Relationships in models

Question

Relationships in models

Khaledzcom May '15

Created May '15	Last Reply May '15	Replies 6	Views 705	Votes 0

Khaledzcom 6.5k

May '15

Hello, I'm trying to get the advantages of the relationships in Phalcon models. I have two tables which is post and like.

each post has many likes while one like belongs to one post.

here is my models.

Like.php

<?php

namespace FC\Models;

use Phalcon\Mvc\Model\Validator\Email as EmailValidator;
use Phalcon\Mvc\Model\Validator\Uniqueness as UniquenessValidator;
use Phalcon\Mvc\Model;

class Like extends Model
{
    public $id;

    public $postID;

    public $userID;

    public function initialize()
    {
        $this->belongsTo("post_id", "post", "id");
    }
}

Post.php

<?php

namespace FC\Models;

use Phalcon\Mvc\Model\Validator\Email as EmailValidator;
use Phalcon\Mvc\Model\Validator\Uniqueness as UniquenessValidator;
use Phalcon\Mvc\Model;

class Post extends Model
{   
    public $id;

    public $content;

    public $created_at;

    public $likes;

    public $userID;

    public function initialize()
    {
        $this->hasMany("id", "Like", "post_id");
    }
}

UserController.php

<?php

namespace FC\Controllers;

use Phalcon\Mvc\Controller,
    FC\Controllers\ErrorController as Error,
    FC\Models\User,
    FC\Models\Post,
    FC\Models\User_follow,
    FC\Models\Like,
    FC\Models\User_info;

class UserController extends ControllerBase
{
    public function usernameAction($username)
    {
       $user_posts = Post::findFirst();
        foreach($user_posts->likes as $like)
        {
            var_dump($like);
        }
    }
}

It shows me this error: Warning: Invalid argument supplied for foreach().

Please correct me :) thanks.

Calin Rada · Answer 1 · 2015-05-20T04:24:59-07:00

Your structure look fine.

Do you have any records ? If yes, switch to point 2 if no, insert some data first.
Try this:

class Post extends Model 
{
    public function initialize()
    {
        $this->hasMany("id", "Like", "post_id", ['alias' => 'likes']);
    }

    // You can also have a getter if you need to execute some logic or complex code:

    public function getLikes($params = null)
    {
        return $this->getRelated('likes', $params);
    }
}

Khaledzcom · Answer 2 · 2015-05-20T05:39:26-07:00

Yes there is some records for both tables. I have updated my post model as in your reply.

now, it shows me empty page.

<?php

$this->view->disable();
$user_posts = Post::findFirst();

foreach($user_posts->getLikes() as $like)
{
    var_dump($like);
}

$user_posts = Post::findFirst(); shows me one record. but $user_posts->getLikes() is empty

Óscar Enríquez · Answer 3 · 2015-05-20T05:48:03-07:00

Yes there is some records for both tables. I have updated my post model as in your reply.

now, it shows me empty page.
<?php

$this->view->disable();
$user_posts = Post::findFirst();

foreach($user_posts->getLikes() as $like)
{
  var_dump($like);
}
$user_posts = Post::findFirst(); shows me one record. but $user_posts->getLikes() is empty

This is because dumping big objects with a lot of references inside uses a lot of memory, try var_dump($like->toArray()) or use XDebug, Symfony VarDumper etc

Khaledzcom · Answer 4 · 2015-05-20T05:57:44-07:00

Same result. here is my database:

Like table:

CREATE TABLE IF NOT EXISTS `like` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `postID` int(11) NOT NULL,
  `userID` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `postID` (`postID`),
  KEY `userID` (`userID`),
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=5 ;

--
-- Dumping data for table `like`
--

INSERT INTO `like` (`id`, `postID`, `userID`) VALUES
(1, 1, 1),
(2, 2, 1),
(3, 3, 2),
(4, 4, 3);

Post table

CREATE TABLE IF NOT EXISTS `post` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `content` text NOT NULL,
  `created_at` datetime NOT NULL,
  `userID` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `userID` (`userID`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=6 ;

--
-- Dumping data for table `post`
--

INSERT INTO `post` (`id`, `content`, `created_at`, `userID`) VALUES
(1, 'Hello World!', '2015-05-11 07:39:51', 1),
(2, 'Hi', '2015-05-11 07:43:32', 2),
(3, 'a new post\r\n', '2015-05-20 12:00:37', 1),
(4, 'Test', '2015-05-20 13:08:18', 3),
(5, 'ANother post', '2015-05-20 14:42:35', 1);

Constrains:

ALTER TABLE `like`
  ADD CONSTRAINT `like_ibfk_1` FOREIGN KEY (`postID`) REFERENCES `post` (`id`),
  ADD CONSTRAINT `like_ibfk_2` FOREIGN KEY (`userID`) REFERENCES `user` (`id`);

ALTER TABLE `post`
ADD CONSTRAINT `post_ibfk_1` FOREIGN KEY (`userID`) REFERENCES `user` (`id`);

I might missed something in my database

Calin Rada · Answer 5 · 2015-05-20T06:05:47-07:00

it seems ok. Strange.

try:

$this->hasMany("id", "Like", "post_id", [
    'alias' => 'likes',
    'foreignKey' => true
]);

Then

class UserController extends ControllerBase
{
    public function usernameAction($username)
    {
       $user_posts = Post::findFirst();
       var_dump($user_posts->count());
        foreach($user_posts->likes as $like)
        {
            var_dump( $like->id );
        }
    }
}

Khaledzcom · Answer 6 · 2015-05-20T06:19:13-07:00

here is the result:

string '5' (length=1) // the count result.

Warning: Invalid argument supplied for foreach()

post.php


<?php

class Post extends Model
{   
    public $id;

    public $content;

    public $created_at;

    public $likes;

    public $userID;

    public function initialize()
    {
        $this->hasMany("id", "Like", "post_id", [
            'alias' => 'likes',
            'foreignKey' => true
        ]);
    }
}

it seems the relationship not working. when I use getLikes() instead of likes it show empty result

Calin Rada · Answer 7 · 2015-05-20T06:27:15-07:00

Hm. If you declare the full namespace ?

    public function initialize()
    {
        $this->hasMany("id", "FC\Models\Like", "post_id", [
            'alias' => 'likes',
            'foreignKey' => true
        ]);
    }

Khaledzcom · Answer 8 · 2015-05-20T06:32:01-07:00

Khaledzcom
6.5k

May '15

I'm sorry to say it's same result :)

Calin Rada · Answer 9 · 2015-05-20T06:37:13-07:00

Your field name is postID not post_id .

    public function initialize()
    {
        $this->hasMany("id", "FC\Models\Like", "postID", [
            'alias' => 'likes',
            'foreignKey' => true
        ]);
    }

Khaledzcom · Answer 10 · 2015-05-20T06:39:12-07:00

Yes actually I changed that before I post in the fourm, and now I changed to postID but give me same result. I'm using Phalcon 2.0 and hope this is not bug in this version

Khaledzcom · Answer 11 · 2015-05-20T07:53:16-07:00

I set a relationships between user and post models and it works fine. I will try to figure out the problem between post and like :)

I will update this post once I solved :)

Khaledzcom · Answer 12 · 2015-05-20T20:21:17-07:00

Update:

if I use this code it shows me Fatal error: Call to undefined method Phalcon\Mvc\Model\Resultset\Simple::getLikes()


<?php
$post_likes = Post::find(['userID = 1']);
$likes = $post_likes->getLikes();

var_dump($likes->toArray()); return;

but if I changed to the following it works:


<?php
$post_likes = Post::findFirst();
$likes = $post_likes->getLikes();

var_dump($likes->toArray()); return;

What is the reason?

Calin Rada · Answer 13 · 2015-05-21T02:58:54-07:00

Post::find() is returning an instance of Phalcon\Mvc\Model\Resultset\Simple . That is an array of objects (Post object). You need to loop:

<?php
$posts= Post::find(['userID = 1']);

foreach ($posts as $post) {
    foreach ($post->getLikes() as $like) {
        var_dump($like->toArray());
    }
}

Or you can filter:

$posts_likes = Post::find(['userID = 1'])->filter(function($post){
    $likes = [];
    foreach ($post->getLikes() as $like) {
        $likes[] = $like->toArray();
    }

    return $likes;
});

var_dump($post_likes);

Khaledzcom · Answer 14 · 2015-05-22T03:46:31-07:00

Khaledzcom
6.5k

May '15

Thanks Calin Rada it works now. wish you all the best.