add options parameter

README.md

@@ -104,6 +104,8 @@ When your application has changed the state of this object, the `sync` method of
 
 The [diffsync-todos app](https://github.com/janmonschke/diffsync-todos) provides an example client-side integration of diffsync into a todo list application. Check it out to find out how to integrate it into your existing application. In a nutshell, it makes use of `Object.observe` (and a polyfill for it) to track changes from within the app that are then synced to the server.
 
+As a third optional parameter you can pass an options object to the constructor, that will then be applied to the internal diff-library. For a list of options, please check <https://github.com/benjamine/jsondiffpatch#options>.
+
 ### Server
 
 Setting up the server in a very minimal way (with express):
@@ -130,6 +132,8 @@ Setting up the server in a very minimal way (with express):
 
 This is all that is needed for running the server part. There is no further addition necessary. Most of the logic is happening in the `DataAdapter`, which is described in the next section.
 
+As a third optional parameter you can pass an options object to the constructor, that will then be applied to the internal diff-library. For a list of options, please check <https://github.com/benjamine/jsondiffpatch#options>.
+
 ### DataAdapter
 
 A `DataAdapter` is used by the server component internally to fetch data to initialize the synchronization and to save the data periodically. The simple interface allows to write a custom data provider for which ever data source you are using in your web app.

src/client.js

@@ -1,17 +1,17 @@
-var isEmpty       = require('lodash.isempty'),
+var assign        = require('lodash.assign'),
     bind          = require('lodash.bind'),
+    isEmpty       = require('lodash.isempty'),
     EventEmitter  = require('events').EventEmitter,
-    jsondiffpatch = require('jsondiffpatch').create({
-      objectHash: function(obj) { return obj.id || obj._id || JSON.stringify(obj); }
-    }),
+    jsondiffpatch = require('jsondiffpatch'),
 
     COMMANDS  = require('./commands'),
     utils     = require('./utils'),
     Client;
 
-Client = function(socket, room){
+Client = function(socket, room, diffOptions){
   if(!socket){ throw new Error('No socket specified'); }
   if(!room){ room = ''; }
+  if(!diffOptions){ diffOptions = {}; }
 
   this.socket = socket;
   this.room = room;
@@ -26,6 +26,15 @@ Client = function(socket, room){
     edits: []
   };
 
+  // set up the jsondiffpatch options
+  // see here for options: https://github.com/benjamine/jsondiffpatch#options
+  diffOptions = assign({
+    objectHash: function(obj) { return obj.id || obj._id || JSON.stringify(obj); }
+  }, diffOptions);
+
+  this.jsondiffpatch = jsondiffpatch.create(diffOptions);
+
+  // let client be an EventEmitter
   EventEmitter.call(this);
 
   // bind functions
@@ -154,7 +163,7 @@ Client.prototype.syncWithServer = function(){
  * @return {Diff}      The diff of both documents
  */
 Client.prototype.createDiff = function(docA, docB){
-  return jsondiffpatch.diff(docA, docB);
+  return this.jsondiffpatch.diff(docA, docB);
 };
 
 /**
@@ -164,7 +173,7 @@ Client.prototype.createDiff = function(docA, docB){
  * @param  {Diff} patch
  */
 Client.prototype.applyPatchTo = function(obj, patch){
-  jsondiffpatch.patch(obj, patch);
+  this.jsondiffpatch.patch(obj, patch);
 };
 
 /**

src/server.js

@@ -1,15 +1,15 @@
-var isEmpty       = require('lodash.isempty'),
+var assign        = require('lodash.assign'),
     bind          = require('lodash.bind'),
-    jsondiffpatch = require('jsondiffpatch').create({
-      objectHash: function(obj) { return obj.id || obj._id || JSON.stringify(obj); }
-    }),
+    isEmpty       = require('lodash.isempty'),
+    jsondiffpatch = require('jsondiffpatch'),
 
     COMMANDS  = require('./commands'),
     utils     = require('./utils'),
     Server;
 
-Server = function(adapter, transport){
+Server = function(adapter, transport, diffOptions){
   if(!(adapter && transport)){ throw new Error('Need to specify an adapter and a transport'); }
+  if(!diffOptions){ diffOptions = {}; }
 
   this.adapter = adapter;
   this.transport = transport;
@@ -18,6 +18,14 @@ Server = function(adapter, transport){
   // bind functions
   this.trackConnection = bind(this.trackConnection, this);
 
+  // set up the jsondiffpatch options
+  // see here for options: https://github.com/benjamine/jsondiffpatch#options
+  diffOptions = assign({
+    objectHash: function(obj) { return obj.id || obj._id || JSON.stringify(obj); }
+  }, diffOptions);
+
+  this.jsondiffpatch = jsondiffpatch.create(diffOptions);
+
   this.transport.on('connection', this.trackConnection);
 };
 
@@ -124,12 +132,12 @@ Server.prototype.receiveEdit = function(connection, editMessage, sendToClient){
 
         // 3) patch the shadow
         // var snapshot = utils.deepCopy(clientDoc.shadow.doc);
-        jsondiffpatch.patch(clientDoc.shadow.doc, utils.deepCopy(edit.diff));
+        this.jsondiffpatch.patch(clientDoc.shadow.doc, utils.deepCopy(edit.diff));
         // clientDoc.shadow.doc = snapshot;
 
         // apply the patch to the server's document
         // snapshot = utils.deepCopy(doc.serverCopy);
-        jsondiffpatch.patch(doc.serverCopy, utils.deepCopy(edit.diff));
+        this.jsondiffpatch.patch(doc.serverCopy, utils.deepCopy(edit.diff));
         // doc.serverCopy = snapshot;
 
         // 3.a) increase the version number for the shadow if diff not empty
@@ -142,7 +150,7 @@ Server.prototype.receiveEdit = function(connection, editMessage, sendToClient){
         console.log('error', 'patch rejected!!', edit.serverVersion, '->', clientDoc.shadow.serverVersion, ':',
                     edit.localVersion, '->', clientDoc.shadow.localVersion);
       }
-    });
+    }.bind(this));
 
     // 4) save a snapshot of the document
     this.saveSnapshot(editMessage.room);
@@ -166,9 +174,7 @@ Server.prototype.saveSnapshot = function(room){
 
 Server.prototype.sendServerChanges = function(doc, clientDoc, send){
   // create a diff from the current server version to the client's shadow
-  // important: use deepcopied versions
-  // var diff = jsondiffpatch.diff(utils.deepCopy(clientDoc.shadow.doc), utils.deepCopy(doc.serverCopy));
-  var diff = jsondiffpatch.diff(clientDoc.shadow.doc, doc.serverCopy);
+  var diff = this.jsondiffpatch.diff(clientDoc.shadow.doc, doc.serverCopy);
   var basedOnServerVersion = clientDoc.shadow.serverVersion;
 
   // add the difference to the server's edit stack
@@ -182,7 +188,7 @@ Server.prototype.sendServerChanges = function(doc, clientDoc, send){
     clientDoc.shadow.serverVersion++;
 
     // apply the patch to the server shadow
-    jsondiffpatch.patch(clientDoc.shadow.doc, utils.deepCopy(diff));
+    this.jsondiffpatch.patch(clientDoc.shadow.doc, utils.deepCopy(diff));
   }
 
   // we explicitly want empty diffs to get sent as well

test/client_test.js

@@ -37,6 +37,12 @@ describe('DiffSync Client', function(){
       assert.notStrictEqual(testClient().room, null);
       assert.notStrictEqual(testClient().room, undefined);
     });
+
+    it('should apply the correct options to jsondiffpatch', function(){
+      var client = new Client({}, 1, { textDiff: { minLength: 2 }});
+
+      assert(client.jsondiffpatch.options().textDiff.minLength === 2);
+    });
   });
 
   describe('initialize', function(){

test/server_test.js

@@ -54,6 +54,12 @@ describe('DiffSync Server', function(){
         new Server(testAdapter(), testTransport());
       });
     });
+
+    it('should apply the correct options to jsondiffpatch', function(){
+      var client = new Server(testAdapter(), testTransport(), { textDiff: { minLength: 2 }});
+
+      assert(client.jsondiffpatch.options().textDiff.minLength === 2);
+    });
   });
 
   describe('trackConnection', function(){