git.cworth.org Git - apitrace/blob - scripts/jsondiff.py

   1 #!/usr/bin/env python
   2 ##########################################################################
   3 #
   4 # Copyright 2011 Jose Fonseca
   5 # All Rights Reserved.
   6 #
   7 # Permission is hereby granted, free of charge, to any person obtaining a copy
   8 # of this software and associated documentation files (the "Software"), to deal
   9 # in the Software without restriction, including without limitation the rights
  10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11 # copies of the Software, and to permit persons to whom the Software is
  12 # furnished to do so, subject to the following conditions:
  13 #
  14 # The above copyright notice and this permission notice shall be included in
  15 # all copies or substantial portions of the Software.
  16 #
  17 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23 # THE SOFTWARE.
  24 #
  25 ##########################################################################/
  26
  27
  28 import json
  29 import sys
  30
  31
  32 def object_hook(obj):
  33     if '__class__' in obj:
  34         return None
  35     for name in obj.keys():
  36         if name.startswith('__') and name.endswith('__'):
  37             del obj[name]
  38     return obj
  39
  40
  41 class Visitor:
  42
  43     def visit(self, node, *args, **kwargs):
  44         if isinstance(node, dict):
  45             return self.visit_object(node, *args, **kwargs)
  46         elif isinstance(node, list):
  47             return self.visit_array(node, *args, **kwargs)
  48         else:
  49             return self.visit_value(node, *args, **kwargs)
  50
  51     def visit_object(self, node, *args, **kwargs):
  52         pass
  53
  54     def visit_array(self, node, *args, **kwargs):
  55         pass
  56
  57     def visit_value(self, node, *args, **kwargs):
  58         pass
  59
  60
  61 class Dumper(Visitor):
  62
  63     def __init__(self):
  64         self.level = 0;
  65
  66     def _write(self, s):
  67         sys.stdout.write(s)
  68
  69     def _indent(self):
  70         self._write('  '*self.level)
  71
  72     def _newline(self):
  73         self._write('\n')
  74
  75     def visit_object(self, node):
  76         self.enter_object()
  77
  78         members = node.keys()
  79         members.sort()
  80         for i in range(len(members)):
  81             name = members[i]
  82             value = node[name]
  83             self.enter_member(name)
  84             self.visit(value)
  85             if i:
  86                 self._write(',')
  87             self.leave_member()
  88         self.leave_object()
  89
  90     def enter_object(self):
  91         self._write('{')
  92         self._newline()
  93         self.level += 1
  94
  95     def enter_member(self, name):
  96         self._indent()
  97         self._write('%s: ' % name)
  98
  99     def leave_member(self):
 100         self._newline()
 101
 102     def leave_object(self):
 103         self.level -= 1
 104         self._indent()
 105         self._write('}')
 106
 107     def visit_array(self, node):
 108         self.enter_array()
 109         for i in range(len(node)):
 110             value = node[i]
 111             self._indent()
 112             self.visit(value)
 113             if i:
 114                 self._write(',')
 115             self._newline()
 116         self.leave_array()
 117
 118     def enter_array(self):
 119         self._write('[')
 120         self._newline()
 121         self.level += 1
 122
 123     def leave_array(self):
 124         self.level -= 1
 125         self._indent()
 126         self._write(']')
 127
 128     def visit_value(self, node):
 129         self._write(repr(node))
 130
 131
 132
 133 class Comparer(Visitor):
 134
 135     def visit_object(self, a, b):
 136         if not isinstance(b, dict):
 137             return False
 138         if len(a) != len(b):
 139             return False
 140         ak = a.keys()
 141         bk = b.keys()
 142         ak.sort()
 143         bk.sort()
 144         if ak != bk:
 145             return False
 146         for k in ak:
 147             if not self.visit(a[k], b[k]):
 148                 return False
 149         return True
 150
 151     def visit_array(self, a, b):
 152         if not isinstance(b, list):
 153             return False
 154         if len(a) != len(b):
 155             return False
 156         for ae, be in zip(a, b):
 157             if not self.visit(ae, be):
 158                 return False
 159         return True
 160
 161     def visit_value(self, a, b):
 162         return a == b
 163
 164 comparer = Comparer()
 165
 166
 167 class Differ(Visitor):
 168
 169     def __init__(self):
 170         self.dumper = Dumper()
 171
 172     def visit(self, a, b):
 173         if comparer.visit(a, b):
 174             return
 175         Visitor.visit(self, a, b)
 176
 177     def visit_object(self, a, b):
 178         if not isinstance(b, dict):
 179             self.replace(a, b)
 180         else:
 181             self.dumper.enter_object()
 182             names = set(a.keys())
 183             names.update(b.keys())
 184             names = list(names)
 185             names.sort()
 186
 187             for name in names:
 188                 ae = a.get(name, None)
 189                 be = b.get(name, None)
 190                 if not comparer.visit(ae, be):
 191                     self.dumper.enter_member(name)
 192                     self.visit(ae, be)
 193                     self.dumper.leave_member()
 194
 195             self.dumper.leave_object()
 196
 197     def visit_array(self, a, b):
 198         if not isinstance(b, list):
 199             self.replace(a, b)
 200         else:
 201             self.dumper.enter_array()
 202             for i in range(max(len(a), len(b))):
 203                 try:
 204                     ae = a[i]
 205                 except KeyError:
 206                     ae = None
 207                 try:
 208                     be = b[i]
 209                 except KeyError:
 210                     be = None
 211                 self.dumper._indent()
 212                 if comparer.visit(ae, be):
 213                     self.dumper.visit(ae)
 214                 else:
 215                     self.visit(ae, be)
 216                 self.dumper._newline()
 217
 218             self.dumper.leave_array()
 219
 220     def visit_value(self, a, b):
 221         if a != b:
 222             self.replace(a, b)
 223
 224     def replace(self, a, b):
 225         self.dumper.visit(a)
 226         self.dumper._write(' -> ')
 227         self.dumper.visit(b)
 228
 229
 230 def load(filename):
 231     return json.load(open(filename, 'rt'), strict=False, object_hook = object_hook)
 232
 233
 234 def main():
 235     a = load(sys.argv[1])
 236     b = load(sys.argv[2])
 237
 238     #dumper = Dumper()
 239     #dumper.visit(a)
 240
 241     differ = Differ()
 242     differ.visit(a, b)
 243
 244
 245 if __name__ == '__main__':
 246     main()