_marker object).
Returns a copy.
"""
p = self.__pos.copy()
p.text_after = self.text_context
p.at_end = self.at_end
return p
@property
def at_start(self):
"""Returns True if the position is currently at the start of
the document, or False otherwise.
"""
return self.__pos.at_start
@property
def at_end(self):
"""Returns True if the position is currently at the end of the
document, of False otherwise.
"""
c = self.peek()
return (not c)
def at_ws(self, allow_unicode_whitespace=True):
"""Returns True if the current position contains a white-space
character.
"""
c = self.peek()
if not c:
return False
elif allow_unicode_whitespace:
return helpers.char_is_unicode_ws(c)
else:
return helpers.char_is_json_ws(c)
def at_eol(self, allow_unicode_eol=True):
"""Returns True if the current position contains an
end-of-line control character.
"""
c = self.peek()
if not c:
return True # End of file is treated as end of line
elif allow_unicode_eol:
return helpers.char_is_unicode_eol(c)
else:
return helpers.char_is_json_eol(c)
def peek( self, offset=0 ):
"""Returns the character at the current position, or at a
given offset away from the current position. If the position
is beyond the limits of the document size, then an empty
string '' is returned.
"""
i = self.cpos + offset
if i < 0 or i >= self.__cmax:
return ''
return self.__rawbuf[i]
def peekstr( self, span=1, offset=0 ):
"""Returns one or more characters starting at the current
position, or at a given offset away from the current position,
and continuing for the given span length. If the offset and
span go outside the limit of the current document size, then
the returned string may be shorter than the requested span
length.
"""
i = self.cpos + offset
j = i + span
if i < 0 or i >= self.__cmax:
return ''
return self.__rawbuf[i : j]
@property
def text_context( self, context_size = 20 ):
"""A short human-readable textual excerpt of the document at
the current position, in English.
"""
context_size = max( context_size, 4 )
s = self.peekstr(context_size + 1)
if not s:
return ''
if len(s) > context_size:
s = s[:context_size - 3] + "..."
return s
def startswith( self, s ):
"""Determines if the text at the current position starts with
the given string.
See also method: pop_if_startswith()
"""
s2 = self.peekstr( len(s) )
return s == s2
def skip( self, span=1 ):
"""Advances the current position by one (or the given number)
of characters. Will not advance beyond the end of the
document. Returns the number of characters skipped.
"""
i = self.cpos
self.__pos.advance( self.peekstr(span) )
return self.cpos - i
def skipuntil( self, testfn ):
"""Advances the current position until a given predicate test
function succeeds, or the end of the document is reached.
Returns the actual number of characters skipped.
The provided test function should take a single unicode
character and return a boolean value, such as:
lambda c : c == '.' # Skip to next period
See also methods: skipwhile() and popuntil()
"""
i = self.cpos
while True:
c = self.peek()
if not c or testfn(c):
break
else:
self.__pos.advance(c)
return self.cpos - i
def skipwhile( self, testfn ):
"""Advances the current position until a given predicate test
function fails, or the end of the document is reached.
Returns the actual number of characters skipped.
The provided test function should take a single unicode
character and return a boolean value, such as:
lambda c : c.isdigit() # Skip all digits
See also methods: skipuntil() and popwhile()
"""
return self.skipuntil( lambda c: not testfn(c) )
def skip_to_next_line( self, allow_unicode_eol=True ):
"""Advances the current position to the start of the next
line. Will not advance beyond the end of the file. Note that
the two-character sequence CR+LF is recognized as being just a
single end-of-line marker.
"""
ln = self.__pos.line
while True:
c = self.pop()
if not c or self.__pos.line > ln:
if c == '\r' and self.peek() == '\n':
self.skip()
break
def skipws( self, allow_unicode_whitespace=True ):
"""Advances the current position past all whitespace, or until
the end of the document is reached.
"""
if allow_unicode_whitespace:
n = self.skipwhile( helpers.char_is_unicode_ws )
else:
n = self.skipwhile( helpers.char_is_json_ws )
self.num_ws_skipped += n
return n
def pop( self ):
"""Returns the character at the current position and advances
the position to the next character. At the end of the
document this function returns an empty string.
"""
c = self.peek()
if c:
self.__pos.advance( c )
return c
def popstr( self, span=1, offset=0 ):
"""Returns a string of one or more characters starting at the
current position, and advances the position to the following
character after the span. Will not go beyond the end of the
document, so the returned string may be shorter than the
requested span.
"""
s = self.peekstr(span)
if s:
self.__pos.advance( s )
return s
def popif( self, testfn ):
"""Just like the pop() function, but only returns the
character if the given predicate test function succeeds.
"""
c = self.peek()
if c and testfn(c):
self.__pos.advance( c )
return c
return ''
def pop_while_in( self, chars ):
"""Pops a sequence of characters at the current position
as long as each of them is in the given set of characters.
"""
if not isinstance( chars, (set,frozenset)):
cset = set( chars )
c = self.peek()
if c and c in cset:
s = self.popwhile( lambda c: c and c in cset )
return s
return None
def pop_identifier( self, match=None ):
"""Pops the sequence of characters at the current position
that match the syntax for a JavaScript identifier.
"""
c = self.peek()
if c and helpers.char_is_identifier_leader(c):
s = self.popwhile( helpers.char_is_identifier_tail )
return s
return None
def pop_if_startswith( self, s ):
"""Pops the sequence of characters if they match the given string.
See also method: startswith()
"""
s2 = self.peekstr( len(s) )
if s2 != s:
return NULL
self.__pos.advance( s2 )
return s2
def popwhile( self, testfn, maxchars=None ):
"""Pops all the characters starting at the current position as
long as each character passes the given predicate function
test. If maxchars a numeric value instead of None then then
no more than that number of characters will be popped
regardless of the predicate test.
See also methods: skipwhile() and popuntil()
"""
s = []
i = 0
while maxchars is None or i < maxchars:
c = self.popif( testfn )
if not c:
break
s.append( c )
i += 1
return ''.join(s)
def popuntil( self, testfn, maxchars=None ):
"""Just like popwhile() method except the predicate function
should return True to stop the sequence rather than False.
See also methods: skipuntil() and popwhile()
"""
return popwhile( lambda c: not testfn(c), maxchars=maxchars )
def __getitem__( self, index ):
"""Returns the character at the given index relative to the current position.
If the index goes beyond the end of the input, or prior to the
start when negative, then '' is returned.
If the index provided is a slice object, then that range of
characters is returned as a string. Note that a stride value other
than 1 is not supported in the slice. To use a slice, do:
s = my_stream[ 1:4 ]
"""
if isinstance( index, slice ):
return self.peekstr( index.stop - index.start, index.start )
else:
return self.peek( index )
# ----------------------------------------------------------------------
# Exception classes.
# ----------------------------------------------------------------------
class JSONException(Exception):
"""Base class for all JSON-related exceptions.
"""
pass
class JSONSkipHook(JSONException):
"""An exception to be raised by user-defined code within hook
callbacks to indicate the callback does not want to handle the
situation.
"""
pass
class JSONStopProcessing(JSONException):
"""Can be raised by anyplace, including inside a hook function, to
cause the entire encode or decode process to immediately stop
with an error.
"""
pass
class JSONAbort(JSONException):
pass
class JSONError(JSONException):
"""Base class for all JSON-related errors.
In addition to standard Python exceptions, these exceptions may
also have additional properties:
* severity - One of: 'fatal', 'error', 'warning', 'info'
* position - An indication of the position in the input where the error occured.
* outer_position - A secondary position (optional) that gives
the location of the outer data item in which the error
occured, such as the beginning of a string or an array.
* context_description - A string that identifies the context
in which the error occured. Default is "Context".
"""
severities = frozenset(['fatal','error','warning','info'])
def __init__(self, message, *args, **kwargs ):
self.severity = 'error'
self._position = None
self.outer_position = None
self.context_description = None
for kw,val in kwargs.items():
if kw == 'severity':
if val not in self.severities:
raise TypeError("%s given invalid severity %r" % (self.__class__.__name__, val))
self.severity = val
elif kw == 'position':
self.position = val
elif kw == 'outer_position':
self.outer_position = val
elif kw == 'context_description' or kw=='context':
self.context_description = val
else:
raise TypeError("%s does not accept %r keyword argument" % (self.__class__.__name__, kw))
super( JSONError, self ).__init__( message, *args )
self.message = message
@property
def position(self):
return self._position
@position.setter
def position(self, pos):
if pos == 0:
self._position = 0 #position_marker() # start of input
else:
self._position = pos
def __repr__(self):
s = "%s(%r" % (self.__class__.__name__, self.message)
for a in self.args[1:]:
s += ", %r" % (a,)
if self.position:
s += ", position=%r" % (self.position,)
if self.outer_position:
s += ", outer_position=%r" % (self.outer_position,)
s += ", severity=%r)" % (self.severity,)
return s
def pretty_description(self, show_positions=True, filename=None):
if filename:
pfx = filename.rstrip().rstrip(':') + ':'
else:
pfx = ''
# Print file position as numeric abbreviation
err = pfx
if self.position == 0:
err += '0:0:'
elif self.position:
err += '%d:%d:' % (self.position.line, self.position.column)
else:
err += ' '
# Print severity and main error message
err += " %s: %s" % (self.severity.capitalize(), self.message)
if len(self.args) > 1:
err += ': '
for anum, a in enumerate(self.args[1:]):
if anum > 1:
err += ', '
astr = repr(a)
if len(astr) > 30:
astr = astr[:30] + '...'
err += astr
# Print out exception chain
e2 = self
while e2:
if hasattr(e2,'__cause__') and isinstance(e2.__cause__,Exception):
e2 = e2.__cause__
e2desc = str(e2).strip()
if not e2desc:
e2desc = repr(e2).strip()
err += "\n | Cause: %s" % e2desc.strip().replace('\n','\n | ')
else:
e2 = None
# Show file position
if show_positions and self.position is not None:
if self.position == 0:
err += "\n | At start of input"
else:
err += "\n | At %s" % (self.position.describe(show_text=False),)
if self.position.text_after:
err += "\n | near text: %r" % (self.position.text_after,)
# Show context
if show_positions and self.outer_position:
if self.context_description:
cdesc = self.context_description.capitalize()
else:
cdesc = "Context"
err += "\n | %s started at %s" % (cdesc, self.outer_position.describe(show_text=False),)
if self.outer_position.text_after:
err += "\n | with text: %r" % (self.outer_position.text_after,)
return err
class JSONDecodeError(JSONError):
"""An exception class raised when a JSON decoding error (syntax error) occurs."""
pass
class JSONDecodeHookError(JSONDecodeError):
"""An exception that occured within a decoder hook.
The original exception is available in the 'hook_exception' attribute.
"""
def __init__(self, hook_name, exc_info, encoded_obj, *args, **kwargs):
self.hook_name = hook_name
if not exc_info:
exc_info = (None, None, None)
exc_type, self.hook_exception, self.hook_traceback = exc_info
self.object_type = type(encoded_obj)
msg = "Hook %s raised %r while decoding type <%s>" % (hook_name, self.hook_exception.__class__.__name__, self.object_type.__name__)
if len(args) >= 1:
msg += ": " + args[0]
args = args[1:]
super(JSONDecodeHookError,self).__init__(msg, *args,**kwargs)
class JSONEncodeError(JSONError):
"""An exception class raised when a python object can not be encoded as a JSON string."""
pass
class JSONEncodeHookError(JSONEncodeError):
"""An exception that occured within an encoder hook.
The original exception is available in the 'hook_exception' attribute.
"""
def __init__(self, hook_name, exc_info, encoded_obj, *args, **kwargs):
self.hook_name = hook_name
if not exc_info:
exc_info = (None, None, None)
exc_type, self.hook_exception, self.hook_traceback = exc_info
self.object_type = type(encoded_obj)
msg = "Hook %s raised %r while encoding type <%s>" % (self.hook_name, self.hook_exception.__class__.__name__, self.object_type.__name__)
if len(args) >= 1:
msg += ": " + args[0]
args = args[1:]
super(JSONEncodeHookError,self).__init__(msg, *args, **kwargs)
#----------------------------------------------------------------------
# Encoder state object
#----------------------------------------------------------------------
class encode_state(object):
"""An internal transient object used during JSON encoding to
record the current construction state.
"""
def __init__(self, jsopts=None, parent=None ):
import sys
self.chunks = []
if not parent:
self.parent = None
self.nest_level = 0
self.options = jsopts
self.escape_unicode_test = False # or a function f(unichar)=>True/False
else:
self.parent = parent
self.nest_level = parent.nest_level + 1
self.escape_unicode_test = parent.escape_unicode_test
self.options = parent.options
def make_substate(self):
return encode_state( parent=self )
def join_substate(self, other_state):
self.chunks.extend( other_state.chunks )
other_state.chunks = []
def append(self, s):
"""Adds a string to the end of the current JSON document"""
self.chunks.append(s)
def combine(self):
"""Returns the accumulated string and resets the state to empty"""
s = ''.join( self.chunks )
self.chunks = []
return s
def __eq__(self, other_state):
return self.nest_level == other_state.nest_level and \
self.chunks == other_state.chunks
def __lt__(self, other_state):
if self.nest_level != other_state.nest_level:
return self.nest_level < other_state.nest_level
return self.chunks < other_state.chunks
#----------------------------------------------------------------------
# Decoder statistics
#----------------------------------------------------------------------
class decode_statistics(object):
"""An object that records various statistics about a decoded JSON document.
"""
int8_max = 0x7f
int8_min = - 0x7f - 1
int16_max = 0x7fff
int16_min = - 0x7fff - 1
int32_max = 0x7fffffff
int32_min = - 0x7fffffff - 1
int64_max = 0x7fffffffffffffff
int64_min = - 0x7fffffffffffffff - 1
double_int_max = 2**53 - 1
double_int_min = - (2**53 - 1)
def __init__(self):
# Nesting
self.max_depth = 0
self.max_items_in_array = 0
self.max_items_in_object = 0
# Integer stats
self.num_ints = 0
self.num_ints_8bit = 0
self.num_ints_16bit = 0
self.num_ints_32bit = 0
self.num_ints_53bit = 0 # ints which will overflow IEEE doubles
self.num_ints_64bit = 0
self.num_ints_long = 0
self.num_negative_zero_ints = 0
# Floating-point stats
self.num_negative_zero_floats = 0
self.num_floats = 0
self.num_floats_decimal = 0 # overflowed 'float'
# String stats
self.num_strings = 0
self.max_string_length = 0
self.total_string_length = 0
self.min_codepoint = None
self.max_codepoint = None
# Other data type stats
self.num_arrays = 0
self.num_objects = 0
self.num_bools = 0
self.num_nulls = 0
self.num_undefineds = 0
self.num_nans = 0
self.num_infinities = 0
self.num_comments = 0
self.num_identifiers = 0 # JavaScript identifiers
self.num_excess_whitespace = 0
@property
def num_infinites(self):
"""Misspelled 'num_infinities' for backwards compatibility"""
return self.num_infinities
def pretty_description(self, prefix=''):
import unicodedata
lines = [
"Number of integers:",
" 8-bit: %5d (%d to %d)" % (self.num_ints_8bit, self.int8_min, self.int8_max),
" 16-bit: %5d (%d to %d)" % (self.num_ints_16bit, self.int16_min, self.int16_max),
" 32-bit: %5d (%d to %d)" % (self.num_ints_32bit, self.int32_min, self.int32_max),
" > 53-bit: %5d (%d to %d - overflows JavaScript)" % (self.num_ints_53bit, self.double_int_min, self.double_int_max),
" 64-bit: %5d (%d to %d)" % (self.num_ints_64bit, self.int64_min, self.int64_max),
" > 64 bit: %5d (not portable, may require a \"Big Num\" package)" % self.num_ints_long,
" total ints: %5d" % self.num_ints,
" Num -0: %5d (negative-zero integers are not portable)" % self.num_negative_zero_ints,
"Number of floats:",
" doubles: %5d" % self.num_floats,
" > doubles: %5d (will overflow IEEE doubles)" % self.num_floats_decimal,
" total flts: %5d" % (self.num_floats + self.num_floats_decimal),
" Num -0.0: %5d (negative-zero floats are usually portable)" % self.num_negative_zero_floats,
"Number of:",
" nulls: %5d" % self.num_nulls,
" booleans: %5d" % self.num_bools,
" arrays: %5d" % self.num_arrays,
" objects: %5d" % self.num_objects,
"Strings:",
" number: %5d strings" % self.num_strings,
" max length: %5d characters" % self.max_string_length,
" total chars: %5d across all strings" % self.total_string_length,
]
if self.min_codepoint is not None:
cp = 'U+%04X' % self.min_codepoint
try:
charname = unicodedata.name(unichr(self.min_codepoint))
except ValueError:
charname = '? UNKNOWN CHARACTER'
lines.append(" min codepoint: %6s (%s)" % (cp, charname))
else:
lines.append(" min codepoint: %6s" % ('n/a',))
if self.max_codepoint is not None:
cp = 'U+%04X' % self.max_codepoint
try:
charname = unicodedata.name(unichr(self.max_codepoint))
except ValueError:
charname = '? UNKNOWN CHARACTER'
lines.append(" max codepoint: %6s (%s)" % (cp, charname))
else:
lines.append(" max codepoint: %6s" % ('n/a',))
lines.extend([
"Other JavaScript items:",
" NaN: %5d" % self.num_nans,
" Infinite: %5d" % self.num_infinities,
" undefined: %5d" % self.num_undefineds,
" Comments: %5d" % self.num_comments,
" Identifiers: %5d" % self.num_identifiers,
"Max items in any array: %5d" % self.max_items_in_array,
"Max keys in any object: %5d" % self.max_items_in_object,
"Max nesting depth: %5d" % self.max_depth,
])
if self.total_chars == 0:
lines.append("Unnecessary whitespace: 0 of 0 characters")
else:
lines.append(
"Unnecessary whitespace: %5d of %d characters (%.2f%%)" \
% (self.num_excess_whitespace, self.total_chars,
self.num_excess_whitespace * 100.0 / self.total_chars) )
if prefix:
return '\n'.join([ prefix+s for s in lines ]) + '\n'
else:
return '\n'.join( lines ) + '\n'
#----------------------------------------------------------------------
# Decoder state object
#----------------------------------------------------------------------
class decode_state(object):
"""An internal transient object used during JSON decoding to
record the current parsing state and error messages.
"""
def __init__(self, options=None):
self.reset()
self.options = options
def reset(self):
"""Clears all errors, statistics, and input text."""
self.buf = None
self.errors = []
self.obj = None
self.cur_depth = 0 # how deep in nested structures are we?
self.stats = decode_statistics()
self._have_warned_nonbmp = False
self._have_warned_long_string = False
self._have_warned_max_depth = False
@property
def should_stop(self):
if self.has_fatal:
return True
return False
@property
def has_errors(self):
"""Have any errors been seen already?"""
return len([err for err in self.errors if err.severity in ('fatal','error')]) > 0
@property
def has_fatal(self):
"""Have any errors been seen already?"""
return len([err for err in self.errors if err.severity in ('fatal',)]) > 0
def set_input( self, txt, encoding=None ):
"""Initialize the state by setting the input document text."""
import sys
self.reset()
try:
self.buf = buffered_stream( txt, encoding=encoding )
except JSONError as err:
err.position = 0 # set position to start of file
err.severity = 'fatal'
self.push_exception( err )
except Exception as err:
# Re-raise as JSONDecodeError
e2 = sys.exc_info()
newerr = JSONDecodeError("Error while reading input", position=0, severity='fatal')
self.push_exception( err )
self.buf = None
else:
if self.buf.bom:
self.push_cond( self.options.bom,
"JSON document was prefixed by a BOM (Byte Order Mark)",
self.buf.bom )
if not self.buf:
self.push_fatal( "Aborting, can not read JSON document.", position=0 )
def push_exception(self, exc):
"""Add an already-built exception to the error list."""
self.errors.append(exc)
def push_fatal(self, message, *args, **kwargs):
"""Create a fatal error."""
kwargs['severity'] = 'fatal'
self.__push_err( message, *args, **kwargs)
def push_error(self, message, *args, **kwargs):
"""Create an error."""
kwargs['severity'] = 'error'
self.__push_err( message, *args, **kwargs)
def push_warning(self, message, *args, **kwargs):
"""Create a warning."""
kwargs['severity'] = 'warning'
self.__push_err( message, *args, **kwargs)
def push_info(self, message, *args, **kwargs):
"""Create a informational message."""
kwargs['severity'] = 'info'
self.__push_err( message, *args, **kwargs)
def push_cond(self, behavior_value, message, *args, **kwargs):
"""Creates an conditional error or warning message.
The behavior value (from json_options) controls whether
a message will be pushed and whether it is an error
or warning message.
"""
if behavior_value == ALLOW:
return
elif behavior_value == WARN:
kwargs['severity'] = 'warning'
else:
kwargs['severity'] = 'error'
self.__push_err( message, *args, **kwargs )
def __push_err(self, message, *args, **kwargs):
"""Stores an error in the error list."""
position = None
outer_position = None
severity = 'error'
context_description = None
for kw, val in kwargs.items():
if kw == 'position': position = val
elif kw == 'outer_position': outer_position = val
elif kw == 'severity': severity = val
elif kw == 'context_description' or kw == 'context':
context_description=val
else:
raise TypeError('Unknown keyword argument',kw)
if position is None and self.buf:
position = self.buf.position # Current position
err = JSONDecodeError( message, position=position, outer_position=outer_position, context_description=context_description, severity=severity, *args)
self.push_exception( err )
def update_depth_stats(self, **kwargs):
st = self.stats
st.max_depth = max(st.max_depth, self.cur_depth)
if not self._have_warned_max_depth and self.cur_depth > self.options.warn_max_depth:
self._have_warned_max_depth = True
self.push_cond( self.options.non_portable,
"Arrays or objects nested deeper than %d levels may not be portable" \
% self.options.warn_max_depth )
def update_string_stats(self, s, **kwargs):
st = self.stats
st.num_strings += 1
st.max_string_length = max(st.max_string_length, len(s))
st.total_string_length += len(s)
if self.options.warn_string_length and len(s) > self.options.warn_string_length and not self._have_warned_long_string:
self._have_warned_long_string = True
self.push_cond( self.options.non_portable,
"Strings longer than %d may not be portable" % self.options.warn_string_length,
**kwargs )
if len(s) > 0:
mincp = ord(min(s))
maxcp = ord(max(s))
if st.min_codepoint is None:
st.min_codepoint = mincp
st.max_codepoint = maxcp
else:
st.min_codepoint = min( st.min_codepoint, mincp )
st.max_codepoint = max( st.max_codepoint, maxcp )
if maxcp > 0xffff and not self._have_warned_nonbmp:
self._have_warned_nonbmp = True
self.push_cond( self.options.non_portable,
"Strings containing non-BMP characters (U+%04X) may not be portable" % maxcp,
**kwargs )
def update_negzero_int_stats(self, **kwargs):
st = self.stats
st.num_negative_zero_ints += 1
if st.num_negative_zero_ints == 1: # Only warn once
self.push_cond( self.options.non_portable,
"Negative zero (-0) integers are usually not portable",
**kwargs )
def update_negzero_float_stats(self, **kwargs):
st = self.stats
st.num_negative_zero_floats += 1
if st.num_negative_zero_floats == 1: # Only warn once
self.push_cond( self.options.non_portable,
"Negative zero (-0.0) numbers may not be portable",
**kwargs)
def update_float_stats(self, float_value, **kwargs):
st = self.stats
if 'sign' in kwargs:
del kwargs['sign']
if helpers.is_negzero( float_value ):
self.update_negzero_float_stats( **kwargs )
if helpers.is_infinite( float_value ):
st.num_infinities += 1
if isinstance(float_value, decimal.Decimal):
st.num_floats_decimal += 1
if st.num_floats_decimal == 1: # Only warn once
self.push_cond( self.options.non_portable,
"Floats larger or more precise than an IEEE \"double\" may not be portable",
**kwargs)
elif isinstance(float_value, float):
st.num_floats += 1
def update_integer_stats(self, int_value, **kwargs ):
sign=kwargs.get('sign', 1)
if 'sign' in kwargs:
del kwargs['sign']
if int_value == 0 and sign < 0:
self.update_negzero_int_stats( **kwargs )
if sign < 0:
int_value = - int_value
st = self.stats
st.num_ints += 1
if st.int8_min <= int_value <= st.int8_max:
st.num_ints_8bit += 1
elif st.int16_min <= int_value <= st.int16_max:
st.num_ints_16bit += 1
elif st.int32_min <= int_value <= st.int32_max:
st.num_ints_32bit += 1
elif st.int64_min <= int_value <= st.int64_max:
st.num_ints_64bit += 1
else:
st.num_ints_long += 1
if int_value < st.double_int_min or st.double_int_max < int_value:
st.num_ints_53bit += 1
if st.num_ints_53bit == 1: # Only warn once
self.push_cond( self.options.non_portable,
"Integers larger than 53-bits are not portable",
**kwargs )
# ----------------------------------------------------------------------
# JSON strictness options
# ----------------------------------------------------------------------
STRICTNESS_STRICT = 'strict'
STRICTNESS_WARN = 'warn'
STRICTNESS_TOLERANT = 'tolerant'
ALLOW = 'allow'
WARN = 'warn'
FORBID = 'forbid'
# For float_type option
NUMBER_AUTO = 'auto'
NUMBER_FLOAT = 'float'
NUMBER_DECIMAL = 'decimal'
# For json_int class
NUMBER_FORMAT_DECIMAL = 'decimal'
NUMBER_FORMAT_HEX = 'hex'
NUMBER_FORMAT_LEGACYOCTAL = 'legacyoctal'
NUMBER_FORMAT_OCTAL = 'octal'
NUMBER_FORMAT_BINARY = 'binary'
class _behaviors_metaclass(type):
"""Meta class used to establish a set of "behavior" options.
Classes that use this meta class must defined a class-level
variable called '_behaviors' that is a list of tuples, each of
which describes one behavior and is like: (behavior_name,
documentation). Also define a second class-level variable called
'_behavior_values' which is a list of the permitted values for
each behavior, each being strings.
For each behavior (e.g., pretty), and for each value (e.g.,
yes) the following methods/properties will be created:
* pretty - value of 'pretty' behavior (read-write)
* ispretty_yes - returns True if 'pretty' is 'yes'
For each value (e.g., pink) the following methods/properties
will be created:
* all_behaviors - set of all behaviors (read-only)
* pink_behaviors - set of behaviors with value of 'pink' (read-only)
* set_all('pink')
* set_all_pink() - set all behaviors to value of 'pink'
"""
def __new__(cls, clsname, bases, attrs):
values = attrs.get('_behavior_values')
attrs['values'] = property( lambda self: set(self._behavior_values), doc='Set of possible behavior values')
behaviors = attrs.get('_behaviors')
def get_behavior(self, name):
"""Returns the value for a given behavior"""
try:
return getattr( self, '_behavior_'+name )
except AttributeError:
raise ValueError('Unknown behavior',name)
attrs['get_behavior'] = get_behavior
def set_behavior(self, name, value):
"""Changes the value for a given behavior"""
if value not in self._behavior_values:
raise ValueError('Unknown value for behavior',value)
varname = '_behavior_'+name
if hasattr(self,varname):
setattr( self, varname, value )
else:
raise ValueError('Unknown behavior',name)
attrs['set_behavior'] = set_behavior
def describe_behavior(self,name):
"""Returns documentation about a given behavior."""
for n, doc in self._behaviors:
if n==name:
return doc
else:
raise AttributeError('No such behavior',name)
attrs['describe_behavior'] = describe_behavior
for name, doc in behaviors:
attrs['_behavior_'+name] = True
for v in values:
vs = v + '_' + name
def getx(self,name=name,forval=v):
return self.get_behavior(name) == forval
attrs['is_'+v+'_'+name] = property(getx,doc=v.capitalize()+' '+doc)
# method value_name()
fnset = lambda self,_name=name,_value=v: self.set_behavior(_name,_value)
fnset.__name__ = v+'_'+name
fnset.__doc__ = 'Set behavior ' + name + ' to ' + v + "."
attrs[fnset.__name__] = fnset
def get_value_for_behavior(self,name=name):
return self.get_behavior(name)
def set_value_for_behavior(self,value,name=name):
self.set_behavior(name,value)
attrs[name] = property(get_value_for_behavior,set_value_for_behavior,doc=doc)
@property
def all_behaviors(self):
"""Returns the names of all known behaviors."""
return set([t[0] for t in self._behaviors])
attrs['all_behaviors'] = all_behaviors
def set_all(self,value):
"""Changes all behaviors to have the given value."""
if value not in self._behavior_values:
raise ValueError('Unknown behavior',value)
for name in self.all_behaviors:
setattr(self, '_behavior_'+name, value)
attrs['set_all'] = set_all
def is_all(self,value):
"""Determines if all the behaviors have the given value."""
if value not in self._behavior_values:
raise ValueError('Unknown behavior',value)
for name in self.all_behaviors:
if getattr(self, '_behavior_'+name) != value:
return False
return True
attrs['is_all'] = is_all
for v in values:
# property value_behaviors
def getbehaviorsfor(self,value=v):
return set([name for name in self.all_behaviors if getattr(self,name)==value])
attrs[v+'_behaviors'] = property(getbehaviorsfor,doc='Return the set of behaviors with the value '+v+'.')
# method set_all_value()
setfn = lambda self,_value=v: set_all(self,_value)
setfn.__name__ = 'set_all_'+v
setfn.__doc__ = 'Set all behaviors to value ' + v + "."
attrs[setfn.__name__] = setfn
# property is_all_value
attrs['is_all_'+v] = property( lambda self,v=v: is_all(self,v), doc='Determines if all the behaviors have the value '+v+'.')
def behaviors_eq(self, other):
"""Determines if two options objects are equivalent."""
if self.all_behaviors != other.all_behaviors:
return False
return self.allowed_behaviors == other.allowed_behaviors
attrs['__eq__'] = behaviors_eq
return super(_behaviors_metaclass, cls).__new__(cls, clsname, bases, attrs)
SORT_NONE = 'none'
SORT_PRESERVE = 'preserve'
SORT_ALPHA = 'alpha'
SORT_ALPHA_CI = 'alpha_ci'
SORT_SMART = 'smart'
sorting_methods = {
SORT_NONE: "Do not sort, resulting order may be random",
SORT_PRESERVE: "Preserve original order when reformatting",
SORT_ALPHA: "Sort strictly alphabetically",
SORT_ALPHA_CI: "Sort alphabetically case-insensitive",
SORT_SMART: "Sort alphabetically and numerically (DEFAULT)"
}
sorting_method_aliases = {
'ci': SORT_ALPHA_CI
}
def smart_sort_transform( key ):
numfmt = '%012d'
digits = '0123456789'
zero = ord('0')
if not key:
key = ''
elif isinstance( key, (int,long) ):
key = numfmt % key
elif isinstance( key, basestring ):
keylen = len(key)
words = []
i=0
while i < keylen:
if key[i] in digits:
num = 0
while i < keylen and key[i] in digits:
num *= 10
num += ord(key[i]) - zero
i += 1
words.append( numfmt % num )
else:
words.append( key[i].upper() )
i += 1
key = ''.join(words)
else:
key = str(key)
return key
# Find Enum type (introduced in Python 3.4)
try:
from enum import Enum as _enum
except ImportError:
_enum = None
# Find OrderedDict type
try:
from collections import OrderedDict as _OrderedDict
except ImportError:
_OrderedDict = None
class json_options(object):
"""Options to determine how strict the decoder or encoder should be."""
__metaclass__ = _behaviors_metaclass
_behavior_values = (ALLOW, WARN, FORBID)
_behaviors = (
("all_numeric_signs",
"Numbers may be prefixed by any \'+\' and \'-\', e.g., +4, -+-+77"),
("any_type_at_start",
"A JSON document may start with any type, not just arrays or objects"),
("comments",
"JavaScript comments, both /*...*/ and //... styles"),
("control_char_in_string",
"Strings may contain raw control characters without \\u-escaping"),
("hex_numbers",
"Hexadecimal numbers, e.g., 0x1f"),
("binary_numbers",
"Binary numbers, e.g., 0b1001"),
("octal_numbers",
"New-style octal numbers, e.g., 0o731 (see leading-zeros for legacy octals)"),
("initial_decimal_point",
"Floating-point numbers may start with a decimal point (no units digit)"),
("extended_unicode_escapes",
"Extended Unicode escape sequence \\u{..} for non-BMP characters"),
("js_string_escapes",
"All JavaScript character \\-escape sequences may be in strings"),
("leading_zeros",
"Numbers may have extra leading zeros (see --leading-zero-radix option)"),
("non_numbers",
"Non-numbers may be used, such as NaN or Infinity"),
("nonescape_characters",
"Unknown character \\-escape sequences stand for that character (\\Q -> 'Q')"),
("identifier_keys",
"JavaScript identifiers are converted to strings when used as object keys"),
("nonstring_keys",
"Value types other than strings (or identifiers) may be used as object keys"),
("omitted_array_elements",
"Arrays may have omitted/elided elements, e.g., [1,,3] == [1,undefined,3]"),
("single_quoted_strings",
"Strings may be delimited with both double (\") and single (\') quotation marks"),
("trailing_comma",
"A final comma may end the list of array or object members"),
("trailing_decimal_point",
"Floating-point number may end with a decimal point and no following fractional digits"),
("undefined_values",
"The JavaScript 'undefined' value may be used"),
("format_control_chars",
"Unicode \"format control characters\" may appear in the input"),
("unicode_whitespace",
"Treat any Unicode whitespace character as valid whitespace"),
# Never legal
("leading_zeros",
"Numbers may have leading zeros"),
# Normally warnings
("duplicate_keys",
"Objects may have repeated keys"),
("zero_byte",
"Strings may contain U+0000, which may not be safe for C-based programs"),
("bom",
"A JSON document may start with a Unicode BOM (Byte Order Mark)"),
("non_portable",
"Anything technically valid but likely to cause data portablibity issues"),
) # end behavior list
def reset_to_defaults(self):
# Plain attrs (other than above behaviors) are simply copied
# by value, either during initialization (via keyword
# arguments) or via the copy() method.
self._plain_attrs = ['leading_zero_radix',
'encode_namedtuple_as_object',
'encode_enum_as',
'encode_compactly',
'escape_unicode',
'always_escape_chars',
'warn_string_length',
'warn_max_depth',
'int_as_float',
'decimal_context',
'float_type',
'keep_format',
'date_format',
'datetime_format',
'time_format',
'timedelta_format',
'sort_keys',
'indent_amount', 'indent_tab_width', 'indent_limit',
'max_items_per_line',
'py2str_encoding' ]
self.strictness = STRICTNESS_WARN
self._leading_zero_radix = 8 # via property: leading_zero_radix
self._sort_keys = SORT_SMART # via property: sort_keys
self.int_as_float = False
self.float_type = NUMBER_AUTO
self.decimal_context = (decimal.DefaultContext if decimal else None)
self.keep_format = False # keep track of when numbers are hex, octal, etc.
self.encode_namedtuple_as_object = True
self._encode_enum_as = 'name' # via property
self.encode_compactly = True
self.escape_unicode = False
self.always_escape_chars = None # None, or a set of Unicode characters to always escape
self.warn_string_length = 0xfffd # with 16-bit length prefix
self.warn_max_depth = 64
self.date_format = 'iso' # or strftime format
self.datetime_format = 'iso' # or strftime format
self.time_format = 'iso' # or strftime format
self.timedelta_format = 'iso' # or 'hms'
self.sort_keys = SORT_ALPHA
self.indent_amount = 2
self.indent_tab_width = 0 # 0, or number of equivalent spaces
self.indent_limit = None
self.max_items_per_line = 1 # When encoding how many items per array/object
# before breaking into multiple lines
# For interpreting Python 2 'str' types:
if _py_major == 2:
self.py2str_encoding = 'ascii'
else:
self.py2str_encoding = None
def __init__(self, **kwargs):
"""Set JSON encoding and decoding options.
If 'strict' is set to True, then only strictly-conforming JSON
output will be produced. Note that this means that some types
of values may not be convertable and will result in a
JSONEncodeError exception.
If 'compactly' is set to True, then the resulting string will
have all extraneous white space removed; if False then the
string will be "pretty printed" with whitespace and indentation
added to make it more readable.
If 'escape_unicode' is set to True, then all non-ASCII characters
will be represented as a unicode escape sequence; if False then
the actual real unicode character will be inserted if possible.
The 'escape_unicode' can also be a function, which when called
with a single argument of a unicode character will return True
if the character should be escaped or False if it should not.
"""
self.reset_to_defaults()
if 'strict' in kwargs:
# Do this keyword first, so other keywords may override specific behaviors
self.strictness = kwargs['strict']
for kw,val in kwargs.items():
if kw == 'compactly': # alias for 'encode_compactly'
self.encode_compactly = val
elif kw == 'strict':
pass # Already handled
elif kw == 'warnings':
if val:
self.suppress_warnings()
elif kw == 'html_safe' or kw == 'xml_safe':
if bool(val):
if self.always_escape_chars is None:
self.always_escape_chars = set(u'<>/&')
else:
self.always_escape_chars.update( set(u'<>/&') )
elif kw == 'always_escape':
if val:
if self.always_escape_chars is None:
self.always_escape_chars = set(val)
else:
self.always_escape_chars.update( set(val) )
elif kw == 'int_as_float':
self.int_as_float = bool(val)
elif kw == 'keep_format':
self.keep_format = bool(val)
elif kw == 'float_type':
if val in (NUMBER_AUTO, NUMBER_FLOAT, NUMBER_DECIMAL):
self.float_type = val
else:
raise ValueError("Unknown option %r for argument %r to initialize %s" % (val,kw,self.__class__.__name__))
elif kw == 'decimal' or kw == 'decimal_context':
if decimal:
if not val or val == 'default':
self.decimal_context = decimal.DefaultContext
elif val == 'basic':
self.decimal_context = decimal.BasicContext
elif val == 'extended':
self.decimal_context = decimal.ExtendedContext
elif isinstance(val, decimal.Context):
self.decimal_context = val
elif isinstance(val,(int,long)) or val[0].isdigit:
prec = int(val)
self.decimal_context = decimal.Context( prec=prec )
else:
raise ValueError("Option for %r should be a decimal.Context, a number of significant digits, or one of 'default','basic', or 'extended'." % (kw,))
elif kw in ('allow','warn','forbid','prevent','deny'):
action = {'allow':ALLOW, 'warn':WARN, 'forbid':FORBID, 'prevent':FORBID, 'deny':FORBID}[ kw ]
if isinstance(val,basestring):
val = [b.replace('-','_') for b in val.replace(',',' ').split()]
for behavior in val:
self.set_behavior( behavior, action )
elif kw.startswith('allow_') or kw.startswith('forbid_') or kw.startswith('prevent_') or kw.startswith('deny_') or kw.startswith('warn_'):
action, behavior = kw.split('_',1)
if action == 'allow':
if val:
self.set_behavior( behavior, ALLOW )
else:
self.set_behavior( behavior, FORBID )
elif action in ('forbid','prevent','deny'):
if val:
self.set_behavior( behavior, FORBID )
else:
self.set_behavior( behavior, ALLOW )
elif action == 'warn':
if val:
self.set_behavior( behavior, WARN )
else:
self.set_behavior( behavior, ALLOW )
elif kw in self._plain_attrs:
setattr(self, kw, val)
else:
raise ValueError("Unknown keyword argument %r to initialize %s" % (kw,self.__class__.__name__))
def copy(self):
other = self.__class__()
other.copy_from( self )
return other
def copy_from(self, other):
if self is other:
return # Myself!
self.strictness = other.strictness # sets behaviors in bulk
for name in self.all_behaviors:
self.set_behavior( name, other.get_behavior(name) )
for name in self._plain_attrs:
val = getattr(other,name)
if isinstance(val, set):
val = val.copy()
elif decimal and isinstance(val, decimal.Decimal):
val = val.copy()
setattr(self, name, val)
def spaces_to_next_indent_level( self, min_spaces=1, subtract=0 ):
n = self.indent_amount - subtract
if n < 0:
n = 0
n = max( min_spaces, n )
return ' ' * n
def indentation_for_level( self, level=0 ):
"""Returns a whitespace string used for indenting."""
if self.indent_limit is not None and level > self.indent_limit:
n = self.indent_limit
else:
n = level
n *= self.indent_amount
if self.indent_tab_width:
tw, sw = divmod(n, self.indent_tab_width)
return '\t'*tw + ' '*sw
else:
return ' ' * n
def set_indent( self, num_spaces, tab_width=0, limit=None ):
"""Changes the indentation properties when outputting JSON in non-compact mode.
'num_spaces' is the number of spaces to insert for each level
of indentation, which defaults to 2.
'tab_width', if not 0, is the number of spaces which is equivalent
to one tab character. Tabs will be output where possible rather
than runs of spaces.
'limit', if not None, is the maximum indentation level after
which no further indentation will be output.
"""
n = int(num_spaces)
if n < 0:
raise ValueError("indentation amount can not be negative",n)
self.indent_amount = n
self.indent_tab_width = tab_width
self.indent_limit = limit
@property
def sort_keys(self):
"""The method used to sort dictionary keys when encoding JSON
"""
return self._sort_keys
@sort_keys.setter
def sort_keys(self, method):
if not method:
self._sort_keys = SORT_NONE
elif callable(method):
self._sort_keys = method
elif method in sorting_methods:
self._sort_keys = method
elif method in sorting_method_aliases: # alias
self._sort_keys = sorting_method_aliases[method]
elif method == True:
self._sort_keys = SORT_ALPHA
else:
raise ValueError("Not a valid sorting method: %r" % method)
@property
def encode_enum_as(self):
"""The strategy for encoding Python Enum values.
"""
return self._encode_enum_as
@encode_enum_as.setter
def encode_enum_as(self, val):
if val not in ('name','qname','value'):
raise ValueError("encode_enum_as must be one of 'name','qname', or 'value'")
self._encode_enum_as = val
@property
def zero_float(self):
"""The numeric value 0.0, either a float or a decimal."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.decimal_context.create_decimal('0.0')
else:
return 0.0
@property
def negzero_float(self):
"""The numeric value -0.0, either a float or a decimal."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.decimal_context.create_decimal('-0.0')
else:
return -0.0
@property
def nan(self):
"""The numeric value NaN, either a float or a decimal."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.decimal_context.create_decimal('NaN')
else:
return nan
@property
def inf(self):
"""The numeric value Infinity, either a float or a decimal."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.decimal_context.create_decimal('Infinity')
else:
return inf
@property
def neginf(self):
"""The numeric value -Infinity, either a float or a decimal."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.decimal_context.create_decimal('-Infinity')
else:
return neginf
def make_int( self, s, sign=None, number_format=NUMBER_FORMAT_DECIMAL ):
"""Makes an integer value according to the current options.
First argument should be a string representation of the number,
or an integer.
Returns a number value, which could be an int, float, or decimal.
"""
if isinstance(sign, (int,long)):
if sign < 0:
sign = '-'
else:
sign = '+'
if isinstance(s,basestring):
if s.startswith('-') or s.startswith('+'):
sign = s[0]
s = s[1:]
if self.int_as_float:
# Making a float/decimal
if isinstance(s, (int,long)):
if self.float_type == NUMBER_DECIMAL:
n = self.decimal_context.create_decimal( s )
if sign=='-':
n = n.copy_negate()
elif s == 0 and sign=='-':
n = self.negzero_float
elif -999999999999999 <= s <= 999999999999999:
n = float(s)
if sign=='-':
n *= -1
else:
n = float(s)
if (n == inf or int(n) != s) and self.float_type != NUMBER_FLOAT:
n = self.decimal_context.create_decimal( s )
if sign=='-':
n = n.copy_negate()
elif sign=='-':
n *= -1
else: # not already an int
n = self.make_float( s, sign )
n2 = self.make_float( s[:-1] + ('9' if s[-1]<='5' else '0'), sign )
if (n==inf or n==n2) and self.float_type != NUMBER_FLOAT:
n = self.make_decimal( s, sign )
elif isinstance( s, (int,long) ):
# already an integer
n = s
if sign=='-':
if n == 0:
n = self.negzero_float
else:
n *= -1
else:
# Making an actual integer
try:
n = int( s )
except ValueError:
n = self.nan
else:
if sign=='-':
if n==0:
n = self.negzero_float
else:
n *= -1
if isinstance(n,(int,long)) and self.keep_format:
n = json_int(n, number_format=number_format)
return n
def make_decimal( self, s, sign='+' ):
"""Converts a string into a decimal or float value."""
if not decimal or self.float_type == NUMBER_FLOAT:
return self.make_float( s, sign )
if s.startswith('-') or s.startswith('+'):
sign = s[0]
s = s[1:]
elif isinstance(sign, (int,long)):
if sign < 0:
sign = '-'
else:
sign = '+'
try:
f = self.decimal_context.create_decimal( s )
except decimal.InvalidOperation:
f = self.decimal_context.create_decimal( 'NaN' )
except decimal.Overflow:
if sign=='-':
f = self.decimal_context.create_decimal( '-Infinity' )
else:
f = self.decimal_context.create_decimal( 'Infinity' )
else:
if sign=='-':
f = f.copy_negate()
return f
def make_float( self, s, sign='+' ):
"""Converts a string into a float or decimal value."""
if decimal and self.float_type == NUMBER_DECIMAL:
return self.make_decimal( s, sign )
if s.startswith('-') or s.startswith('+'):
sign = s[0]
s = s[1:]
elif isinstance(sign, (int,long)):
if sign < 0:
sign = '-'
else:
sign = '+'
try:
f = float(s)
except ValueError:
f = nan
else:
if sign=='-':
f *= -1
return f
@property
def leading_zero_radix(self):
"""The radix to be used for numbers with leading zeros. 8 or 10
"""
return self._leading_zero_radix
@leading_zero_radix.setter
def leading_zero_radix(self, radix):
if isinstance(radix,basestring):
try:
radix = int(radix)
except ValueError:
radix = radix.lower()
if radix=='octal' or radix=='oct' or radix=='8':
radix = 8
elif radix=='decimal' or radix=='dec':
radix = 10
if radix not in (8,10):
raise ValueError("Radix must either be 8 (octal) or 10 (decimal)")
self._leading_zero_radix = radix
@property
def leading_zero_radix_as_word(self):
return {8:'octal', 10:'decimal'}[ self._leading_zero_radix ]
def suppress_warnings(self):
for name in self.warn_behaviors:
self.set_behavior(name, 'allow')
@property
def allow_or_warn_behaviors(self):
"""Returns the set of all behaviors that are not forbidden (i.e., are allowed or warned)."""
return self.allow_behaviors.union( self.warn_behaviors )
@property
def strictness(self):
return self._strictness
@strictness.setter
def strictness(self, strict):
"""Changes whether the options should be re-configured for strict JSON conformance."""
if strict == STRICTNESS_WARN:
self._strictness = STRICTNESS_WARN
self.set_all_warn()
elif strict == STRICTNESS_STRICT or strict is True:
self._strictness = STRICTNESS_STRICT
self.keep_format = False
self.set_all_forbid()
self.warn_duplicate_keys()
self.warn_zero_byte()
self.warn_bom()
self.warn_non_portable()
elif strict == STRICTNESS_TOLERANT or strict is False:
self._strictness = STRICTNESS_TOLERANT
self.set_all_allow()
self.warn_duplicate_keys()
self.warn_zero_byte()
self.warn_leading_zeros()
self.leading_zero_radix = 8
self.warn_bom()
self.allow_non_portable()
else:
raise ValueError("Unknown strictness options %r" % strict)
self.allow_any_type_at_start()
# ----------------------------------------------------------------------
# The main JSON encoder/decoder class.
# ----------------------------------------------------------------------
class JSON(object):
"""An encoder/decoder for JSON data streams.
Usually you will call the encode() or decode() methods. The other
methods are for lower-level processing.
Whether the JSON parser runs in strict mode (which enforces exact
compliance with the JSON spec) or the more forgiving non-string mode
can be affected by setting the 'strict' argument in the object's
initialization; or by assigning True or False to the 'strict'
property of the object.
You can also adjust a finer-grained control over strictness by
allowing or forbidding specific behaviors. You can get a list of
all the available behaviors by accessing the 'behaviors' property.
Likewise the 'allowed_behaviors' and 'forbidden_behaviors' list which
behaviors will be allowed and which will not. Call the allow()
or forbid() methods to adjust these.
"""
_string_quotes = '"\''
_escapes_json = { # character escapes in JSON
'"': '"',
'/': '/',
'\\': '\\',
'b': '\b',
'f': '\f',
'n': '\n',
'r': '\r',
't': '\t',
}
_escapes_js = { # character escapes in Javascript
'"': '"',
'\'': '\'',
'\\': '\\',
'b': '\b',
'f': '\f',
'n': '\n',
'r': '\r',
't': '\t',
'v': '\v',
'0': '\x00'
}
# Following is a reverse mapping of escape characters, used when we
# output JSON. Only those escapes which are always safe (e.g., in JSON)
# are here. It won't hurt if we leave questionable ones out.
_rev_escapes = {'\n': '\\n',
'\t': '\\t',
'\b': '\\b',
'\r': '\\r',
'\f': '\\f',
'"': '\\"',
'\\': '\\\\' }
_optional_rev_escapes = { '/': '\\/' } # only escaped if forced to do so
json_syntax_characters = u"{}[]\"\\,:0123456789.-+abcdefghijklmnopqrstuvwxyz \t\n\r"
all_hook_names = ('decode_number', 'decode_float', 'decode_object',
'decode_array', 'decode_string',
'encode_value', 'encode_dict', 'encode_dict_key',
'encode_sequence', 'encode_bytes', 'encode_default')
def __init__(self, **kwargs):
"""Creates a JSON encoder/decoder object.
You may pass encoding and decoding options either by passing
an argument named 'json_options' with an instance of a
json_options class; or with individual keyword/values that will
be used to initialize a new json_options object.
You can also set hooks by using keyword arguments using the
hook name; e.g., encode_dict=my_hook_func.
"""
import sys, unicodedata, re
kwargs = kwargs.copy()
# Initialize hooks
for hookname in self.all_hook_names:
if hookname in kwargs:
self.set_hook( hookname, kwargs[hookname] )
del kwargs[hookname]
else:
self.set_hook( hookname, None )
# Set options
if 'json_options' in kwargs:
self._options = kwargs['json_options']
else:
self._options = json_options(**kwargs)
# The following is a boolean map of the first 256 characters
# which will quickly tell us which of those characters never
# need to be escaped.
self._asciiencodable = \
[32 <= c < 128 \
and not self._rev_escapes.has_key(chr(c)) \
and not unicodedata.category(unichr(c)) in ['Cc','Cf','Zl','Zp']
for c in range(0,256)]
@property
def options(self):
"""The optional behaviors used, e.g., the JSON conformance
strictness. Returns an instance of json_options.
"""
return self._options
def clear_hook(self, hookname):
"""Unsets a hook callback, as previously set with set_hook()."""
self.set_hook( hookname, None )
def clear_all_hooks(self):
"""Unsets all hook callbacks, as previously set with set_hook()."""
for hookname in self.all_hook_names:
self.clear_hook( hookname )
def set_hook(self, hookname, function):
"""Sets a user-defined callback function used during encoding or decoding.
The 'hookname' argument must be a string containing the name of
one of the available hooks, listed below.
The 'function' argument must either be None, which disables the hook,
or a callable function. Hooks do not stack, if you set a hook it will
undo any previously set hook.
Netsted values. When decoding JSON that has nested objects or
arrays, the decoding hooks will be called once for every
corresponding value, even if nested. Generally the decoding
hooks will be called from the inner-most value outward, and
then left to right.
Skipping. Any hook function may raise a JSONSkipHook exception
if it does not wish to handle the particular invocation. This
will have the effect of skipping the hook for that particular
value, as if the hook was net set.
AVAILABLE HOOKS:
* decode_string
Called for every JSON string literal with the
Python-equivalent string value as an argument. Expects to
get a Python object in return.
* decode_float:
Called for every JSON number that looks like a float (has
a "."). The string representation of the number is passed
as an argument. Expects to get a Python object in return.
* decode_number:
Called for every JSON number. The string representation of
the number is passed as an argument. Expects to get a
Python object in return. NOTE: If the number looks like a
float and the 'decode_float' hook is set, then this hook
will not be called.
* decode_array:
Called for every JSON array. A Python list is passed as
the argument, and expects to get a Python object back.
NOTE: this hook will get called for every array, even
for nested arrays.
* decode_object:
Called for every JSON object. A Python dictionary is passed
as the argument, and expects to get a Python object back.
NOTE: this hook will get called for every object, even
for nested objects.
* encode_value:
Called for every Python object which is to be encoded into JSON.
* encode_dict:
Called for every Python dictionary or anything that looks
like a dictionary.
* encode_dict_key:
Called for every dictionary key.
* encode_sequence:
Called for every Python sequence-like object that is not a
dictionary or string. This includes lists and tuples.
* encode_bytes:
Called for every Python bytes or bytearray type; or for
any memoryview with a byte ('B') item type. (Python 3 only)
* encode_default:
Called for any Python type which can not otherwise be converted
into JSON, even after applying any other encoding hooks.
"""
if hookname in self.all_hook_names:
att = hookname + '_hook'
if function != None and not callable(function):
raise ValueError("Hook %r must be None or a callable function" % hookname)
setattr( self, att, function )
else:
raise ValueError("Unknown hook name %r" % hookname)
def has_hook(self, hook_name):
if not hook_name or hook_name not in self.all_hook_names:
return False
hook = getattr( self, hook_name + '_hook' )
return callable(hook)
def call_hook(self, hook_name, input_object, position=None, *args, **kwargs):
"""Wrapper function to invoke a user-supplied hook function.
This will capture any exceptions raised by the hook and do something
appropriate with it.
"""
import sys
if hook_name not in self.all_hook_names:
raise AttributeError("No such hook %r" % hook_name)
hook = getattr( self, hook_name + '_hook' )
if not callable(hook):
raise TypeError("Hook is not callable: %r" % (hook,))
try:
rval = hook( input_object, *args, **kwargs )
except JSONSkipHook:
raise # Do nothing
except Exception, err:
exc_info = sys.exc_info()
if hook_name.startswith('encode_'):
ex_class = JSONEncodeHookError
else:
ex_class = JSONDecodeHookError
if isinstance(err, JSONStopProcessing):
severity = 'fatal'
else:
severity = 'error'
newerr = ex_class( hook_name, exc_info, input_object, *args, position=position, severity=severity )
# Simulate Python 3's: "raise X from Y" exception chaining
newerr.__cause__ = err
newerr.__traceback__ = exc_info[2]
raise newerr
return rval
def isws(self, c):
"""Determines if the given character is considered as white space.
Note that Javscript is much more permissive on what it considers
to be whitespace than does JSON.
Ref. ECMAScript section 7.2
"""
if not self.options.unicode_whitespace:
return c in ' \t\n\r'
else:
if not isinstance(c,unicode):
c = unicode(c)
if c in u' \t\n\r\f\v':
return True
import unicodedata
return unicodedata.category(c) == 'Zs'
def islineterm(self, c):
"""Determines if the given character is considered a line terminator.
Ref. ECMAScript section 7.3
"""
if c == '\r' or c == '\n':
return True
if c == u'\u2028' or c == u'\u2029': # unicodedata.category(c) in ['Zl', 'Zp']
return True
return False
def recover_parser(self, state):
"""Try to recover after a syntax error by locating the next "known" position."""
buf = state.buf
buf.skipuntil( lambda c: c in ",:[]{}\"\';" or helpers.char_is_unicode_eol(c) )
stopchar = buf.peek()
self.skipws(state)
if buf.at_end:
state.push_info("Could not recover parsing after previous error",position=buf.position)
else:
state.push_info("Recovering parsing after character %r" % stopchar, position=buf.position)
return stopchar
def decode_null(self, state):
"""Intermediate-level decoder for ECMAScript 'null' keyword.
Takes a string and a starting index, and returns a Python
None object and the index of the next unparsed character.
"""
buf = state.buf
start_position = buf.position
kw = buf.pop_identifier()
if not kw or kw != 'null':
state.push_error("Expected a 'null' keyword'", kw, position=start_position)
else:
state.stats.num_nulls += 1
return None
def encode_undefined(self, state):
"""Produces the ECMAScript 'undefined' keyword."""
state.append('undefined')
def encode_null(self, state):
"""Produces the JSON 'null' keyword."""
state.append('null')
def decode_boolean(self, state):
"""Intermediate-level decode for JSON boolean literals.
Takes a string and a starting index, and returns a Python bool
(True or False) and the index of the next unparsed character.
"""
buf = state.buf
start_position = buf.position
kw = buf.pop_identifier()
if not kw or kw not in ('true','false'):
state.push_error("Expected a 'true' or 'false' keyword'", kw, position=start_position)
else:
state.stats.num_bools += 1
return (kw == 'true')
def encode_boolean(self, bval, state):
"""Encodes the Python boolean into a JSON Boolean literal."""
state.append( 'true' if bool(bval) else 'false' )
def decode_number(self, state):
"""Intermediate-level decoder for JSON numeric literals.
Takes a string and a starting index, and returns a Python
suitable numeric type and the index of the next unparsed character.
The returned numeric type can be either of a Python int,
long, or float. In addition some special non-numbers may
also be returned such as nan, inf, and neginf (technically
which are Python floats, but have no numeric value.)
Ref. ECMAScript section 8.5.
"""
buf = state.buf
self.skipws(state)
start_position = buf.position
# Use external number parser hook if available
if self.has_hook('decode_number') or self.has_hook('decode_float'):
c = buf.peek()
if c and c in '-+0123456789.': # First chars for a number-like value
buf.save_position()
nbr = buf.pop_while_in( '-+0123456789abcdefABCDEF' 'NaN' 'Infinity.' )
if '.' in nbr and self.has_hook('decode_float'):
hook_name = 'decode_float'
elif self.has_hook('decode_number'):
hook_name = 'decode_number'
else:
hook_name = None
if hook_name:
try:
val = self.call_hook( hook_name, nbr, position=start_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
val = undefined
else:
buf.clear_saved_position()
return val
# Hook didn't handle it, restore old position
buf.restore_position()
# Detect initial sign character(s)
sign = +1
sign_count = 0
sign_saw_plus = False
sign_saw_ws = False
c = buf.peek()
while c and c in '+-':
if c == '-':
sign = sign * -1
elif c == '+':
sign_saw_plus = True
sign_count += 1
buf.skip()
if self.skipws_nocomments(state) > 0:
sign_saw_ws = True
c = buf.peek()
if sign_count > 1 or sign_saw_plus:
state.push_cond( self.options.all_numeric_signs,
'Numbers may only have a single "-" as a sign prefix',
position=start_position)
if sign_saw_ws:
state.push_error('Spaces may not appear between a +/- number sign and the digits', position=start_position)
# Check for ECMAScript symbolic non-numbers
if not c:
state.push_error('Missing numeric value after sign', position=start_position)
self.recover_parser(state)
self.stats.num_undefineds += 1
return undefined
elif c.isalpha() or c in '_$':
kw = buf.popwhile( lambda c: c.isalnum() or c in '_$' )
if kw == 'NaN':
state.push_cond( self.options.non_numbers,
'NaN literals are not allowed in strict JSON',
position=start_position)
state.stats.num_nans += 1
return self.options.nan
elif kw == 'Infinity':
state.push_cond( self.options.non_numbers,
'Infinity literals are not allowed in strict JSON',
position=start_position)
state.stats.num_infinities += 1
if sign < 0:
return self.options.neginf
else:
return self.options.inf
else:
state.push_error('Unknown numeric value keyword', kw, position=start_position)
return undefined
# Check for radix-prefixed numbers
elif c == '0' and (buf.peek(1) in [u'x',u'X']):
# ----- HEX NUMBERS 0x123
prefix = buf.popstr(2)
digits = buf.popwhile( helpers.is_hex_digit )
state.push_cond( self.options.hex_numbers,
'Hexadecimal literals are not allowed in strict JSON', prefix+digits,
position=start_position )
if len(digits)==0:
state.push_error('Hexadecimal number is invalid', position=start_position)
self.recover_parser(state)
return undefined
ival = helpers.decode_hex( digits )
state.update_integer_stats( ival, sign=sign, position=start_position )
n = state.options.make_int( ival, sign, number_format=NUMBER_FORMAT_HEX )
return n
elif c == '0' and (buf.peek(1) in [u'o','O']):
# ----- NEW-STYLE OCTAL NUMBERS 0o123
prefix = buf.popstr(2)
digits = buf.popwhile( helpers.is_octal_digit )
state.push_cond( self.options.octal_numbers,
"Octal literals are not allowed in strict JSON", prefix+digits,
position=start_position )
if len(digits)==0:
state.push_error("Octal number is invalid", position=start_position)
self.recover_parser(state)
return undefined
ival = helpers.decode_octal( digits )
state.update_integer_stats( ival, sign=sign, position=start_position )
n = state.options.make_int( ival, sign, number_format=NUMBER_FORMAT_OCTAL )
return n
elif c == '0' and (buf.peek(1) in [u'b','B']):
# ----- NEW-STYLE BINARY NUMBERS 0b1101
prefix = buf.popstr(2)
digits = buf.popwhile( helpers.is_binary_digit )
state.push_cond( self.options.binary_numbers,
"Binary literals are not allowed in strict JSON", prefix+digits,
position=start_position )
if len(digits)==0:
state.push_error("Binary number is invalid", position=start_position)
self.recover_parser(state)
return undefined
ival = helpers.decode_binary( digits )
state.update_integer_stats( ival, sign=sign, position=start_position )
n = state.options.make_int( ival, sign, number_format=NUMBER_FORMAT_BINARY )
return n
else:
# ----- DECIMAL OR LEGACY-OCTAL NUMBER. 123, 0123
# General syntax is: \d+[\.\d+][e[+-]?\d+]
number = buf.popwhile( lambda c: c in '0123456789.+-eE' )
imax = len(number)
if imax == 0:
state.push_error('Missing numeric value', position=start_position)
has_leading_zero = False
units_digits = [] # digits making up whole number portion
fraction_digits = [] # digits making up fractional portion
exponent_digits = [] # digits making up exponent portion (excluding sign)
esign = '+' # sign of exponent
sigdigits = 0 # number of significant digits (approximate)
saw_decimal_point = False
saw_exponent = False
# Break number into parts in a first pass...use a mini state machine
in_part = 'units'
for i, c in enumerate(number):
if c == '.':
if in_part != 'units':
state.push_error('Bad number', number, position=start_position)
self.recover_parser(state)
return undefined
in_part = 'fraction'
saw_decimal_point = True
elif c in 'eE':
if in_part == 'exponent':
state.push_error('Bad number', number, position=start_position)
self.recover_parser(state)
return undefined
in_part = 'exponent'
saw_exponent = True
elif c in '+-':
if in_part != 'exponent' or exponent_digits:
state.push_error('Bad number', number, position=start_position)
self.recover_parser(state)
return undefined
esign = c
else: #digit
if in_part == 'units':
units_digits.append( c )
elif in_part == 'fraction':
fraction_digits.append( c )
elif in_part == 'exponent':
exponent_digits.append( c )
units_s = ''.join(units_digits)
fraction_s = ''.join(fraction_digits)
exponent_s = ''.join(exponent_digits)
# Basic syntax rules checking
is_integer = not (saw_decimal_point or saw_exponent)
if not units_s and not fraction_s:
state.push_error('Bad number', number, position=start_position)
self.recover_parser(state)
return undefined
if saw_decimal_point and not fraction_s:
state.push_cond( self.options.trailing_decimal_point,
'Bad number, decimal point must be followed by at least one digit',
number, position=start_position)
fraction_s = '0'
if saw_exponent and not exponent_s:
state.push_error('Bad number, exponent is missing', number, position=start_position)
self.recover_parser(state)
return undefined
if not units_s:
state.push_cond( self.options.initial_decimal_point,
'Bad number, decimal point must be preceded by at least one digit',
number, position=start_position)
units = '0'
elif len(units_s) > 1 and units_s[0] == '0':
has_leading_zero = True
if self.options.is_forbid_leading_zeros:
state.push_cond( self.options.leading_zeros,
'Numbers may not have extra leading zeros',
number, position=start_position)
elif self.options.is_warn_leading_zeros:
state.push_cond( self.options.leading_zeros,
'Numbers may not have leading zeros; interpreting as %s' \
% self.options.leading_zero_radix_as_word,
number, position=start_position)
# Estimate number of significant digits
sigdigits = len( (units_s + fraction_s).replace('0',' ').strip() )
# Handle legacy octal integers.
if has_leading_zero and is_integer and self.options.leading_zero_radix == 8:
# ----- LEGACY-OCTAL 0123
try:
ival = helpers.decode_octal( units_s )
except ValueError:
state.push_error('Bad number, not a valid octal value', number, position=start_position)
self.recover_parser(state)
return self.options.nan # undefined
state.update_integer_stats( ival, sign=sign, position=start_position )
n = state.options.make_int( ival, sign, number_format=NUMBER_FORMAT_LEGACYOCTAL )
return n
# Determine the exponential part
if exponent_s:
try:
exponent = int(exponent_s)
except ValueError:
state.push_error('Bad number, bad exponent', number, position=start_position)
self.recover_parser(state)
return undefined
if esign == '-':
exponent = - exponent
else:
exponent = 0
# Try to make an int/long first.
if not saw_decimal_point and exponent >= 0:
# ----- A DECIMAL INTEGER
ival = int(units_s)
if exponent != 0:
ival *= 10**exponent
state.update_integer_stats( ival, sign=sign, position=start_position )
n = state.options.make_int( ival, sign )
else:
# ----- A FLOATING-POINT NUMBER
try:
if exponent < float_minexp or exponent > float_maxexp or sigdigits > float_sigdigits:
n = state.options.make_decimal( number, sign )
else:
n = state.options.make_float( number, sign )
except ValueError as err:
state.push_error('Bad number, %s' % err.message, number, position=start_position)
n = undefined
else:
state.update_float_stats( n, sign=sign, position=start_position )
return n
def encode_number(self, n, state):
"""Encodes a Python numeric type into a JSON numeric literal.
The special non-numeric values of float('nan'), float('inf')
and float('-inf') are translated into appropriate JSON
literals.
Note that Python complex types are not handled, as there is no
ECMAScript equivalent type.
"""
if isinstance(n, complex):
if n.imag:
raise JSONEncodeError('Can not encode a complex number that has a non-zero imaginary part',n)
n = n.real
if isinstance(n, json_int):
state.append( n.json_format() )
return
if isinstance(n, (int,long)):
state.append( str(n) )
return
if decimal and isinstance(n, decimal.Decimal):
if n.is_nan(): # Could be 'NaN' or 'sNaN'
state.append( 'NaN' )
elif n.is_infinite():
if n.is_signed():
state.append( '-Infinity' )
else:
state.append( 'Infinity' )
else:
s = str(n).lower()
if 'e' not in s and '.' not in s:
s = s + '.0'
state.append( s )
return
global nan, inf, neginf
if n is nan:
state.append( 'NaN' )
elif n is inf:
state.append( 'Infinity' )
elif n is neginf:
state.append( '-Infinity' )
elif isinstance(n, float):
# Check for non-numbers.
# In python nan == inf == -inf, so must use repr() to distinguish
reprn = repr(n).lower()
if ('inf' in reprn and '-' in reprn) or n == neginf:
state.append( '-Infinity' )
elif 'inf' in reprn or n is inf:
state.append( 'Infinity' )
elif 'nan' in reprn or n is nan:
state.append( 'NaN' )
else:
# A normal float.
state.append( repr(n) )
else:
raise TypeError('encode_number expected an integral, float, or decimal number type',type(n))
def decode_string(self, state):
"""Intermediate-level decoder for JSON string literals.
Takes a string and a starting index, and returns a Python
string (or unicode string) and the index of the next unparsed
character.
"""
buf = state.buf
self.skipws(state)
quote = buf.peek()
if quote == '"':
pass
elif quote == "'":
state.push_cond( self.options.single_quoted_strings,
'String literals must use double quotation marks in strict JSON' )
else:
state.push_error('String literal must be properly quoted')
return undefined
string_position = buf.position
buf.skip()
if self.options.is_forbid_js_string_escapes:
escapes = self._escapes_json
else:
escapes = self._escapes_js
ccallowed = not self.options.is_forbid_control_char_in_string
chunks = []
_append = chunks.append
# Used to track the last seen high-surrogate character
high_surrogate = None
highsur_position = None
# Used to track if errors occured so we don't keep reporting multiples
had_lineterm_error = False
# Start looping character by character until the final quotation mark
saw_final_quote = False
should_stop = False
while not saw_final_quote and not should_stop:
if buf.at_end:
state.push_error("String literal is not terminated",
outer_position=string_position, context='String')
break
c = buf.peek()
# Make sure a high surrogate is immediately followed by a low surrogate
if high_surrogate:
if 0xdc00 <= ord(c) <= 0xdfff:
low_surrogate = buf.pop()
try:
uc = helpers.surrogate_pair_as_unicode( high_surrogate, low_surrogate )
except ValueError as err:
state.push_error( 'Illegal Unicode surrogate pair', (high_surrogate, low_surrogate),
position=highsur_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
uc = u'\ufffd' # replacement char
_append( uc )
high_surrogate = None
highsur_position = None
continue # ==== NEXT CHAR
elif buf.peekstr(2) != '\\u':
state.push_error('High unicode surrogate must be followed by a low surrogate',
position=highsur_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
_append( u'\ufffd' ) # replacement char
high_surrogate = None
highsur_position = None
if c == quote:
buf.skip() # skip over closing quote
saw_final_quote = True
break
elif c == '\\':
# Escaped character
escape_position = buf.position
buf.skip() # skip over backslash
c = buf.peek()
if not c:
state.push_error('Escape in string literal is incomplete', position=escape_position,
outer_position=string_position, context='String')
should_stop = state.should_stop
break
elif helpers.is_octal_digit(c):
# Handle octal escape codes first so special \0 doesn't kick in yet.
# Follow Annex B.1.2 of ECMAScript standard.
if '0' <= c <= '3':
maxdigits = 3
else:
maxdigits = 2
digits = buf.popwhile( helpers.is_octal_digit, maxchars=maxdigits )
n = helpers.decode_octal(digits)
if n == 0:
state.push_cond( self.options.zero_byte,
'Zero-byte character (U+0000) in string may not be universally safe',
"\\"+digits, position=escape_position, outer_position=string_position,
context='String')
else: # n != 0
state.push_cond( self.options.octal_numbers,
"JSON does not allow octal character escapes other than \"\\0\"",
"\\"+digits, position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
if n < 128:
_append( chr(n) )
else:
_append( helpers.safe_unichr(n) )
elif escapes.has_key(c):
buf.skip()
_append( escapes[c] )
elif c == 'u' or c == 'x':
buf.skip()
esc_opener = '\\' + c
esc_closer = ''
if c == 'u':
if buf.peek() == '{':
buf.skip()
esc_opener += '{'
esc_closer = '}'
maxdigits = None
state.push_cond( self.options.extended_unicode_escapes,
"JSON strings do not allow \\u{...} escapes",
position=escape_position, outer_position=string_position,
context='String')
else:
maxdigits = 4
else: # c== 'x'
state.push_cond( self.options.js_string_escapes,
"JSON strings may not use the \\x hex-escape",
position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
maxdigits = 2
digits = buf.popwhile( helpers.is_hex_digit, maxchars=maxdigits )
if esc_closer:
if buf.peek() != esc_closer:
state.push_error( "Unicode escape sequence is missing closing \'%s\'" % esc_closer, esc_opener+digits,
position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
else:
buf.skip()
esc_sequence = esc_opener + digits + esc_closer
if not digits:
state.push_error('numeric character escape sequence is truncated', esc_sequence,
position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
codepoint = 0xfffd # replacement char
else:
if maxdigits and len(digits) != maxdigits:
state.push_error('escape sequence has too few hexadecimal digits', esc_sequence,
position=escape_position, outer_position=string_position,
context='String')
codepoint = helpers.decode_hex( digits )
if codepoint > 0x10FFFF:
state.push_error( 'Unicode codepoint is beyond U+10FFFF', esc_opener+digits+esc_closer,
position=escape_position, outer_position=string_position,
context='String')
codepoint = 0xfffd # replacement char
if high_surrogate:
# Decode surrogate pair and clear high surrogate
low_surrogate = unichr(codepoint)
try:
uc = helpers.surrogate_pair_as_unicode( high_surrogate, low_surrogate )
except ValueError as err:
state.push_error( 'Illegal Unicode surrogate pair', (high_surrogate, low_surrogate), position=highsur_position,
outer_position=string_position,
context='String')
should_stop = state.should_stop
uc = u'\ufffd' # replacement char
_append( uc )
high_surrogate = None
highsur_position = None
elif codepoint < 128:
# ASCII chars always go in as a str
if codepoint==0:
state.push_cond( self.options.zero_byte,
'Zero-byte character (U+0000) in string may not be universally safe',
position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
_append( chr(codepoint) )
elif 0xd800 <= codepoint <= 0xdbff: # high surrogate
high_surrogate = unichr(codepoint) # remember until we get to the low surrogate
highsur_position = escape_position.copy()
elif 0xdc00 <= codepoint <= 0xdfff: # low surrogate
state.push_error('Low unicode surrogate must be proceeded by a high surrogate', position=escape_position,
outer_position=string_position,
context='String')
should_stop = state.should_stop
_append( u'\ufffd' ) # replacement char
else:
# Other chars go in as a unicode char
_append( helpers.safe_unichr(codepoint) )
else:
# Unknown escape sequence
state.push_cond( self.options.nonescape_characters,
'String escape code is not allowed in strict JSON',
'\\'+c, position=escape_position, outer_position=string_position,
context='String')
should_stop = state.should_stop
_append( c )
buf.skip()
elif ord(c) <= 0x1f: # A control character
if ord(c) == 0:
state.push_cond( self.options.zero_byte,
'Zero-byte character (U+0000) in string may not be universally safe',
position=buf.position, outer_position=string_position,
context='String')
should_stop = state.should_stop
if self.islineterm(c):
if not had_lineterm_error:
state.push_error('Line terminator characters must be escaped inside string literals',
'U+%04X'%ord(c),
position=buf.position, outer_position=string_position,
context='String')
should_stop = state.should_stop
had_lineterm_error = True
_append( c )
buf.skip()
elif ccallowed:
_append( c )
buf.skip()
else:
state.push_error('Control characters must be escaped inside JSON string literals',
'U+%04X'%ord(c),
position=buf.position, outer_position=string_position,
context='String')
should_stop = state.should_stop
buf.skip()
elif 0xd800 <= ord(c) <= 0xdbff: # a raw high surrogate
high_surrogate = buf.pop() # remember until we get to the low surrogate
highsur_position = buf.position.copy()
else: # A normal character; not an escape sequence or end-quote.
# Find a whole sequence of "safe" characters so we can append them
# all at once rather than one a time, for speed.
chunk = buf.popwhile( lambda c: c not in helpers.unsafe_string_chars and c != quote )
if not chunk:
_append( c )
buf.skip()
else:
_append( chunk )
# Check proper string termination
if high_surrogate:
state.push_error('High unicode surrogate must be followed by a low surrogate',
position=highsur_position, outer_position=string_position,
context='String')
_append( u'\ufffd' ) # replacement char
high_surrogate = None
highsur_position = None
if not saw_final_quote:
state.push_error('String literal is not terminated with a quotation mark', position=buf.position,
outer_position=string_position,
context='String')
if state.should_stop:
return undefined
# Compose the python string and update stats
s = ''.join( chunks )
state.update_string_stats( s, position=string_position )
# Call string hook
if self.has_hook('decode_string'):
try:
s = self.call_hook( 'decode_string', s, position=string_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
s = undefined
return s
def encode_string(self, s, state):
"""Encodes a Python string into a JSON string literal.
"""
# Must handle instances of UserString specially in order to be
# able to use ord() on it's simulated "characters". Also
# convert Python2 'str' types to unicode strings first.
import unicodedata, sys
import UserString
py2strenc = self.options.py2str_encoding
if isinstance(s, UserString.UserString):
def tochar(c):
c2 = c.data
if py2strenc and not isinstance(c2,unicode):
return c2.decode( py2strenc )
else:
return c2
elif py2strenc and not isinstance(s,unicode):
s = s.decode( py2strenc )
tochar = None
else:
# Could use "lambda c:c", but that is too slow. So we set to None
# and use an explicit if test inside the loop.
tochar = None
chunks = []
chunks.append('"')
revesc = self._rev_escapes
optrevesc = self._optional_rev_escapes
asciiencodable = self._asciiencodable
always_escape = state.options.always_escape_chars
encunicode = state.escape_unicode_test
i = 0
imax = len(s)
while i < imax:
if tochar:
c = tochar(s[i])
else:
c = s[i]
cord = ord(c)
if cord < 256 and asciiencodable[cord] and isinstance(encunicode, bool) \
and not (always_escape and c in always_escape):
# Contiguous runs of plain old printable ASCII can be copied
# directly to the JSON output without worry (unless the user
# has supplied a custom is-encodable function).
j = i
i += 1
while i < imax:
if tochar:
c = tochar(s[i])
else:
c = s[i]
cord = ord(c)
if cord < 256 and asciiencodable[cord] \
and not (always_escape and c in always_escape):
i += 1
else:
break
chunks.append( unicode(s[j:i]) )
elif revesc.has_key(c):
# Has a shortcut escape sequence, like "\n"
chunks.append(revesc[c])
i += 1
elif cord <= 0x1F:
# Always unicode escape ASCII-control characters
chunks.append(r'\u%04x' % cord)
i += 1
elif 0xD800 <= cord <= 0xDFFF:
# A raw surrogate character!
# This should ONLY happen in "narrow" Python builds
# where (sys.maxunicode == 65535) as Python itself
# uses UTF-16. But for "wide" Python builds, a raw
# surrogate should never happen.
handled_raw_surrogates = False
if sys.maxunicode == 0xFFFF and 0xD800 <= cord <= 0xDBFF and (i+1) < imax:
# In a NARROW Python, output surrogate pair as-is
hsurrogate = cord
i += 1
if tochar:
c = tochar(s[i])
else:
c = s[i]
cord = ord(c)
i += 1
if 0xDC00 <= cord <= 0xDFFF:
lsurrogate = cord
chunks.append(r'\u%04x\u%04x' % (hsurrogate,lsurrogate))
handled_raw_surrogates = True
if not handled_raw_surrogates:
cname = 'U+%04X' % cord
raise JSONEncodeError('can not include or escape a Unicode surrogate character',cname)
elif cord <= 0xFFFF:
# Other BMP Unicode character
if always_escape and c in always_escape:
doesc = True
elif unicodedata.category( c ) in ['Cc','Cf','Zl','Zp']:
doesc = True
elif callable(encunicode):
doesc = encunicode( c )
else:
doesc = encunicode
if doesc:
if optrevesc.has_key(c):
chunks.append(optrevesc[c])
else:
chunks.append(r'\u%04x' % cord)
else:
chunks.append( c )
i += 1
else: # ord(c) >= 0x10000
# Non-BMP Unicode
if always_escape and c in always_escape:
doesc = True
elif unicodedata.category( c ) in ['Cc','Cf','Zl','Zp']:
doesc = True
elif callable(encunicode):
doesc = encunicode( c )
else:
doesc = encunicode
if doesc:
for surrogate in helpers.unicode_as_surrogate_pair(c):
chunks.append(r'\u%04x' % ord(surrogate))
else:
chunks.append( c )
i += 1
chunks.append('"')
state.append( ''.join( chunks ) )
def decode_identifier(self, state, identifier_as_string=False):
"""Decodes an identifier/keyword.
"""
buf = state.buf
self.skipws(state)
start_position = buf.position
obj = None
kw = buf.pop_identifier()
if not kw:
state.push_error("Expected an identifier", position=start_position)
elif kw == 'null':
obj = None
state.stats.num_nulls += 1
elif kw == 'true':
obj = True
state.stats.num_bools += 1
elif kw == 'false':
obj = False
state.stats.num_bools += 1
elif kw == 'undefined':
state.push_cond( self.options.undefined_values,
"Strict JSON does not allow the 'undefined' keyword",
kw, position=start_position)
obj = undefined
state.stats.num_undefineds += 1
elif kw == 'NaN' or kw == 'Infinity':
state.push_cond( self.options.non_numbers,
"%s literals are not allowed in strict JSON" % kw,
kw, position=start_position)
if self.has_hook('decode_float'):
try:
val = self.call_hook( 'decode_float', kw, position=start_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
return undefined
else:
return val
elif self.has_hook('decode_number'):
try:
val = self.call_hook( 'decode_number', kw, position=start_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
return undefined
else:
return val
if kw == 'NaN':
state.stats.num_nans += 1
obj = state.options.nan
else:
state.stats.num_infinities += 1
obj = state.options.inf
else:
# Convert unknown identifiers into strings
if identifier_as_string:
if kw in helpers.javascript_reserved_words:
state.push_warning( "Identifier is a JavaScript reserved word",
kw, position=start_position)
state.push_cond( self.options.identifier_keys,
"JSON does not allow identifiers to be used as strings",
kw, position=start_position)
state.stats.num_identifiers += 1
obj = self.decode_javascript_identifier( kw )
else:
state.push_error("Unknown identifier", kw, position=start_position)
obj = undefined
state.stats.num_identifiers += 1
return obj
def skip_comment(self, state):
"""Skips an ECMAScript comment, either // or /* style.
The contents of the comment are returned as a string, as well
as the index of the character immediately after the comment.
"""
buf = state.buf
uniws = self.options.unicode_whitespace
s = buf.peekstr(2)
if s != '//' and s != '/*':
return None
state.push_cond( self.options.comments, 'Comments are not allowed in strict JSON' )
start_position = buf.position
buf.skip(2)
multiline = (s == '/*')
saw_close = False
while not buf.at_end:
if multiline:
if buf.peekstr(2) == '*/':
buf.skip(2)
saw_close = True
break
elif buf.peekstr(2) == '/*':
state.push_error('Multiline /* */ comments may not nest',
outer_position=start_position,
context='Comment')
else:
if buf.at_eol( uniws ):
buf.skip_to_next_line( uniws )
saw_close = True
break
buf.pop()
if not saw_close and multiline:
state.push_error('Comment was never terminated', outer_position=start_position,
context='Comment')
state.stats.num_comments += 1
def skipws_nocomments(self, state):
"""Skips whitespace (will not allow comments).
"""
return state.buf.skipws( not self.options.is_forbid_unicode_whitespace )
def skipws(self, state):
"""Skips all whitespace, including comments and unicode whitespace
Takes a string and a starting index, and returns the index of the
next non-whitespace character.
If the 'skip_comments' behavior is True and not running in
strict JSON mode, then comments will be skipped over just like
whitespace.
"""
buf = state.buf
uniws = not self.options.unicode_whitespace
while not buf.at_end:
c = buf.peekstr(2)
if c == '/*' or c == '//':
cmt = self.skip_comment( state )
elif buf.at_ws( uniws ):
buf.skipws( uniws )
else:
break
def decode_composite(self, state):
"""Intermediate-level JSON decoder for composite literal types (array and object).
"""
if state.should_stop:
return None
buf = state.buf
self.skipws(state)
opener = buf.peek()
if opener not in '{[':
state.push_error('Composite data must start with "[" or "{"')
return None
start_position = buf.position
buf.skip()
if opener == '[':
isdict = False
closer = ']'
obj = []
else:
isdict = True
closer = '}'
if state.options.sort_keys == SORT_PRESERVE and _OrderedDict:
obj = _OrderedDict()
else:
obj = {}
num_items = 0
self.skipws(state)
c = buf.peek()
if c == closer:
# empty composite
buf.skip()
done = True
else:
saw_value = False # set to false at beginning and after commas
done = False
while not done and not buf.at_end and not state.should_stop:
self.skipws(state)
c = buf.peek()
if c == '':
break # will report error futher down because done==False
elif c == ',':
if not saw_value:
# no preceeding value, an elided (omitted) element
if isdict:
state.push_error('Can not omit elements of an object (dictionary)',
outer_position=start_position,
context='Object')
else:
state.push_cond( self.options.omitted_array_elements,
'Can not omit elements of an array (list)',
outer_position=start_position,
context='Array')
obj.append( undefined )
if state.stats:
state.stats.num_undefineds += 1
buf.skip() # skip over comma
saw_value = False
continue
elif c == closer:
if not saw_value:
if isdict:
state.push_cond( self.options.trailing_comma,
'Strict JSON does not allow a final comma in an object (dictionary) literal',
outer_position=start_position,
context='Object')
else:
state.push_cond( self.options.trailing_comma,
'Strict JSON does not allow a final comma in an array (list) literal',
outer_position=start_position,
context='Array')
buf.skip() # skip over closer
done = True
break
elif c in ']}':
if isdict:
cdesc='Object'
else:
cdesc='Array'
state.push_error("Expected a '%c' but saw '%c'" % (closer,c),
outer_position=start_position, context=cdesc)
done = True
break
if state.should_stop:
break
# Decode the item/value
value_position = buf.position
if isdict:
val = self.decodeobj(state, identifier_as_string=True)
else:
val = self.decodeobj(state, identifier_as_string=False)
if val is syntax_error:
recover_c = self.recover_parser(state)
if recover_c not in ':':
continue
if state.should_stop:
break
if saw_value:
# Two values without a separating comma
if isdict:
cdesc='Object'
else:
cdesc='Array'
state.push_error('Values must be separated by a comma',
position=value_position, outer_position=start_position,
context=cdesc)
saw_value = True
self.skipws(state)
if state.should_stop:
break
if isdict:
skip_item = False
key = val # Ref 11.1.5
key_position = value_position
if not helpers.isstringtype(key):
if helpers.isnumbertype(key):
state.push_cond( self.options.nonstring_keys,
'JSON only permits string literals as object properties (keys)',
position=key_position, outer_position=start_position,
context='Object')
else:
state.push_error('Object properties (keys) must be string literals, numbers, or identifiers',
position=key_position, outer_position=start_position,
context='Object')
skip_item = True
c = buf.peek()
if c != ':':
state.push_error('Missing value for object property, expected ":"',
position=value_position, outer_position=start_position,
context='Object')
buf.skip() # skip over colon
self.skipws(state)
rval = self.decodeobj(state)
self.skipws(state)
if not skip_item:
if key in obj:
state.push_cond( self.options.duplicate_keys,
'Object contains duplicate key',
key, position=key_position, outer_position=start_position,
context='Object')
if key == '':
state.push_cond( self.options.non_portable,
'Using an empty string "" as an object key may not be portable',
position=key_position, outer_position=start_position,
context='Object')
obj[ key ] = rval
num_items += 1
else: # islist
obj.append( val )
num_items += 1
# end while
if state.stats:
if isdict:
state.stats.max_items_in_object = max(state.stats.max_items_in_object, num_items)
else:
state.stats.max_items_in_array = max(state.stats.max_items_in_array, num_items)
if state.should_stop:
return obj
# Make sure composite value is properly terminated
if not done:
if isdict:
state.push_error('Object literal (dictionary) is not terminated',
outer_position=start_position, context='Object')
else:
state.push_error('Array literal (list) is not terminated',
outer_position=start_position, context='Array')
# Update stats and run hooks
if isdict:
state.stats.num_objects += 1
if self.has_hook('decode_object'):
try:
obj = self.call_hook( 'decode_object', obj, position=start_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
obj = undefined
else:
state.stats.num_arrays += 1
if self.has_hook('decode_array'):
try:
obj = self.call_hook( 'decode_array', obj, position=start_position )
except JSONSkipHook:
pass
except JSONError, err:
state.push_exception(err)
obj = undefined
return obj
def decode_javascript_identifier(self, name):
"""Convert a JavaScript identifier into a Python string object.
This method can be overriden by a subclass to redefine how JavaScript
identifiers are turned into Python objects. By default this just
converts them into strings.
"""
return name
def decodeobj(self, state, identifier_as_string=False, at_document_start=False):
"""Intermediate-level JSON decoder.
Takes a string and a starting index, and returns a two-tuple consting
of a Python object and the index of the next unparsed character.
If there is no value at all (empty string, etc), then None is
returned instead of a tuple.
"""
buf = state.buf
obj = None
self.skipws(state)
if buf.at_end:
state.push_error('Unexpected end of input')
c = buf.peek()
if c in '{[':
state.cur_depth += 1
try:
state.update_depth_stats()
obj = self.decode_composite(state)
finally:
state.cur_depth -= 1
else:
if at_document_start:
state.push_cond( self.options.any_type_at_start,
'JSON document must start with an object or array type only' )
if c in self._string_quotes:
obj = self.decode_string(state)
elif c.isdigit() or c in '.+-':
obj = self.decode_number(state)
elif c.isalpha() or c in'_$':
obj = self.decode_identifier(state, identifier_as_string=identifier_as_string)
else:
state.push_error('Can not decode value starting with character %r' % c)
buf.skip()
self.recover_parser(state)
obj = syntax_error
return obj
def decode(self, txt, encoding=None, return_errors=False, return_stats=False):
"""Decodes a JSON-encoded string into a Python object.
The 'return_errors' parameter controls what happens if the
input JSON has errors in it.
* False: the first error will be raised as a Python
exception. If there are no errors then the corresponding
Python object will be returned.
* True: the return value is always a 2-tuple: (object, error_list)
"""
import sys
state = decode_state( options=self.options )
# Prepare the input
state.set_input( txt, encoding=encoding )
# Do the decoding
if not state.has_errors:
self.__sanity_check_start( state )
if not state.has_errors:
try:
self._do_decode( state ) # DECODE!
except JSONException, err:
state.push_exception( err )
except Exception, err: # Mainly here to catch maximum recursion depth exceeded
e2 = sys.exc_info()
raise
newerr = JSONDecodeError("An unexpected failure occured", severity='fatal', position=state.buf.position)
newerr.__cause__ = err
newerr.__traceback__ = e2[2]
state.push_exception( newerr )
if return_stats and state.buf:
state.stats.num_excess_whitespace = state.buf.num_ws_skipped
state.stats.total_chars = state.buf.position.char_position
# Handle the errors
result_type = _namedtuple('json_results',['object','errors','stats'])
if return_errors:
if return_stats:
return result_type(state.obj, state.errors, state.stats)
else:
return result_type(state.obj, state.errors, None)
else:
# Don't cause warnings to raise an error
errors = [err for err in state.errors if err.severity in ('fatal','error')]
if errors:
raise errors[0]
if return_stats:
return result_type(state.obj, None, state.stats)
else:
return state.obj
def __sanity_check_start(self, state):
"""Check that the document seems sane by looking at the first couple characters.
Check that the decoding seems sane. Per RFC 4627 section 3:
"Since the first two characters of a JSON text will
always be ASCII characters [RFC0020], ..."
[WAS removed from RFC 7158, but still valid via the grammar.]
This check is probably not necessary, but it allows us to
raise a suitably descriptive error rather than an obscure
syntax error later on.
Note that the RFC requirements of two ASCII characters seems
to be an incorrect statement as a JSON string literal may have
as it's first character any unicode character. Thus the first
two characters will always be ASCII, unless the first
character is a quotation mark. And in non-strict mode we can
also have a few other characters too.
"""
is_sane = True
unitxt = state.buf.peekstr(2)
if len(unitxt) >= 2:
first, second = unitxt[:2]
if first in self._string_quotes:
pass # second can be anything inside string literal
else:
if ((ord(first) < 0x20 or ord(first) > 0x7f) or \
(ord(second) < 0x20 or ord(second) > 0x7f)) and \
(not self.isws(first) and not self.isws(second)):
# Found non-printable ascii, must check unicode
# categories to see if the character is legal.
# Only whitespace, line and paragraph separators,
# and format control chars are legal here.
import unicodedata
catfirst = unicodedata.category(unicode(first))
catsecond = unicodedata.category(unicode(second))
if catfirst not in ('Zs','Zl','Zp','Cf') or \
catsecond not in ('Zs','Zl','Zp','Cf'):
state.push_fatal( 'The input is gibberish, is the Unicode encoding correct?' )
return is_sane
def _do_decode(self, state):
"""This is the internal function that does the JSON decoding.
Called by the decode() method, after it has performed any Unicode decoding, etc.
"""
buf = state.buf
self.skipws(state)
if buf.at_end:
state.push_error('No value to decode')
else:
if state.options.decimal_context:
dec_ctx = decimal.localcontext( state.options.decimal_context )
else:
dec_ctx = _dummy_context_manager
with dec_ctx:
state.obj = self.decodeobj(state, at_document_start=True )
if not state.should_stop:
# Make sure there's nothing at the end
self.skipws(state)
if not buf.at_end:
state.push_error('Unexpected text after end of JSON value')
def _classify_for_encoding( self, obj ):
import datetime
c = 'other'
if obj is None:
c = 'null'
elif obj is undefined:
c = 'undefined'
elif isinstance(obj,bool):
c = 'bool'
elif isinstance(obj, (int,long,float,complex)) or\
(decimal and isinstance(obj, decimal.Decimal)):
c = 'number'
elif isinstance(obj, basestring) or helpers.isstringtype(obj):
c = 'string'
else:
if isinstance(obj,dict):
c = 'dict'
elif isinstance(obj,tuple) and hasattr(obj,'_asdict') and callable(obj._asdict):
# Have a named tuple
enc_nt = self.options.encode_namedtuple_as_object
if enc_nt and (enc_nt is True or (callable(enc_nt) and enc_nt(obj))):
c = 'namedtuple'
else:
c = 'sequence'
elif isinstance(obj, (list,tuple,set,frozenset)):
c = 'sequence'
elif hasattr(obj,'iterkeys') or (hasattr(obj,'__getitem__') and hasattr(obj,'keys')):
c = 'dict'
elif isinstance(obj, datetime.datetime):
# Check datetime before date because it is a subclass!
c = 'datetime'
elif isinstance(obj, datetime.date):
c = 'date'
elif isinstance(obj, datetime.time):
c = 'time'
elif isinstance(obj, datetime.timedelta):
c = 'timedelta'
elif _py_major >= 3 and isinstance(obj,(bytes,bytearray)):
c = 'bytes'
elif _py_major >= 3 and isinstance(obj,memoryview):
c = 'memoryview'
elif _enum is not None and isinstance(obj,_enum):
c = 'enum'
else:
c = 'other'
return c
def encode(self, obj, encoding=None ):
"""Encodes the Python object into a JSON string representation.
This method will first attempt to encode an object by seeing
if it has a json_equivalent() method. If so than it will
call that method and then recursively attempt to encode
the object resulting from that call.
Next it will attempt to determine if the object is a native
type or acts like a squence or dictionary. If so it will
encode that object directly.
Finally, if no other strategy for encoding the object of that
type exists, it will call the encode_default() method. That
method currently raises an error, but it could be overridden
by subclasses to provide a hook for extending the types which
can be encoded.
"""
import sys, codecs
# Make a fresh encoding state
state = encode_state( self.options )
# Find the codec to use. CodecInfo will be in 'cdk' and name in 'encoding'.
#
# Also set the state's 'escape_unicode_test' property which is used to
# determine what characters to \u-escape.
if encoding is None:
cdk = None
elif isinstance(encoding, codecs.CodecInfo):
cdk = encoding
encoding = cdk.name
else:
cdk = helpers.lookup_codec( encoding )
if not cdk:
raise JSONEncodeError('no codec available for character encoding',encoding)
if self.options.escape_unicode and callable(self.options.escape_unicode):
# User-supplied repertoire test function
state.escape_unicode_test = self.options.escape_unicode
else:
if self.options.escape_unicode==True or not cdk or cdk.name.lower() == 'ascii':
# ASCII, ISO8859-1, or and Unknown codec -- \u escape anything not ASCII
state.escape_unicode_test = lambda c: ord(c) >= 0x80
elif cdk.name == 'iso8859-1':
state.escape_unicode_test = lambda c: ord(c) >= 0x100
elif cdk and cdk.name.lower().startswith('utf'):
# All UTF-x encodings can do the whole Unicode repertoire, so
# do nothing special.
state.escape_unicode_test = False
else:
# An unusual codec. We need to test every character
# to see if it is in the codec's repertoire to determine
# if we should \u escape that character.
enc_func = cdk.encode
def escape_unicode_hardway( c ):
try:
enc_func( c )
except UnicodeEncodeError:
return True
else:
return False
state.escape_unicode_test = escape_unicode_hardway
# Make sure the encoding is not degenerate: it can encode the minimal
# number of characters needed by the JSON syntax rules.
if encoding is not None:
try:
output, nchars = cdk.encode( JSON.json_syntax_characters )
except UnicodeError, err:
raise JSONEncodeError("Output encoding %s is not sufficient to encode JSON" % cdk.name)
# Do the JSON encoding!
self._do_encode( obj, state )
if not self.options.encode_compactly:
state.append('\n')
unitxt = state.combine()
# Do the final Unicode encoding
if encoding is None:
output = unitxt
else:
try:
output, nchars = cdk.encode( unitxt )
except UnicodeEncodeError, err:
# Re-raise as a JSONDecodeError
e2 = sys.exc_info()
newerr = JSONEncodeError("a Unicode encoding error occurred")
# Simulate Python 3's: "raise X from Y" exception chaining
newerr.__cause__ = err
newerr.__traceback__ = e2[2]
raise newerr
return output
def _do_encode(self, obj, state):
"""Internal encode function."""
obj_classification = self._classify_for_encoding( obj )
if self.has_hook('encode_value'):
orig_obj = obj
try:
obj = self.call_hook( 'encode_value', obj )
except JSONSkipHook:
pass
if obj is not orig_obj:
prev_cls = obj_classification
obj_classification = self._classify_for_encoding( obj )
if obj_classification != prev_cls:
# Got a different type of object, re-encode again
self._do_encode( obj, state )
return
if hasattr(obj, 'json_equivalent'):
success = self.encode_equivalent( obj, state )
if success:
return
if obj_classification == 'null':
self.encode_null( state )
elif obj_classification == 'undefined':
if not self.options.is_forbid_undefined_values:
self.encode_undefined( state )
else:
raise JSONEncodeError('strict JSON does not permit "undefined" values')
elif obj_classification == 'bool':
self.encode_boolean( obj, state )
elif obj_classification == 'number':
try:
self.encode_number( obj, state )
except JSONEncodeError, err1:
# Bad number, probably a complex with non-zero imaginary part.
# Let the default encoders take a shot at encoding.
try:
self.try_encode_default(obj, state)
except Exception, err2:
# Default handlers couldn't deal with it, re-raise original exception.
raise err1
elif obj_classification == 'string':
self.encode_string( obj, state )
elif obj_classification == 'enum': # Python 3.4 enum.Enum
self.encode_enum( obj, state )
elif obj_classification == 'datetime': # Python datetime.datetime
self.encode_datetime( obj, state )
elif obj_classification == 'date': # Python datetime.date
self.encode_date( obj, state )
elif obj_classification == 'time': # Python datetime.time
self.encode_time( obj, state )
elif obj_classification == 'timedelta': # Python datetime.time
self.encode_timedelta( obj, state )
else:
# Anything left is probably composite, or an unconvertable type.
self.encode_composite( obj, state )
def encode_enum(self, val, state):
"""Encode a Python Enum value into JSON."""
eas = self.options.encode_enum_as
if eas == 'qname':
self.encode_string( str(obj), state )
elif eas == 'value':
self._do_encode( obj.value, state )
else: # eas == 'name'
self.encode_string( obj.name, state )
def encode_date(self, dt, state):
fmt = self.options.date_format
if not fmt or fmt == 'iso':
fmt = '%Y-%m-%d'
self.encode_string( dt.strftime(fmt), state )
def encode_datetime(self, dt, state):
fmt = self.options.datetime_format
is_iso = not fmt or fmt == 'iso'
if is_iso:
if dt.microsecond == 0:
fmt = '%Y-%m-%dT%H:%M:%S%z'
else:
fmt = '%Y-%m-%dT%H:%M:%S.%f%z'
s = dt.strftime(fmt)
if is_iso and s.endswith('-00:00') or s.endswith('+00:00'):
s = s[:-6] + 'Z' # Change UTC to use 'Z' notation
self.encode_string( s, state )
def encode_time(self, t, state):
fmt = self.options.datetime_format
is_iso = not fmt or fmt == 'iso'
if is_iso:
if dt.microsecond == 0:
fmt = 'T%H:%M:%S%z'
else:
fmt = 'T%H:%M:%S.%f%z'
s = t.strftime(fmt)
if is_iso and s.endswith('-00:00') or s.endswith('+00:00'):
s = s[:-6] + 'Z' # Change UTC to use 'Z' notation
self.encode_string( s, state )
def encode_timedelta(self, td, state):
fmt = self.options.timedelta_format
if not fmt or fmt == 'iso':
s = helpers.format_timedelta_iso( td )
elif fmt == 'hms':
s = str(td)
else:
raise ValueError("Unknown timedelta_format %r" % fmt)
self.encode_string( s, state )
def encode_composite(self, obj, state, obj_classification=None):
"""Encodes just composite objects: dictionaries, lists, or sequences.
Basically handles any python type for which iter() can create
an iterator object.
This method is not intended to be called directly. Use the
encode() method instead.
"""
import sys
if not obj_classification:
obj_classification = self._classify_for_encoding(obj)
# Convert namedtuples to dictionaries
if obj_classification == 'namedtuple':
obj = obj._asdict()
obj_classification = 'dict'
# Convert 'unsigned byte' memory views into plain bytes
if obj_classification == 'memoryview' and obj.format == 'B':
obj = obj.tobytes()
obj_classification = 'bytes'
# Run hooks
hook_name = None
if obj_classification == 'dict':
hook_name = 'encode_dict'
elif obj_classification == 'sequence':
hook_name = 'encode_sequence'
elif obj_classification == 'bytes':
hook_name = 'encode_bytes'
if self.has_hook(hook_name):
try:
new_obj = self.call_hook( hook_name, obj )
except JSONSkipHook:
pass
else:
if new_obj is not obj:
obj = new_obj
prev_cls = obj_classification
obj_classification = self._classify_for_encoding( obj )
if obj_classification != prev_cls:
# Transformed to a different kind of object, call
# back to the general encode() method.
self._do_encode( obj, state )
return
# Else, fall through
# At his point we have decided to do with an object or an array
isdict = (obj_classification == 'dict')
# Get iterator
it = None
if isdict and hasattr(obj,'iterkeys'):
try:
it = obj.iterkeys()
except AttributeError:
pass
else:
try:
it = iter(obj)
except TypeError:
pass
# Convert each member to JSON
if it is not None:
# Try to get length, but don't fail if we can't
try:
numitems = len(obj)
except TypeError:
numitems = 0
# Output the opening bracket or brace
compactly = self.options.encode_compactly
if not compactly:
indent0 = self.options.indentation_for_level( state.nest_level )
indent = self.options.indentation_for_level( state.nest_level+1 )
spaces_after_opener = ''
if isdict:
opener = '{'
closer = '}'
if compactly:
dictcolon = ':'
else:
dictcolon = ' : '
else:
opener = '['
closer = ']'
if not compactly:
#opener = opener + ' '
spaces_after_opener = self.options.spaces_to_next_indent_level(subtract=len(opener))
state.append( opener )
state.append( spaces_after_opener )
# Now iterate through all the items and collect their representations
parts = [] # Collects each of the members
part_keys = [] # For dictionary key sorting, tuples (key,index)
try: # while not StopIteration
part_idx = 0
while True:
obj2 = it.next()
part_idx += 1 # Note, will start counting at 1
if obj2 is obj:
raise JSONEncodeError('trying to encode an infinite sequence',obj)
if isdict:
obj3 = obj[obj2]
# Dictionary key is in obj2 and value in obj3.
# Let any hooks transform the key.
if self.has_hook('encode_value'):
try:
newobj = self.call_hook( 'encode_value', obj2 )
except JSONSkipHook:
pass
else:
obj2 = newobj
if self.has_hook('encode_dict_key'):
try:
newkey = self.call_hook( 'encode_dict_key', obj2 )
except JSONSkipHook:
pass
else:
obj2 = newkey
# Check JSON restrictions on key types
if not helpers.isstringtype(obj2):
if helpers.isnumbertype(obj2):
if not self.options.is_allow_nonstring_keys:
raise JSONEncodeError('object properties (dictionary keys) must be strings in strict JSON',obj2)
else:
raise JSONEncodeError('object properties (dictionary keys) can only be strings or numbers in ECMAScript',obj2)
part_keys.append( (obj2, part_idx-1) )
# Encode this item in the sequence and put into item_chunks
substate = state.make_substate()
self._do_encode( obj2, substate )
if isdict:
substate.append( dictcolon )
substate2 = substate.make_substate()
self._do_encode( obj3, substate2 )
substate.join_substate( substate2 )
parts.append( substate )
# Next item iteration
except StopIteration:
pass
# Sort dictionary keys
if isdict:
srt = self.options.sort_keys
if srt == SORT_PRESERVE:
if _OrderedDict and isinstance(obj,_OrderedDict):
srt = SORT_NONE # Will keep order
else:
srt = SORT_SMART
if not srt or srt in (SORT_NONE, SORT_PRESERVE):
srt = None
elif callable(srt):
part_keys.sort( key=(lambda t: (srt(t[0]),t[0])) )
elif srt == SORT_SMART:
part_keys.sort( key=(lambda t: (smart_sort_transform(t[0]),t[0])) )
elif srt == SORT_ALPHA_CI:
part_keys.sort( key=(lambda t: (unicode(t[0]).upper(),t[0])) )
elif srt or srt == SORT_ALPHA:
part_keys.sort( key=(lambda t: unicode(t[0])) )
# Now make parts match the new sort order
if srt is not None:
parts = [parts[pk[1]] for pk in part_keys]
if compactly:
sep = ','
elif len(parts) <= self.options.max_items_per_line:
sep = ', '
else:
#state.append(spaces_after_opener)
state.append('\n' + indent)
sep = ',\n' + indent
for pnum, substate in enumerate(parts):
if pnum > 0:
state.append( sep )
state.join_substate( substate )
if not compactly:
if numitems > self.options.max_items_per_line:
state.append('\n' + indent0)
else:
state.append(' ')
state.append(closer) # final '}' or ']'
else: # Can't create an iterator for the object
self.try_encode_default( obj, state )
def encode_equivalent( self, obj, state ):
"""This method is used to encode user-defined class objects.
The object being encoded should have a json_equivalent()
method defined which returns another equivalent object which
is easily JSON-encoded. If the object in question has no
json_equivalent() method available then None is returned
instead of a string so that the encoding will attempt the next
strategy.
If a caller wishes to disable the calling of json_equivalent()
methods, then subclass this class and override this method
to just return None.
"""
if hasattr(obj, 'json_equivalent') \
and callable(getattr(obj,'json_equivalent')):
obj2 = obj.json_equivalent()
if obj2 is obj:
# Try to prevent careless infinite recursion
raise JSONEncodeError('object has a json_equivalent() method that returns itself',obj)
self._do_encode( obj2, state )
return True
else:
return False
def try_encode_default( self, obj, state ):
orig_obj = obj
if self.has_hook('encode_default'):
try:
obj = self.call_hook( 'encode_default', obj )
except JSONSkipHook:
pass
else:
if obj is not orig_obj:
# Hook made a transformation, re-encode it
return self._do_encode( obj, state )
# End of the road.
raise JSONEncodeError('can not encode object into a JSON representation',obj)
# ------------------------------
def encode( obj, encoding=None, **kwargs ):
r"""Encodes a Python object into a JSON-encoded string.
* 'strict' (Boolean, default False)
If 'strict' is set to True, then only strictly-conforming JSON
output will be produced. Note that this means that some types
of values may not be convertable and will result in a
JSONEncodeError exception.
* 'compactly' (Boolean, default True)
If 'compactly' is set to True, then the resulting string will
have all extraneous white space removed; if False then the
string will be "pretty printed" with whitespace and
indentation added to make it more readable.
* 'encode_namedtuple_as_object' (Boolean or callable, default True)
If True, then objects of type namedtuple, or subclasses of
'tuple' that have an _asdict() method, will be encoded as an
object rather than an array.
If can also be a predicate function that takes a namedtuple
object as an argument and returns True or False.
* 'indent_amount' (Integer, default 2)
The number of spaces to output for each indentation level.
If 'compactly' is True then indentation is ignored.
* 'indent_limit' (Integer or None, default None)
If not None, then this is the maximum limit of indentation
levels, after which further indentation spaces are not
inserted. If None, then there is no limit.
CONCERNING CHARACTER ENCODING:
The 'encoding' argument should be one of:
* None - The return will be a Unicode string.
* encoding_name - A string which is the name of a known
encoding, such as 'UTF-8' or 'ascii'.
* codec - A CodecInfo object, such as as found by codecs.lookup().
This allows you to use a custom codec as well as those
built into Python.
If an encoding is given (either by name or by codec), then the
returned value will be a byte array (Python 3), or a 'str' string
(Python 2); which represents the raw set of bytes. Otherwise,
if encoding is None, then the returned value will be a Unicode
string.
The 'escape_unicode' argument is used to determine which characters
in string literals must be \u escaped. Should be one of:
* True -- All non-ASCII characters are always \u escaped.
* False -- Try to insert actual Unicode characters if possible.
* function -- A user-supplied function that accepts a single
unicode character and returns True or False; where True
means to \u escape that character.
Regardless of escape_unicode, certain characters will always be
\u escaped. Additionaly any characters not in the output encoding
repertoire for the encoding codec will be \u escaped as well.
"""
# Do the JSON encoding
j = JSON( **kwargs )
output = j.encode( obj, encoding )
return output
def decode( txt, encoding=None, **kwargs ):
"""Decodes a JSON-encoded string into a Python object.
== Optional arguments ==
* 'encoding' (string, default None)
This argument provides a hint regarding the character encoding
that the input text is assumed to be in (if it is not already a
unicode string type).
If set to None then autodetection of the encoding is attempted
(see discussion above). Otherwise this argument should be the
name of a registered codec (see the standard 'codecs' module).
* 'strict' (Boolean, default False)
If 'strict' is set to True, then those strings that are not
entirely strictly conforming to JSON will result in a
JSONDecodeError exception.
* 'return_errors' (Boolean, default False)
Controls the return value from this function. If False, then
only the Python equivalent object is returned on success, or
an error will be raised as an exception.
If True then a 2-tuple is returned: (object, error_list). The
error_list will be an empty list [] if the decoding was
successful, otherwise it will be a list of all the errors
encountered. Note that it is possible for an object to be
returned even if errors were encountered.
* 'return_stats' (Boolean, default False)
Controls whether statistics about the decoded JSON document
are returns (and instance of decode_statistics).
If True, then the stats object will be added to the end of the
tuple returned. If return_errors is also set then a 3-tuple
is returned, otherwise a 2-tuple is returned.
* 'write_errors' (Boolean OR File-like object, default False)
Controls what to do with errors.
- If False, then the first decoding error is raised as an exception.
- If True, then errors will be printed out to sys.stderr.
- If a File-like object, then errors will be printed to that file.
The write_errors and return_errors arguments can be set
independently.
* 'filename_for_errors' (string or None)
Provides a filename to be used when writting error messages.
* 'allow_xxx', 'warn_xxx', and 'forbid_xxx' (Booleans)
These arguments allow for fine-adjustments to be made to the
'strict' argument, by allowing or forbidding specific
syntaxes.
There are many of these arguments, named by replacing the
"xxx" with any number of possible behavior names (See the JSON
class for more details).
Each of these will allow (or forbid) the specific behavior,
after the evaluation of the 'strict' argument. For example,
if strict=True then by also passing 'allow_comments=True' then
comments will be allowed. If strict=False then
forbid_comments=True will allow everything except comments.
Unicode decoding:
-----------------
The input string can be either a python string or a python unicode
string (or a byte array in Python 3). If it is already a unicode
string, then it is assumed that no character set decoding is
required.
However, if you pass in a non-Unicode text string (a Python 2
'str' type or a Python 3 'bytes' or 'bytearray') then an attempt
will be made to auto-detect and decode the character encoding.
This will be successful if the input was encoded in any of UTF-8,
UTF-16 (BE or LE), or UTF-32 (BE or LE), and of course plain ASCII
works too.
Note though that if you know the character encoding, then you
should convert to a unicode string yourself, or pass it the name
of the 'encoding' to avoid the guessing made by the auto
detection, as with
python_object = demjson.decode( input_bytes, encoding='utf8' )
Callback hooks:
---------------
You may supply callback hooks by using the hook name as the
named argument, such as:
decode_float=decimal.Decimal
See the hooks documentation on the JSON.set_hook() method.
"""
import sys
# Initialize the JSON object
return_errors = False
return_stats = False
write_errors = False
filename_for_errors = None
write_stats = False
kwargs = kwargs.copy()
todel = []
for kw,val in kwargs.items():
if kw == "return_errors":
return_errors = bool(val)
todel.append(kw)
elif kw == 'return_stats':
return_stats = bool(val)
todel.append(kw)
elif kw == "write_errors":
write_errors = val
todel.append(kw)
elif kw == "filename_for_errors":
filename_for_errors = val
todel.append(kw)
elif kw == "write_stats":
write_stats = val
todel.append(kw)
# next keyword argument
for kw in todel:
del kwargs[kw]
j = JSON( **kwargs )
# Now do the actual JSON decoding
result = j.decode( txt,
encoding=encoding,
return_errors=(return_errors or write_errors),
return_stats=(return_stats or write_stats) )
if write_errors:
import sys
if write_errors is True:
write_errors = sys.stderr
for err in result.errors:
write_errors.write( err.pretty_description(filename=filename_for_errors) + "\n" )
if write_stats:
import sys
if write_stats is True:
write_stats = sys.stderr
if result.stats:
write_stats.write( "%s----- Begin JSON statistics\n" % filename_for_errors )
write_stats.write( result.stats.pretty_description( prefix=" | " ) )
write_stats.write( "%s----- End of JSON statistics\n" % filename_for_errors )
return result
def encode_to_file( filename, obj, encoding='utf-8', overwrite=False, **kwargs ):
"""Encodes a Python object into JSON and writes into the given file.
If no encoding is given, then UTF-8 will be used.
See the encode() function for a description of other possible options.
If the file already exists and the 'overwrite' option is not set
to True, then the existing file will not be overwritten. (Note,
there is a subtle race condition in the check so there are
possible conditions in which a file may be overwritten)
"""
import os, errno
if not encoding:
encoding = 'utf-8'
if not isinstance(filename,basestring) or not filename:
raise TypeError("Expected a file name")
if not overwrite and os.path.exists(filename):
raise IOError(errno.EEXIST, "File exists: %r" % filename)
jsondata = encode( obj, encoding=encoding, **kwargs )
try:
fp = open(filename, 'wb')
except Exception:
raise
else:
try:
fp.write( jsondata )
finally:
fp.close()
def decode_file( filename, encoding=None, **kwargs ):
"""Decodes JSON found in the given file.
See the decode() function for a description of other possible options.
"""
if isinstance(filename,basestring):
try:
fp = open(filename, 'rb')
except Exception:
raise
else:
try:
jsondata = fp.read()
finally:
fp.close()
else:
raise TypeError("Expected a file name")
return decode( jsondata, encoding=encoding, **kwargs )
# ======================================================================
class jsonlint(object):
"""This class contains most of the logic for the "jsonlint" command.
You generally create an instance of this class, to defined the
program's environment, and then call the main() method. A simple
wrapper to turn this into a script might be:
import sys, demjson
if __name__ == '__main__':
lint = demjson.jsonlint( sys.argv[0] )
return lint.main( sys.argv[1:] )
"""
_jsonlint_usage = r"""Usage: %(program_name)s [ ...] [--] inputfile.json ...
With no input filename, or "-", it will read from standard input.
The return status will be 0 if the file is conforming JSON (per the
RFC 7159 specification), or non-zero otherwise.
GENERAL OPTIONS:
-v | --verbose Show details of lint checking
-q | --quiet Don't show any output (except for reformatting)
STRICTNESS OPTIONS (WARNINGS AND ERRORS):
-W | --tolerant Be tolerant, but warn about non-conformance (default)
-s | --strict Be strict in what is considered conforming JSON
-S | --nonstrict Be tolerant in what is considered conforming JSON
--allow=... -\
--warn=... |-- These options let you pick specific behaviors.
--forbid=... -/ Use --help-behaviors for more
STATISTICS OPTIONS:
--stats Show statistics about JSON document
REFORMATTING OPTIONS:
-f | --format Reformat the JSON text (if conforming) to stdout
-F | --format-compactly
Reformat the JSON simlar to -f, but do so compactly by
removing all unnecessary whitespace
-o filename | --output filename
The filename to which reformatted JSON is to be written.
Without this option the standard output is used.
--[no-]keep-format Try to preserve numeric radix, e.g., hex, octal, etc.
--html-safe Escape characters that are not safe to embed in HTML/XML.
--sort How to sort object/dictionary keys, is one of:
%(sort_options_help)s
--indent tabs | Number of spaces to use per indentation level,
or use tab characters if "tabs" given.
UNICODE OPTIONS:
-e codec | --encoding=codec Set both input and output encodings
--input-encoding=codec Set the input encoding
--output-encoding=codec Set the output encoding
These options set the character encoding codec (e.g., "ascii",
"utf-8", "utf-16"). The -e will set both the input and output
encodings to the same thing. The output encoding is used when
reformatting with the -f or -F options.
Unless set, the input encoding is guessed and the output
encoding will be "utf-8".
OTHER OPTIONS:
--recursion-limit=nnn Set the Python recursion limit to number
--leading-zero-radix=8|10 The radix to use for numbers with leading
zeros. 8=octal, 10=decimal.
REFORMATTING / PRETTY-PRINTING:
When reformatting JSON with -f or -F, output is only produced if
the input passed validation. By default the reformatted JSON will
be written to standard output, unless the -o option was given.
The default output codec is UTF-8, unless an encoding option is
provided. Any Unicode characters will be output as literal
characters if the encoding permits, otherwise they will be
\u-escaped. You can use "--output-encoding ascii" to force all
Unicode characters to be escaped.
MORE INFORMATION:
Use '%(program_name)s --version [-v]' to see versioning information.
Use '%(program_name)s --copyright' to see author and copyright details.
Use '%(program_name)s [-W|-s|-S] --help-behaviors' for help on specific checks.
%(program_name)s is distributed as part of the "demjson" Python module.
See %(homepage)s
"""
SUCCESS_FAIL = 'E'
SUCCESS_WARNING = 'W'
SUCCESS_OK = 'OK'
def __init__(self, program_name='jsonlint', stdin=None, stdout=None, stderr=None ):
"""Create an instance of a "jsonlint" program.
You can optionally pass options to define the program's environment:
* program_name - the name of the program, usually sys.argv[0]
* stdin - the file object to use for input, default sys.stdin
* stdout - the file object to use for outut, default sys.stdout
* stderr - the file object to use for error output, default sys.stderr
After creating an instance, you typically call the main() method.
"""
import os, sys
self.program_path = program_name
self.program_name = os.path.basename(program_name)
if stdin:
self.stdin = stdin
else:
self.stdin = sys.stdin
if stdout:
self.stdout = stdout
else:
self.stdout = sys.stdout
if stderr:
self.stderr = stderr
else:
self.stderr = sys.stderr
@property
def usage(self):
"""A multi-line string containing the program usage instructions.
"""
sorthelp = '\n'.join([
" %12s - %s" % (sm, sd)
for sm, sd in sorted(sorting_methods.items()) if sm != SORT_NONE ])
return self._jsonlint_usage % {'program_name':self.program_name,
'homepage':__homepage__,
'sort_options_help': sorthelp }
def _lintcheck_data( self,
jsondata,
verbose_fp=None,
reformat=False,
show_stats=False,
input_encoding=None, output_encoding=None, escape_unicode=True,
pfx='',
jsonopts=None ):
global decode, encode
success = self.SUCCESS_FAIL
reformatted = None
if show_stats:
stats_fp = verbose_fp
else:
stats_fp = None
try:
results = decode( jsondata, encoding=input_encoding,
return_errors=True,
return_stats=True,
write_errors=verbose_fp,
write_stats=stats_fp,
filename_for_errors=pfx,
json_options=jsonopts )
except JSONError, err:
success = self.SUCCESS_FAIL
if verbose_fp:
verbose_fp.write('%s%s\n' % (pfx, err.pretty_description()) )
except Exception, err:
success = self.SUCCESS_FAIL
if verbose_fp:
verbose_fp.write('%s%s\n' % (pfx, str(err) ))
else:
errors = [err for err in results.errors if err.severity in ('fatal','error')]
warnings = [err for err in results.errors if err.severity in ('warning',)]
if errors:
success = self.SUCCESS_FAIL
elif warnings:
success = self.SUCCESS_WARNING
else:
success = self.SUCCESS_OK
if reformat:
encopts = jsonopts.copy()
encopts.strictness = STRICTNESS_TOLERANT
if reformat == 'compactly':
encopts.encode_compactly = True
else:
encopts.encode_compactly = False
reformatted = encode(results.object, encoding=output_encoding, json_options=encopts)
return (success, reformatted)
def _lintcheck( self, filename, output_filename,
verbose=False,
reformat=False,
show_stats=False,
input_encoding=None, output_encoding=None, escape_unicode=True,
jsonopts=None ):
import sys
verbose_fp = None
if not filename or filename == "-":
pfx = ': '
jsondata = self.stdin.read()
if verbose:
verbose_fp = self.stderr
else:
pfx = '%s: ' % filename
try:
fp = open( filename, 'rb' )
jsondata = fp.read()
fp.close()
except IOError, err:
self.stderr.write('%s: %s\n' % (pfx, str(err)) )
return self.SUCCESS_FAIL
if verbose:
verbose_fp = self.stdout
success, reformatted = self._lintcheck_data(
jsondata,
verbose_fp=verbose_fp,
reformat=reformat,
show_stats=show_stats,
input_encoding=input_encoding, output_encoding=output_encoding,
pfx=pfx,
jsonopts=jsonopts )
if success != self.SUCCESS_FAIL and reformat:
if output_filename:
try:
fp = open( output_filename, 'wb' )
fp.write( reformatted )
except IOError, err:
self.stderr.write('%s: %s\n' % (pfx, str(err)) )
success = False
else:
if hasattr(sys.stdout,'buffer'): # To write binary data rather than strings
self.stdout.buffer.write( reformatted )
else:
self.stdout.write( reformatted )
elif success == self.SUCCESS_OK and verbose_fp:
verbose_fp.write('%sok\n' % pfx)
elif success == self.SUCCESS_WARNING and verbose_fp:
verbose_fp.write('%sok, with warnings\n' % pfx)
elif verbose_fp:
verbose_fp.write("%shas errors\n" % pfx)
return success
def main( self, argv ):
"""The main routine for program "jsonlint".
Should be called with sys.argv[1:] as its sole argument.
Note sys.argv[0] which normally contains the program name
should not be passed to main(); instead this class itself
is initialized with sys.argv[0].
Use "--help" for usage syntax, or consult the 'usage' member.
"""
import sys, os, getopt, unicodedata
recursion_limit = None
success = True
verbose = 'auto' # one of 'auto', True, or False
reformat = False
show_stats = False
output_filename = None
input_encoding = None
output_encoding = 'utf-8'
kwoptions = { # Will be used to initialize json_options
"sort_keys": SORT_SMART,
"strict": STRICTNESS_WARN,
"keep_format": True,
"decimal_context": 100,
}
try:
opts, args = getopt.getopt( argv,
'vqfFe:o:sSW',
['verbose','quiet',
'format','format-compactly',
'stats',
'output',
'strict','nonstrict','warn',
'html-safe','xml-safe',
'encoding=',
'input-encoding=','output-encoding=',
'sort=',
'recursion-limit=',
'leading-zero-radix=',
'keep-format',
'no-keep-format',
'indent=',
'indent-amount=',
'indent-limit=',
'indent-tab-width=',
'max-items-per-line=',
'allow=', 'warn=', 'forbid=', 'deny=',
'help', 'help-behaviors',
'version','copyright'] )
except getopt.GetoptError, err:
self.stderr.write( "Error: %s. Use \"%s --help\" for usage information.\n" \
% (err.msg, self.program_name) )
return 1
# Set verbose before looking at any other options
for opt, val in opts:
if opt in ('-v', '--verbose'):
verbose=True
# Process all options
for opt, val in opts:
if opt in ('-h', '--help'):
self.stdout.write( self.usage )
return 0
elif opt == '--help-behaviors':
self.stdout.write("""
BEHAVIOR OPTIONS:
These set of options let you control which checks are to be performed.
They may be turned on or off by listing them as arguments to one of
the options --allow, --warn, or --forbid ; for example:
%(program_name)s --allow comments,hex-numbers --forbid duplicate-keys
""" % {"program_name":self.program_name})
self.stdout.write("The default shown is for %s mode\n\n" % kwoptions['strict'])
self.stdout.write('%-7s %-25s %s\n' % ("Default", "Behavior_name", "Description"))
self.stdout.write('-'*7 + ' ' + '-'*25 + ' ' + '-'*50 + '\n')
j = json_options( **kwoptions )
for behavior in sorted(j.all_behaviors):
v = j.get_behavior( behavior )
desc = j.describe_behavior( behavior )
self.stdout.write('%-7s %-25s %s\n' % (v.lower(), behavior.replace('_','-'), desc))
return 0
elif opt == '--version':
self.stdout.write( '%s (%s) version %s (%s)\n' \
% (self.program_name, __name__, __version__, __date__) )
if verbose == True:
self.stdout.write( 'demjson from %r\n' % (__file__,) )
if verbose == True:
self.stdout.write( 'Python version: %s\n' % (sys.version.replace('\n',' '),) )
self.stdout.write( 'This python implementation supports:\n' )
self.stdout.write( ' * Max unicode: U+%X\n' % (sys.maxunicode,) )
self.stdout.write( ' * Unicode version: %s\n' % (unicodedata.unidata_version,) )
self.stdout.write( ' * Floating-point significant digits: %d\n' % (float_sigdigits,) )
self.stdout.write( ' * Floating-point max 10^exponent: %d\n' % (float_maxexp,) )
if str(0.0)==str(-0.0):
szero = 'No'
else:
szero = 'Yes'
self.stdout.write( ' * Floating-point has signed-zeros: %s\n' % (szero,) )
if decimal:
has_dec = 'Yes'
else:
has_dec = 'No'
self.stdout.write( ' * Decimal (bigfloat) support: %s\n' % (has_dec,) )
return 0
elif opt == '--copyright':
self.stdout.write( "%s is distributed as part of the \"demjson\" python package.\n" \
% (self.program_name,) )
self.stdout.write( "See %s\n\n\n" % (__homepage__,) )
self.stdout.write( __credits__ )
return 0
elif opt in ('-v', '--verbose'):
verbose = True
elif opt in ('-q', '--quiet'):
verbose = False
elif opt in ('-s', '--strict'):
kwoptions['strict'] = STRICTNESS_STRICT
kwoptions['keep_format'] = False
elif opt in ('-S', '--nonstrict'):
kwoptions['strict'] = STRICTNESS_TOLERANT
elif opt in ('-W', '--tolerant'):
kwoptions['strict'] = STRICTNESS_WARN
elif opt in ('-f', '--format'):
reformat = True
kwoptions['encode_compactly'] = False
elif opt in ('-F', '--format-compactly'):
kwoptions['encode_compactly'] = True
reformat = 'compactly'
elif opt in ('--stats',):
show_stats=True
elif opt in ('-o', '--output'):
output_filename = val
elif opt in ('-e','--encoding'):
input_encoding = val
output_encoding = val
escape_unicode = False
elif opt in ('--output-encoding'):
output_encoding = val
escape_unicode = False
elif opt in ('--input-encoding'):
input_encoding = val
elif opt in ('--html-safe','--xml-safe'):
kwoptions['html_safe'] = True
elif opt in ('--allow','--warn','--forbid'):
action = opt[2:]
if action in kwoptions:
kwoptions[action] += "," + val
else:
kwoptions[action] = val
elif opt in ('--keep-format',):
kwoptions['keep_format']=True
elif opt in ('--no-keep-format',):
kwoptions['keep_format']=False
elif opt == '--leading-zero-radix':
kwoptions['leading_zero_radix'] = val
elif opt in ('--indent', '--indent-amount'):
if val in ('tab','tabs'):
kwoptions['indent_amount'] = 8
kwoptions['indent_tab_width'] = 8
else:
try:
kwoptions['indent_amount'] = int(val)
except ValueError:
self.stderr.write("Indentation amount must be a number\n")
return 1
elif opt == 'indent-tab-width':
try:
kwoptions['indent_tab_width'] = int(val)
except ValueError:
self.stderr.write("Indentation tab width must be a number\n")
return 1
elif opt == '--max-items-per-line':
try:
kwoptions['max_items_per_line'] = int(val)
except ValueError:
self.stderr.write("Max items per line must be a number\n")
return 1
elif opt == '--sort':
val = val.lower()
if val == 'alpha':
kwoptions['sort_keys'] = SORT_ALPHA
elif val == 'alpha_ci':
kwoptions['sort_keys'] = SORT_ALPHA_CI
elif val == 'preserve':
kwoptions['sort_keys'] = SORT_PRESERVE
else:
kwoptions['sort_keys'] = SORT_SMART
elif opt == '--recursion-limit':
try:
recursion_limit = int(val)
except ValueError:
self.stderr.write("Recursion limit must be a number: %r\n" % val)
return 1
else:
max_limit = 100000
old_limit = sys.getrecursionlimit()
if recursion_limit > max_limit:
self.stderr.write("Recursion limit must be a number between %d and %d\n" % (old_limit,max_limit))
return 1
elif recursion_limit > old_limit:
sys.setrecursionlimit( recursion_limit )
else:
self.stderr.write('Unknown option %r\n' % opt)
return 1
# Make the JSON options
kwoptions['decimal_context'] = 100
jsonopts = json_options( **kwoptions )
# Now decode each file...
if not args:
args = [None]
for fn in args:
try:
rc = self._lintcheck( fn, output_filename=output_filename,
verbose=verbose,
reformat=reformat,
show_stats=show_stats,
input_encoding=input_encoding,
output_encoding=output_encoding,
jsonopts=jsonopts )
if rc != self.SUCCESS_OK:
# Warnings or errors should result in failure. If
# checking multiple files, do not change a
# previous error back to ok.
success = False
except KeyboardInterrupt, err:
sys.stderr.write("\njsonlint interrupted!\n")
sys.exit(1)
if not success:
return 1
return 0
# end file