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laravellaravel-4eloquent

How to access model hasMany Relation with where condition?


I created a model Game using a condition / constraint for a relation as follows:

class Game extends Eloquent {
    // many more stuff here

    // relation without any constraints ...works fine 
    public function videos() {
        return $this->hasMany('Video');
    }

    // results in a "problem", se examples below
    public function available_videos() {
        return $this->hasMany('Video')->where('available','=', 1);
    }
}

When using it somehow like this:

$game = Game::with('available_videos')->find(1);
$game->available_videos->count();

everything works fine, as roles is the resulting collection.

MY PROBLEM:

when I try to access it without eager loading

$game = Game::find(1);
$game->available_videos->count();

an Exception is thrown as it says "Call to a member function count() on a non-object".

Using

$game = Game::find(1);
$game->load('available_videos');
$game->available_videos->count();

works fine, but it seems quite complicated to me, as I do not need to load related models, if I do not use conditions within my relation.

Have I missed something? How can I ensure, that available_videos are accessible without using eager loading?

For anyone interested, I have also posted this issue on http://forums.laravel.io/viewtopic.php?id=10470


Solution

  • Just in case anyone else encounters the same problems.

    Note, that relations are required to be camelcase. So in my case available_videos() should have been availableVideos().

    You can easily find out investigating the Laravel source:

    // Illuminate\Database\Eloquent\Model.php
    ...
    /**
     * Get an attribute from the model.
     *
     * @param  string  $key
     * @return mixed
     */
    public function getAttribute($key)
    {
        $inAttributes = array_key_exists($key, $this->attributes);
    
        // If the key references an attribute, we can just go ahead and return the
        // plain attribute value from the model. This allows every attribute to
        // be dynamically accessed through the _get method without accessors.
        if ($inAttributes || $this->hasGetMutator($key))
        {
            return $this->getAttributeValue($key);
        }
    
        // If the key already exists in the relationships array, it just means the
        // relationship has already been loaded, so we'll just return it out of
        // here because there is no need to query within the relations twice.
        if (array_key_exists($key, $this->relations))
        {
            return $this->relations[$key];
        }
    
        // If the "attribute" exists as a method on the model, we will just assume
        // it is a relationship and will load and return results from the query
        // and hydrate the relationship's value on the "relationships" array.
        $camelKey = camel_case($key);
    
        if (method_exists($this, $camelKey))
        {
            return $this->getRelationshipFromMethod($key, $camelKey);
        }
    }
    

    This also explains why my code worked, whenever I loaded the data using the load() method before.

    Anyway, my example works perfectly okay now, and $model->availableVideos always returns a Collection.