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## json.py implements a JSON (http://json.org) reader and writer.
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## Copyright (C) 2005 Patrick D. Logan
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## Contact mailto:patrickdlogan@stardecisions.com
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## This library is free software; you can redistribute it and/or
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## modify it under the terms of the GNU Lesser General Public
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## License as published by the Free Software Foundation; either
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## version 2.1 of the License, or (at your option) any later version.
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## This library is distributed in the hope that it will be useful,
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## but WITHOUT ANY WARRANTY; without even the implied warranty of
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## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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## Lesser General Public License for more details.
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## You should have received a copy of the GNU Lesser General Public
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## License along with this library; if not, write to the Free Software
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## Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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class _StringGenerator(object):
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def __init__(self, string):
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if i < len(self.string):
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if self.index < len(self.string):
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return self.string[self.index]
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class WriteException(Exception):
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class ReadException(Exception):
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class JsonReader(object):
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hex_digits = {'A': 10,'B': 11,'C': 12,'D': 13,'E': 14,'F':15}
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escapes = {'t':'\t','n':'\n','f':'\f','r':'\r','b':'\b'}
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self._generator = _StringGenerator(s)
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raise ReadException, "Nothing to read: '%s'" % self._generator.all()
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return self._readObject()
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return self._readArray()
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return self._readString()
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elif peek == '-' or peek.isdigit():
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return self._readNumber()
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return self._readTrue()
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return self._readFalse()
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return self._readNull()
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raise ReadException, "Input is not valid JSON: '%s'" % self._generator.all()
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self._assertNext('t', "true")
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self._assertNext('r', "true")
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self._assertNext('u', "true")
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self._assertNext('e', "true")
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self._assertNext('f', "false")
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self._assertNext('a', "false")
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self._assertNext('l', "false")
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self._assertNext('s', "false")
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self._assertNext('e', "false")
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self._assertNext('n', "null")
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self._assertNext('u', "null")
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self._assertNext('l', "null")
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self._assertNext('l', "null")
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def _assertNext(self, ch, target):
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if self._next() != ch:
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raise ReadException, "Trying to read %s: '%s'" % (target, self._generator.all())
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def _readNumber(self):
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result = self._next()
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while peek is not None and (peek.isdigit() or peek == "."):
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isfloat = isfloat or peek == "."
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result = result + self._next()
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raise ReadException, "Not a valid JSON number: '%s'" % result
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def _readString(self):
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assert self._next() == '"'
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while self._peek() != '"':
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ch = self.escapes[ch]
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ch4096 = self._next()
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n = 4096 * self._hexDigitToInt(ch4096)
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n += 256 * self._hexDigitToInt(ch256)
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n += 16 * self._hexDigitToInt(ch16)
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n += self._hexDigitToInt(ch1)
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elif ch not in '"/\\':
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raise ReadException, "Not a valid escaped JSON character: '%s' in %s" % (ch, self._generator.all())
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except StopIteration:
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raise ReadException, "Not a valid JSON string: '%s'" % self._generator.all()
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assert self._next() == '"'
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def _hexDigitToInt(self, ch):
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result = self.hex_digits[ch.upper()]
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raise ReadException, "The character %s is not a hex digit." % ch
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def _readComment(self):
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assert self._next() == "/"
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second = self._next()
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self._readDoubleSolidusComment()
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self._readCStyleComment()
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raise ReadException, "Not a valid JSON comment: %s" % self._generator.all()
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def _readCStyleComment(self):
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done = (ch == "*" and self._peek() == "/")
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if not done and ch == "/" and self._peek() == "*":
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raise ReadException, "Not a valid JSON comment: %s, '/*' cannot be embedded in the comment." % self._generator.all()
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except StopIteration:
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raise ReadException, "Not a valid JSON comment: %s, expected */" % self._generator.all()
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def _readDoubleSolidusComment(self):
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while ch != "\r" and ch != "\n":
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except StopIteration:
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def _readArray(self):
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assert self._next() == '['
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done = self._peek() == ']'
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self._eatWhitespace()
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done = self._peek() == ']'
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raise ReadException, "Not a valid JSON array: '%s' due to: '%s'" % (self._generator.all(), ch)
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assert ']' == self._next()
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def _readObject(self):
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assert self._next() == '{'
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done = self._peek() == '}'
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if type(key) is not types.StringType:
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raise ReadException, "Not a valid JSON object key (should be a string): %s" % key
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self._eatWhitespace()
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raise ReadException, "Not a valid JSON object: '%s' due to: '%s'" % (self._generator.all(), ch)
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self._eatWhitespace()
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self._eatWhitespace()
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done = self._peek() == '}'
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raise ReadException, "Not a valid JSON array: '%s' due to: '%s'" % (self._generator.all(), ch)
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assert self._next() == "}"
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def _eatWhitespace(self):
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while p is not None and p in string.whitespace or p == '/':
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return self._generator.peek()
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return self._generator.next()
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class JsonWriter(object):
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def _append(self, s):
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self._results.append(s)
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def write(self, obj, escaped_forward_slash=False):
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self._escaped_forward_slash = escaped_forward_slash
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return "".join(self._results)
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def _write(self, obj):
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if ty is types.DictType:
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for k, v in obj.items():
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elif ty is types.ListType or ty is types.TupleType:
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elif ty is types.StringType or ty is types.UnicodeType:
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obj = obj.replace('\\', r'\\')
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if self._escaped_forward_slash:
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obj = obj.replace('/', r'\/')
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obj = obj.replace('"', r'\"')
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obj = obj.replace('\b', r'\b')
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obj = obj.replace('\f', r'\f')
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obj = obj.replace('\n', r'\n')
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obj = obj.replace('\r', r'\r')
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obj = obj.replace('\t', r'\t')
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elif ty is types.IntType or ty is types.LongType:
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self._append(str(obj))
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elif ty is types.FloatType:
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self._append("%f" % obj)
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self._append("false")
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raise WriteException, "Cannot write in JSON: %s" % repr(obj)
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def write(obj, escaped_forward_slash=False):
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return JsonWriter().write(obj, escaped_forward_slash)
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return JsonReader().read(s)
added
removed
tools/scripts/json.py
