Send checkpoints' id to the server to avoid storing duplicates

www/common/outer/chainpad-netflux-worker.js

@@ -68,7 +68,7 @@ define([], function () {
 
         // shim between chainpad and netflux
         var msgIn = function (peerId, msg) {
-            return msg.replace(/^cp\|/, '');
+            return msg.replace(/^cp\|([A-Za-z0-9+\/=]+\|)?/, '');
         };
 
         var msgOut = function (msg) {

www/common/sframe-app-framework.js

@@ -443,7 +443,7 @@ define([
                 patchTransformer: options.patchTransformer || ChainPad.SmartJSONTransformer,
 
                 // cryptpad debug logging (default is 1)
-                // logLevel: 2,
+                logLevel: 2,
                 validateContent: options.validateContent || function (content) {
                     try {
                         JSON.parse(content);

www/common/sframe-chainpad-netflux-outer.js

@@ -53,7 +53,16 @@ define([], function () {
             if (readOnly) { return; }
             try {
                 var cmsg = Crypto.encrypt(msg);
-                if (msg.indexOf('[4') === 0) { cmsg = 'cp|' + cmsg; }
+                if (msg.indexOf('[4') === 0) {
+                    var id = '';
+                    if (window.nacl) {
+                        var hash = window.nacl.hash(window.nacl.util.decodeUTF8(msg));
+                        id = window.nacl.util.encodeBase64(hash.slice(0, 8)) + '|';
+                    } else {
+                        console.log("Checkpoint sent without an ID. Nacl is missing.");
+                    }
+                    cmsg = 'cp|' + id + cmsg;
+                }
                 return cmsg;
             } catch (err) {
                 console.log(msg);