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, stream = sys.stdout):
  64         self.stream = stream
  65         self.level = 0;
  66
  67     def _write(self, s):
  68         self.stream.write(s)
  69
  70     def _indent(self):
  71         self._write('  '*self.level)
  72
  73     def _newline(self):
  74         self._write('\n')
  75
  76     def visit_object(self, node):
  77         self.enter_object()
  78
  79         members = node.keys()
  80         members.sort()
  81         for i in range(len(members)):
  82             name = members[i]
  83             value = node[name]
  84             self.enter_member(name)
  85             self.visit(value)
  86             if i:
  87                 self._write(',')
  88             self.leave_member()
  89         self.leave_object()
  90
  91     def enter_object(self):
  92         self._write('{')
  93         self._newline()
  94         self.level += 1
  95
  96     def enter_member(self, name):
  97         self._indent()
  98         self._write('%s: ' % name)
  99
 100     def leave_member(self):
 101         self._newline()
 102
 103     def leave_object(self):
 104         self.level -= 1
 105         self._indent()
 106         self._write('}')
 107
 108     def visit_array(self, node):
 109         self.enter_array()
 110         for i in range(len(node)):
 111             value = node[i]
 112             self._indent()
 113             self.visit(value)
 114             if i:
 115                 self._write(',')
 116             self._newline()
 117         self.leave_array()
 118
 119     def enter_array(self):
 120         self._write('[')
 121         self._newline()
 122         self.level += 1
 123
 124     def leave_array(self):
 125         self.level -= 1
 126         self._indent()
 127         self._write(']')
 128
 129     def visit_value(self, node):
 130         self._write(repr(node))
 131
 132
 133
 134 class Comparer(Visitor):
 135
 136     def visit_object(self, a, b):
 137         if not isinstance(b, dict):
 138             return False
 139         if len(a) != len(b):
 140             return False
 141         ak = a.keys()
 142         bk = b.keys()
 143         ak.sort()
 144         bk.sort()
 145         if ak != bk:
 146             return False
 147         for k in ak:
 148             if not self.visit(a[k], b[k]):
 149                 return False
 150         return True
 151
 152     def visit_array(self, a, b):
 153         if not isinstance(b, list):
 154             return False
 155         if len(a) != len(b):
 156             return False
 157         for ae, be in zip(a, b):
 158             if not self.visit(ae, be):
 159                 return False
 160         return True
 161
 162     def visit_value(self, a, b):
 163         return a == b
 164
 165 comparer = Comparer()
 166
 167
 168 class Differ(Visitor):
 169
 170     def __init__(self, stream = sys.stdout):
 171         self.dumper = Dumper(stream)
 172
 173     def visit(self, a, b):
 174         if comparer.visit(a, b):
 175             return
 176         Visitor.visit(self, a, b)
 177
 178     def visit_object(self, a, b):
 179         if not isinstance(b, dict):
 180             self.replace(a, b)
 181         else:
 182             self.dumper.enter_object()
 183             names = set(a.keys())
 184             names.update(b.keys())
 185             names = list(names)
 186             names.sort()
 187
 188             for name in names:
 189                 ae = a.get(name, None)
 190                 be = b.get(name, None)
 191                 if not comparer.visit(ae, be):
 192                     self.dumper.enter_member(name)
 193                     self.visit(ae, be)
 194                     self.dumper.leave_member()
 195
 196             self.dumper.leave_object()
 197
 198     def visit_array(self, a, b):
 199         if not isinstance(b, list):
 200             self.replace(a, b)
 201         else:
 202             self.dumper.enter_array()
 203             for i in range(max(len(a), len(b))):
 204                 try:
 205                     ae = a[i]
 206                 except IndexError:
 207                     ae = None
 208                 try:
 209                     be = b[i]
 210                 except IndexError:
 211                     be = None
 212                 self.dumper._indent()
 213                 if comparer.visit(ae, be):
 214                     self.dumper.visit(ae)
 215                 else:
 216                     self.visit(ae, be)
 217                 self.dumper._newline()
 218
 219             self.dumper.leave_array()
 220
 221     def visit_value(self, a, b):
 222         if a != b:
 223             self.replace(a, b)
 224
 225     def replace(self, a, b):
 226         self.dumper.visit(a)
 227         self.dumper._write(' -> ')
 228         self.dumper.visit(b)
 229
 230
 231 def load(stream):
 232     return json.load(stream, strict=False, object_hook = object_hook)
 233
 234
 235 def main():
 236     a = load(open(sys.argv[1], 'rt'))
 237     b = load(open(sys.argv[2], 'rt'))
 238
 239     #dumper = Dumper()
 240     #dumper.visit(a)
 241
 242     differ = Differ()
 243     differ.visit(a, b)
 244
 245
 246 if __name__ == '__main__':
 247     main()