MySQL hasOne relation to Mongo

[tdicks]

I've never played with MongoDB before but this is really getting me into it. I'm using MySQL to store basic picture data such as filename, filesize etc, and MongoDB to store metadata which might be different for each picture (exif, ifd0) etc.

I've successfully got the MongoDB model set up and saving:

   $user = User::whereUsername('test_username')->first();
   $img = new Image();
   $img->filename = "hello.jpg";
   $img->save();

   $meta = new ImageMeta();
   $meta->exif_maker = "Canon";
   $meta->exif_model = "EOS 500D";
   $meta->save();

   $img->meta()->save($meta);

However when I try to get the metadata back from the image:

   echo $img->meta->exif_maker;

It returns NULL. Am I doing something wrong? If I look at the ImageMeta MongoDB model, I can see an image_id key which is populated with the image_id of the Image model.

Image relation:

$this->hasOne('ImageMeta');

ImageMeta relation:

$this->belongsTo('Image');

Image model table schema:

        Schema::create('images', function(Blueprint $table)
        {
            $table->increments('id');
            $table->string('filename');
            $table->integer('filesize');
            $table->string('hash');
            $table->string('hash_type');
            $table->integer('user_id');
            $table->timestamps();
        });

Any ideas?

[jenssegers]

Can you check out: https://github.com/jenssegers/Laravel-MongoDB/blob/master/tests/RelationsTest.php#L105

It seems to be working for me, or am I missing anything?

[tdicks]

I think the difference is I'm using MySQL for the Image and User models, and MongoDB for the ImageMeta model. Would that cause any problems?

[jenssegers]

I think so, because $img->meta() will return an SQL relation, and not a MongoDB relation.

[tdicks]

Ah right, I was expecting it to return a generic relation which is independent of the databases used. If that's not the case, I expect I can work around it. Or alternatively just not use MySQL and have MongoDB as my main database for everything.

Thanks for your help, much obliged.

[jenssegers]

Sorry for my delayed response.

[amacgregor]

Is there any way to get this working( A relation between a Mongo Model and a MySql Model) ?

[programming-kid]

yes this would be awesome using best of both mysql and mongo with same interface would be amazing

[jenssegers]

They are using the same "interface", but not the same objects. If you define a belongsTo or any other relation on an original sql model object, it will return a mysql relation. And if you define a relation on a mongodb model, it will return a modified object, specific for mongodb.

[ollieread]

I'm using both MongoDB and MySQL in my application, and I thought about this issue too. Couldn't you check the connection type? So if we're trying to use a MySQL model as a relationship, wait until after the initial query then get it separately? The fact that the child is a MySQL object should make it easy there on to modify.

[jenssegers]

@ollieread, then it would only work in 1 direction, from a mongo-model to original model. But not the other way around.

[ollieread]

@jenssegers I see what you're saying but that would at least solve half the problem, perhaps a second model for Eloquent models, that overrides the relationship handler if the requested object extends your Model? I imagine it'd be relatively simple, I'd be happy to take a look myself?

[jenssegers]

Sure, go ahead :)

[ollieread]

Changes

• Jenssegers\Mongodb\Model will now return MySQL relations if the Model in question is an instance of Illuminate\Database\Eloquent\Model
• Added Jenssegers\Mongodb\CrossModel so that MySQL models can have MongoDB relations and MySQL relations.

I tested quite a bit on my end, but if somebody else would like to test, then please do so.

I have the tests viewable here: http://laravel.ollieread.com/mongo