From 4e552ec514c28c6334603efa769a696b605b31f3 Mon Sep 17 00:00:00 2001
From: Nick Martin <nim@meteor.com>
Date: Thu, 16 Feb 2012 16:24:58 -0800
Subject: [PATCH 1/3] Don't send empty objects to the client.

---
 packages/livedata/livedata_server.js | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/packages/livedata/livedata_server.js b/packages/livedata/livedata_server.js
index 17f08da420..1f09974019 100644
--- a/packages/livedata/livedata_server.js
+++ b/packages/livedata/livedata_server.js
@@ -107,12 +107,17 @@ _.extend(Meteor._LivedataServer.prototype, {
         var msg = {msg: 'data', collection: collection_name, id: id};
 
         if (!old_obj) {
+          // New object. Send an insert down to the client.
           var obj_to_send = _.extend({}, new_obj);
           delete obj_to_send._id;
-          msg.set = obj_to_send;
-          socket.send(JSON.stringify(msg));
+          if (_.keys(obj_to_send).length) {
+            msg.set = obj_to_send;
+            socket.send(JSON.stringify(msg));
+          }
 
         } else {
+          // Old object. Check for updates and send changes attributes
+          // to the client.
           var set = {};
           var unset = [];
 

From c309647c0c240e07598d95453279565f063037b8 Mon Sep 17 00:00:00 2001
From: Nick Martin <nim@meteor.com>
Date: Thu, 16 Feb 2012 16:25:12 -0800
Subject: [PATCH 2/3] Warn on empty object insert.

---
 packages/livedata/livedata_client.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/packages/livedata/livedata_client.js b/packages/livedata/livedata_client.js
index e8c2aa6540..a0b2f88201 100644
--- a/packages/livedata/livedata_client.js
+++ b/packages/livedata/livedata_client.js
@@ -355,7 +355,10 @@ _.extend(Meteor._Collection.prototype, {
     // Generate an id for the object.
     // XXX mutates the object passed in. that is not cool.
     if (obj._id)
-      Meteor._debug("WARNING: trying to insert object w/ _id set");
+      Meteor._debug("WARNING: trying to insert object w/ _id set. _id ignored.");
+    if (_.keys(obj).length === 0)
+      Meteor._debug("WARNING: inserting empty object.");
+
     var _id = Collection.uuid();
     obj._id = _id;
 

From 1ce3f3b8125ad35183f5972fd3c88a2ef70cf156 Mon Sep 17 00:00:00 2001
From: Nick Martin <nim@meteor.com>
Date: Thu, 16 Feb 2012 17:50:54 -0800
Subject: [PATCH 3/3] Add note in docs re empty objects.

---
 docs/client/api.html | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/docs/client/api.html b/docs/client/api.html
index f511f17590..a242eed407 100644
--- a/docs/client/api.html
+++ b/docs/client/api.html
@@ -84,6 +84,15 @@ Meteor.publish("user-posts", {
 });
 </pre>
 
+<p>Publish acts on individual attributes of objects. If an object has no
+attributes except <code>_id</code>, it will not be published to the
+client.  Generally, empty object are not very useful so this is not a
+problem.  If you need to create and track an object and assign it
+properties later, create it with a simple property
+eg: <code>collection.insert({exists: true});</code>
+</p>
+
+
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