Retrieve user email given userId - meteor

Question

This is more or less a follow up to this question.
I am trying to display "friends", I have a list of friends I sent a request to (called sent):
{{#each sent}}
<p>{{find_user _id}}</p>
{{/each}}
Sent is generated like so:
Template.friends.sent = function () {
return Notifications.find({from: Meteor.userId(), // to, and from are now userIds and not the user like in the original question.
type: 'friendship'});
}
And a query for the count gives a number of seven. My find_user template is defined as such:
Template.friends.find_user = function (id) {
return Meteor.users.find({_id: id});
}
How can I get the email from the a user id? Doing something like:
{{(find_user _id).emails.[0].address}}
fails, with:
Expected IDENTIFIER.

Answer 1

So first it appears you are iterating over a cursor from a Notifications collection and then calling the find_user method on the template with the _id of a Notification record. You'll need to use the from field of the document as it's the field that contains the userId.
Next you'll want to at least rewrite your find_user method so that it doesn't take a parameter. You can access the same data from within the helper because this is set to the current data context.
Template.friends.find_user = function () {
return Meteor.users.find({_id: this.from}); //note the this.from
}
Then you should be able to access the email address with via your template helper as long as you are publishing that data for the current user.
{{from_user.emails.0.address}}
Personally I like to use Meteor's collection transforms to extend my models with prototypes that can be used just like template helpers.
//first we create our collection and add a transform option
Notifications = new Meteor.Collection("notifications", {
transform: function(document){
return new Notification(document);
}
});
//next we create our constructor
Notification = function(document){
_(this).extend(document);
};
//Then add some prototypal methods that we can use in our templates.
Notification.prototype = {
fromUser: function(){
return Meteor.users.findOne(this.from);
}
};
Now we can use this in our templates like this:
{{fromUser.emails.0.address}}
We can also take this one really great step farther by using the users _transform property to set a function that transforms user documents as well and then add methods to them as well.
//transform each user document into a new User instance
Meteor.users._transform = function(document){
return new User(document);
};
//User constructor
User = function(document){
_(this).extend(document);
};
//and finally the User prototype with methods
User.prototype = {
defaultEmail: function(){
return this.emails && this.emails[0].address;
}
};
Now as a final result you can use it like this:
{{#each sent}
<p>{{fromUser.defaultEmail}}</p>
{{/each}}