"""
@author Thomas Lehmann
@file easyjson.py
Copyright (c) 2013 Thomas Lehmann
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies
or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""
def tokenize(buffer):
""" tokenizes a JSON string """
tokens = []
maxIndex = len(buffer)-1
index = 0
while index <= maxIndex:
if buffer[index] in ["{", "}", ":", ",", "[", "]"]:
tokens.append(buffer[index])
index += 1
elif buffer[index] in ".1234567890":
current = index + 1
while current <= maxIndex and buffer[current] in ".1234567890":
current += 1
token = buffer[index:current]
if token.find(".") >= 0: tokens.append(float(token))
else: tokens.append(int(token))
index = current
elif buffer[index] == "\"":
current = index+1
while current <= maxIndex and (buffer[current-1] == "\\" or buffer[current] != "\""):
current += 1
tokens.append(buffer[index+1:current].replace("\\",""))
index = current+1
elif index+4 <= maxIndex and buffer[index:index+4] == "true":
tokens.append(True)
index += 4
elif index+5 <= maxIndex and buffer[index:index+5] == "false":
tokens.append(False)
index += 5
elif index+4 <= maxIndex and buffer[index:index+4] == "null":
tokens.append(None)
index += 4
else:
index += 1
return tokens
def parse(tokens, object):
""" does the parse of the scanned/tokenized JSON string
@param tokens list of JSON tokens
@param object final dictionary or one 'node' in the tree while parsing """
name = None
array = None
while len(tokens) > 0:
token = tokens.pop()
if token == "{":
if array == None:
if not name == None:
object[name] = object.__class__()
parse(tokens, object[name])
name = None
else:
subObject = object.__class__()
array.append(parse(tokens, subObject))
elif token == "}":
return object
elif token == "[":
array = []
elif token == "]":
assert not name == None
object[name] = array
array = None
name = None
elif token in [':', ',']:
pass
elif token in [True, False, None]:
if array == None:
assert not name == None
object[name] = token
else:
array.append(token)
elif type(token) in [type(0), type(0.0)]:
if array == None:
assert not name == None
object[name] = token
else:
array.append(token)
elif type(token) == type(""):
if array == None:
if not name == None:
object[name] = token
name = None
else:
name = token
else:
array.append(token)
return object
def loadFromBuffer(buffer, dictionary = None):
if not dictionary: dictionary = {}
return parse(list(reversed(tokenize(buffer))), dictionary)
def loadFromFile(pathAndFileName, dictionary = None):
if not dictionary: dictionary = {}
return loadFromBuffer(open(pathAndFileName).read(), dictionary)
def test():
def assertEqual(a, b):
if not a == b:
print("assertion has failed:\n expected: '%s'\n given: '%s'" % (a, b))
assert False
# Testing the tokenize function:
# ==============================
# one (name, value) pair
expected = ["{", "firstName", ":", "Thomas", "}"]
assertEqual(expected, tokenize(""" { "firstName": "Thomas" } """))
# two (name, value) pairs
expected = ["{", "firstName", ":", "Thomas", ",", "surName", ":", "Lehmann", "}"]
assertEqual(expected , tokenize(""" { "firstName": "Thomas", "surName": "Lehmann" } """))
# one pair with a name and a list of integers
expected = [ "{", "squares", ":", "[", 1, ",", 2, ",", 4, ",", 8, ",", 12, "]", "}" ]
assertEqual(expected, tokenize(""" { "squares": [1, 2, 4, 8, 12] } """))
# one pair with a name and a boolean true
expected = [ "{", "isTrue", ":", True, "}" ]
assertEqual(expected, tokenize(""" { "isTrue": true } """))
# one pair with a name and a boolean false
expected = [ "{", "isTrue", ":", False, "}" ]
assertEqual(expected, tokenize(""" { "isTrue": false } """))
# one pair with a name and null value
expected = [ "{", "value", ":", None, "}" ]
assertEqual(expected, tokenize(""" { "value": null} """))
# one pair with a name and an object as value
expected = ['{', 'object', ':', '{', 'id', ':', 4711, '}', '}']
assertEqual(expected, tokenize(""" { "object" : { "id": 4711 } } """))
# one pair with a name and a strign value (string in string)
expected = ['{', 'object', ':', 'abc "def" xyz', '}']
assertEqual(expected, tokenize(""" { "object": "abc \\"def\\" xyz" } """))
# Testing the loadFromBuffer function:
# ====================================
# one (name, value) pair
expected = {'firstName': 'Thomas'}
assertEqual(expected, loadFromBuffer(""" { "firstName": "Thomas" } """))
# two (name, value) pairs
expected = {'firstName': 'Thomas', 'surName': 'Lehmann'}
assertEqual(expected, loadFromBuffer(""" { "firstName": "Thomas", "surName": "Lehmann" } """))
# one pair with a name and a list of integers
expected = {'squares': [1, 2, 4, 8, 12]}
assertEqual(expected, loadFromBuffer(""" { "squares": [1, 2, 4, 8, 12] } """))
# one pair with a name and a boolean true
expected = {'isTrue': True}
assertEqual(expected, loadFromBuffer(""" { "isTrue": true } """))
# one pair with a name and a boolean false
expected = {'isTrue': False}
assertEqual(expected, loadFromBuffer(""" { "isTrue": false } """))
# one pair with a name and a null value
expected = {'value': None}
assertEqual(expected, loadFromBuffer(""" { "value": null } """))
# one pair with a name and an object as value
expected = {'object': {'id': 4711}}
assertEqual(expected, loadFromBuffer(""" { "object" : { "id": 4711 } } """))
# one pair with a name and a list of objects
expected = {'parent': [{'child-one': 1}, {'child-two': 2}]}
assertEqual(expected, loadFromBuffer("""{ "parent" : [ { "child-one": 1 }, { "child-two": 2 } ] } """))
class MyDict:
def __init__(self): self.data = {}
def __setitem__(self, key, value): self.data[key] = value
def __getitem__(self, key): return self.data[key]
def __repr__(self): return "MyDict%s" % self.data
expected = """MyDict{'object': MyDict{'value': 3.5}}"""
assertEqual(expected, "%s" % loadFromBuffer(""" { "object" : { "value": 3.5 } } """, MyDict()))
if __name__ == "__main__":
test()
Diff to Previous Revision
--- revision 3 2013-05-27 05:30:50
+++ revision 4 2013-05-27 05:32:07
@@ -33,7 +33,9 @@
current = index + 1
while current <= maxIndex and buffer[current] in ".1234567890":
current += 1
- tokens.append(buffer[index:current])
+ token = buffer[index:current]
+ if token.find(".") >= 0: tokens.append(float(token))
+ else: tokens.append(int(token))
index = current
elif buffer[index] == "\"":
current = index+1
@@ -89,6 +91,12 @@
object[name] = token
else:
array.append(token)
+ elif type(token) in [type(0), type(0.0)]:
+ if array == None:
+ assert not name == None
+ object[name] = token
+ else:
+ array.append(token)
elif type(token) == type(""):
if array == None:
if not name == None:
@@ -124,7 +132,7 @@
expected = ["{", "firstName", ":", "Thomas", ",", "surName", ":", "Lehmann", "}"]
assertEqual(expected , tokenize(""" { "firstName": "Thomas", "surName": "Lehmann" } """))
# one pair with a name and a list of integers
- expected = [ "{", "squares", ":", "[", "1", ",", "2", ",", "4", ",", "8", ",", "12", "]", "}" ]
+ expected = [ "{", "squares", ":", "[", 1, ",", 2, ",", 4, ",", 8, ",", 12, "]", "}" ]
assertEqual(expected, tokenize(""" { "squares": [1, 2, 4, 8, 12] } """))
# one pair with a name and a boolean true
expected = [ "{", "isTrue", ":", True, "}" ]
@@ -136,7 +144,7 @@
expected = [ "{", "value", ":", None, "}" ]
assertEqual(expected, tokenize(""" { "value": null} """))
# one pair with a name and an object as value
- expected = ['{', 'object', ':', '{', 'id', ':', '4711', '}', '}']
+ expected = ['{', 'object', ':', '{', 'id', ':', 4711, '}', '}']
assertEqual(expected, tokenize(""" { "object" : { "id": 4711 } } """))
# one pair with a name and a strign value (string in string)
expected = ['{', 'object', ':', 'abc "def" xyz', '}']
@@ -151,7 +159,7 @@
expected = {'firstName': 'Thomas', 'surName': 'Lehmann'}
assertEqual(expected, loadFromBuffer(""" { "firstName": "Thomas", "surName": "Lehmann" } """))
# one pair with a name and a list of integers
- expected = {'squares': ['1', '2', '4', '8', '12']}
+ expected = {'squares': [1, 2, 4, 8, 12]}
assertEqual(expected, loadFromBuffer(""" { "squares": [1, 2, 4, 8, 12] } """))
# one pair with a name and a boolean true
expected = {'isTrue': True}
@@ -163,10 +171,10 @@
expected = {'value': None}
assertEqual(expected, loadFromBuffer(""" { "value": null } """))
# one pair with a name and an object as value
- expected = {'object': {'id': '4711'}}
+ expected = {'object': {'id': 4711}}
assertEqual(expected, loadFromBuffer(""" { "object" : { "id": 4711 } } """))
# one pair with a name and a list of objects
- expected = {'parent': [{'child-one': '1'}, {'child-two': '2'}]}
+ expected = {'parent': [{'child-one': 1}, {'child-two': 2}]}
assertEqual(expected, loadFromBuffer("""{ "parent" : [ { "child-one": 1 }, { "child-two": 2 } ] } """))
class MyDict:
@@ -175,8 +183,8 @@
def __getitem__(self, key): return self.data[key]
def __repr__(self): return "MyDict%s" % self.data
- expected = """MyDict{'object': MyDict{'id': '4711'}}"""
- assertEqual(expected, "%s" % loadFromBuffer(""" { "object" : { "id": 4711 } } """, MyDict()))
+ expected = """MyDict{'object': MyDict{'value': 3.5}}"""
+ assertEqual(expected, "%s" % loadFromBuffer(""" { "object" : { "value": 3.5 } } """, MyDict()))
if __name__ == "__main__":
test()
