Merge pull request #1358 from mluto/clientvars-hook

Make the creation of clientVars hookable

doc/api/hooks_server-side.md

@@ -175,6 +175,27 @@ function handleMessage ( hook, context, callback ) {
 };
 ```
 
+## clientVars
+Called from: src/node/handler/PadMessageHandler.js
+
+Things in context:
+
+1. clientVars - the basic `clientVars` built by the core
+2. pad - the pad this session is about
+
+This hook will be called once a client connects and the `clientVars` are being sent. Plugins can use this hook to give the client a initial configuriation, like the tracking-id of an external analytics-tool that is used on the client-side. You can also overwrite values from the original `clientVars`.
+
+Example:
+
+```
+exports.clientVars = function(hook, context, callback)
+{
+  // tell the client which year we are in
+  return callback({ "currentYear": new Date().getFullYear() });
+};
+```
+
+This can be accessed on the client-side using `clientVars.currentYear`.
 
 ## getLineHTMLForExport
 Called from: src/node/utils/ExportHtml.js

src/node/handler/PadMessageHandler.js

@@ -991,6 +991,15 @@ function handleClientReady(client, message)
       //Saves in pad2sessions that this session belongs to this pad
       pad2sessions[padIds.padId].push(client.id);
             
+      //If this is a reconnect, we don't have to send the client the ClientVars again
+      if(message.reconnect == true)
+      {
+        //Save the revision in sessioninfos, we take the revision from the info the client send to us
+        sessioninfos[client.id].rev = message.client_rev;
+      }
+      //This is a normal first connect
+      else
+      {
         //prepare all values for the wire
         var atext = Changeset.cloneAText(pad.atext);
         var attribsForWire = Changeset.prepareForWire(atext.attribs, pad.pool);
@@ -1012,7 +1021,6 @@ function handleClientReady(client, message)
           "collab_client_vars": {
               "initialAttributedText": atext,
               "clientIp": "127.0.0.1",
-            //"clientAgent": "Anonymous Agent",
               "padId": message.padId,
               "historicalAuthorData": historicalAuthorData,
               "apool": apool,
@@ -1055,19 +1063,22 @@ function handleClientReady(client, message)
           clientVars.userName = authorName;
         }
         
-      //If this is a reconnect, we don't have to send the client the ClientVars again
+        //call the clientVars-hook so plugins can modify them before they get sent to the client
-      if(message.reconnect == true)
+        hooks.aCallAll("clientVars", { clientVars: clientVars, pad: pad }, function ( err, messages ) {
-      {
+          if(ERR(err, callback)) return;
-        //Save the revision in sessioninfos, we take the revision from the info the client send to us
+          
-        sessioninfos[client.id].rev = message.client_rev;
+          _.each(messages, function(newVars) {
+            //combine our old object with the new attributes from the hook
+            for(var attr in newVars) {
+              clientVars[attr] = newVars[attr];
             }
-      //This is a normal first connect
+          });
-      else
+        
-      {
           //Send the clientVars to the Client
           client.json.send({type: "CLIENT_VARS", data: clientVars});
           //Save the current revision in sessioninfos, should be the same as in clientVars
           sessioninfos[client.id].rev = pad.getHeadRevisionNumber();
+        });
       }
         
       sessioninfos[client.id].author = author;