Doctrine2 subquery in template - equivalent of symfony1 lazy query getter - symfony

Question

I have two tables:
comment - id, application_id, comment, user_id, created_at, deleted_at
comment_likes - comment_id, user_id
I can retrieve the comments for an application using the standard DQLSELECT u FROM Comment WHERE :application = application
When lopping through the comments, I want to see if the logged in user has already liked a comment.
In symfony1, I would have used a simple lazy query $comment->hasUserLiked()
At the moment, in symfony2, I have to do a query of all the user likes for an application comments and a query of all the application comments.
When looping through application comments I do a sub-loop in each comment to check whether that a user likes record exists in the user likes comments collection. This is not clean.
Hope this makes sense.
Is there a better way?
EDIT: I could use a sub-controller to render whether a user likes the comment or not....but that seems rather over the top just for a couple of lines of html. Although, cleaner than the current implementation.

Answer 1

You need to set up a bidirectional one-to-many relationship between the Comment and Comment\Like entities. This way, a Comment entity would know about all the likes it has. Then you could implement a method in it like $comment->hasBeenLikedBy($user) which would loop through all the likes it has and see if any of them was done by the user you passed.
The Comment entity:
<?php
namespace Model;
class Comment
{
/**
* #OneToMany(targetEntity="Model\Comment\Like", mappedBy="comment")
*/
private $likes;
public function hasBeenLikedBy(User $user)
{
foreach ($this->likes as $like) {
if ($like->getUser() == $user) {
return true;
}
return false;
}
}
}
The Comment\Like entity:
<?php
namespace Model\Comment;
class Like
{
/**
* #ManyToOne(targetEntity="Model\Comment")
*/
private $comment;
/**
* #ManyToOne(targetEntity="Model\User")
*/
private $user
public function getUser()
{
return $this->user;
}
}
This code is not complete and may contain mistakes, but I hope it's enough to show you the overall approach.

Answer 2

You can write your own hasUserLiked() function to query the database when called
You could join the comments and likes table and get the likes in the same call.
You can use the following query if your doctrine schema is setup correctly:
SELECT c FROM Comment c
LEFT JOIN c.CommentLikes cl
WHERE c.application = :application