--- /dev/null
+#!/usr/bin/env python
+##########################################################################
+#
+# Copyright 2011 Jose Fonseca
+# All Rights Reserved.
+#
+# 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.
+#
+##########################################################################/
+
+
+import json
+import sys
+
+
+def object_hook(obj):
+ if '__class__' in obj:
+ return None
+ for name in obj.keys():
+ if name.startswith('__') and name.endswith('__'):
+ del obj[name]
+ return obj
+
+
+class Visitor:
+
+ def visit(self, node, *args, **kwargs):
+ if isinstance(node, dict):
+ return self.visit_object(node, *args, **kwargs)
+ elif isinstance(node, list):
+ return self.visit_array(node, *args, **kwargs)
+ else:
+ return self.visit_value(node, *args, **kwargs)
+
+ def visit_object(self, node, *args, **kwargs):
+ pass
+
+ def visit_array(self, node, *args, **kwargs):
+ pass
+
+ def visit_value(self, node, *args, **kwargs):
+ pass
+
+
+class Dumper(Visitor):
+
+ def __init__(self):
+ self.level = 0;
+
+ def _write(self, s):
+ sys.stdout.write(s)
+
+ def _indent(self):
+ self._write(' '*self.level)
+
+ def _newline(self):
+ self._write('\n')
+
+ def visit_object(self, node):
+ self.enter_object()
+
+ members = node.keys()
+ members.sort()
+ for i in range(len(members)):
+ name = members[i]
+ value = node[name]
+ self.enter_member(name)
+ self.visit(value)
+ if i:
+ self._write(',')
+ self.leave_member()
+ self.leave_object()
+
+ def enter_object(self):
+ self._write('{')
+ self._newline()
+ self.level += 1
+
+ def enter_member(self, name):
+ self._indent()
+ self._write('%s: ' % name)
+
+ def leave_member(self):
+ self._newline()
+
+ def leave_object(self):
+ self.level -= 1
+ self._indent()
+ self._write('}')
+
+ def visit_array(self, node):
+ self.enter_array()
+ for i in range(len(node)):
+ value = node[i]
+ self._indent()
+ self.visit(value)
+ if i:
+ self._write(',')
+ self._newline()
+ self.leave_array()
+
+ def enter_array(self):
+ self._write('[')
+ self._newline()
+ self.level += 1
+
+ def leave_array(self):
+ self.level -= 1
+ self._indent()
+ self._write(']')
+
+ def visit_value(self, node):
+ self._write(repr(node))
+
+
+
+class Comparer(Visitor):
+
+ def visit_object(self, a, b):
+ if not isinstance(b, dict):
+ return False
+ if len(a) != len(b):
+ return False
+ ak = a.keys()
+ bk = b.keys()
+ ak.sort()
+ bk.sort()
+ if ak != bk:
+ return False
+ for k in ak:
+ if not self.visit(a[k], b[k]):
+ return False
+ return True
+
+ def visit_array(self, a, b):
+ if not isinstance(b, list):
+ return False
+ if len(a) != len(b):
+ return False
+ for ae, be in zip(a, b):
+ if not self.visit(ae, be):
+ return False
+ return True
+
+ def visit_value(self, a, b):
+ return a == b
+
+comparer = Comparer()
+
+
+class Differ(Visitor):
+
+ def __init__(self):
+ self.dumper = Dumper()
+
+ def visit(self, a, b):
+ if comparer.visit(a, b):
+ return
+ Visitor.visit(self, a, b)
+
+ def visit_object(self, a, b):
+ if not isinstance(b, dict):
+ self.replace(a, b)
+ else:
+ self.dumper.enter_object()
+ names = set(a.keys())
+ names.update(b.keys())
+ names = list(names)
+ names.sort()
+
+ for name in names:
+ ae = a.get(name, None)
+ be = b.get(name, None)
+ if not comparer.visit(ae, be):
+ self.dumper.enter_member(name)
+ self.visit(ae, be)
+ self.dumper.leave_member()
+
+ self.dumper.leave_object()
+
+ def visit_array(self, a, b):
+ if not isinstance(b, list):
+ self.replace(a, b)
+ else:
+ self.dumper.enter_array()
+ for i in range(max(len(a), len(b))):
+ try:
+ ae = a[i]
+ except KeyError:
+ ae = None
+ try:
+ be = b[i]
+ except KeyError:
+ be = None
+ self.dumper._indent()
+ if comparer.visit(ae, be):
+ self.dumper.visit(ae)
+ else:
+ self.visit(ae, be)
+ self.dumper._newline()
+
+ self.dumper.leave_array()
+
+ def visit_value(self, a, b):
+ if a != b:
+ self.replace(a, b)
+
+ def replace(self, a, b):
+ self.dumper.visit(a)
+ self.dumper._write(' -> ')
+ self.dumper.visit(b)
+
+
+def load(filename):
+ return json.load(open(filename, 'rt'), strict=False, object_hook = object_hook)
+
+
+def main():
+ a = load(sys.argv[1])
+ b = load(sys.argv[2])
+
+ #dumper = Dumper()
+ #dumper.visit(a)
+
+ differ = Differ()
+ differ.visit(a, b)
+
+
+if __name__ == '__main__':
+ main()