Get a collection and add a value to the response - node.js

Question

I want to create in the Server script a function that can return a collection plus some extra value.
For example:
Meteor.publish("users", function () {
var users;
users = Meteor.users.find();
users.forEach(function (user){
user.profile.image = "some-url";
});
return users;
});
But this don't work proper. My question is: What is the right way to add a value to a collection reponse in a publish function.

Answer 1

There are 2 ways you can implement a publish function:
By returning a cursor (or an array of cursors)
By using this.added(), this.changed() and this.removed().
Only method 2 allows to modify returned documents.
Please refer to Meteor documentation here. However, since the provided sample code might look complex, here is another one:
// server: publish the rooms collection
Meteor.publish("rooms", function () {
return Rooms.find({});
});
is equivalent to:
// server: publish the rooms collection
Meteor.publish("rooms", function () {
var self = this;
var handle = Rooms.find({}).observeChanges({
added: function(id, fields) { self.added("rooms", id, fields); },
changed: function(id, fields) { self.changed("rooms", id, fields); },
removed: function(id) { self.added("rooms", id); },
}
});
self.ready();
self.onStop(function () { handle.stop(); });
});
In the second sample, you can modify the 'field' parameter before sending it for publication, like this:
added: function(id, fields) {
fields.newField = 12;
self.added("rooms", id, fields);
},
Source: this post.

Answer 2

Is this important to do with the server? You could use the transform function on the client:
Client JS
//Somewhere where it can run before anything else (make sure you have access to the other bits of the document i.e services.facebook.id otherwise you'll get a services is undefined
Meteor.users._transform = function(doc) {
doc.profile.image = "http://graph.facebook.com/" + doc.services.facebook.id + "/picture";
return doc;
}
Now when you do:
Meteor.user().profile.image
=> "http://graph.facebook.com/55592/picture"
I have opened an issue before with regards to sharing a transform onto the client: https://github.com/meteor/meteor/issues/821