JsonDiffPatch

This library is an implementation of a Json Patch RFC 6902.

• forked from https://github.com/tavis-software/Tavis.JsonPatch
• plus a modified diff generator by Ian Mercer (http://blog.abodit.com/2014/05/json-patch-c-implementation/)

The default example from the specification looks like this,

[
     { "op": "test", "path": "/a/b/c", "value": "foo" },
     { "op": "remove", "path": "/a/b/c" },
     { "op": "add", "path": "/a/b/c", "value": ["foo", "bar"] },
     { "op": "replace", "path": "/a/b/c", "value": 42 },
     { "op": "move", "from": "/a/b/c", "path": "/a/b/d" },
     { "op": "copy", "from": "/a/b/d", "path": "/a/b/e" }
]

This library allows you to create this document by doing,

var patchDoc = new PatchDocument( new Operation[]
    {
    	new TestOperation() {Path = new JsonPointer("/a/b/c"), Value = new JValue("foo")}, 
         	new RemoveOperation() {Path = new JsonPointer("/a/b/c") }, 
         	new AddOperation() {Path = new JsonPointer("/a/b/c"), Value = new JArray(new JValue("foo"), new JValue("bar"))}, 
         	new ReplaceOperation() {Path = new JsonPointer("/a/b/c"), Value = new JValue(42)}, 
         	new MoveOperation() {FromPath = new JsonPointer("/a/b/c"), Path = new JsonPointer("/a/b/d") }, 
    	new CopyOperation() {FromPath = new JsonPointer("/a/b/d"), Path = new JsonPointer("/a/b/e") }, 
    });

This document can be serialized to the wire format like this,

     var outputstream = patchDoc.ToStream();

You can also read patch documents from the wire representation and apply them to a JSON document.

var targetDoc = JToken.Parse("{ 'foo': 'bar'}");
    var patchDoc = PatchDocument.Parse(@"[ { 'op': 'add', 'path': '/baz', 'value': 'qux' } ]");

    patchDoc.ApplyTo(targetDoc);

You can also generate a patchdocument by diffing two json objects

	var left = JToken.Parse(leftString);
        	var right = JToken.Parse(rightString);
        	var patchDoc = new JsonDiffer().Diff(left, right);

You can apply a patch document to a json object too.

	var left = JToken.Parse(leftString);
        	var patcher = new JsonPatcher();
        	patcher.Patch(ref left, patchDoc); //left is now updated by the patchDoc

The unit tests provide examples of other usages.

This library is a PCL based library and so will work on Windows 8, Windows Phone 7.5, .Net 4.

A nuget package is available here.