Laravel: Adding relationships to a pivot model

Question

How can I add a relationship to a pivot Model?

I have the following tables:

users
-id

events
-id

user_event
-id
-user_id
-event_id

tickets
-price
-user_event_id

So one User could visit many events and one Event belongs to many Users. Now I want that a User could have many different tickets for one special Event.

My models are the following:

Event:

class Event extends Eloquent{
    // Joins
    public function getUsers(){
        return $this->belongsToMany('User', 'user_event', 'event_id', 'user_id')->withPivot('id', 'emailSent', 'info')->withTimestamps();
    }
    // Pivot
    public function newPivot(Eloquent $parent, array $attributes, $table, $exists) {
       if ($parent instanceof User) {
            return new UserEvent($parent, $attributes, $table, $exists);
       }
       return parent::newPivot($parent, $attributes, $table, $exists);
    }

User:

class User extends Eloquent implements UserInterface, RemindableInterface {
    //Joins  
    public function getEvents(){
        return $this->belongsToMany('Event', 'user_event', 'user_id', 'event_id')->withPivot('id', 'emailSent', 'info')->withTimestamps();
    }


    // Pivot
    public function newPivot(Eloquent $parent, array $attributes, $table, $exists) {
        if ($parent instanceof Event) {
            return new UserEvent($parent, $attributes, $table, $exists);
        }
        return parent::newPivot($parent, $attributes, $table, $exists);
    }

UserEvent

use Illuminate\Database\Eloquent\Relations\Pivot;

class UserEvent extends Pivot{
    protected $table = 'user_event';
    public function tickets() {
        return $this->hasMany('Ticket'); 
    }
}

Ticket

class Ticket extends Eloquent{
    // Joins
    public function getUserEvent(){
        return $this->belongsTo('user_event','user_event_id');
    }

Now I want to list the first ticket for one specific User to one specific Event: I tried the following:

$event->first()->getUsers->first()->pivot->tickets->first();

But I get an error message:

Call to a member function first() on a non-object

I don't know where I should look to solve that problem. I've already looked to

• https://github.com/laravel/framework/issues/2093#issuecomment-39154456

• Using pivot model data as a relationship to another model in Laravel 4's Eloquent

but it didn't solved my problem.

Any ideas? Or isn't that possible with Eloquent?

Answer 1

The error you get is probably caused by some typo (->getUsers->first() part I suppose), because the code you pasted should throw DB error unknown column event_id when it reaches ->tickets part.

So first solve this issue, and then:

to make it work, you need to specify foreign key in the relation, because Eloquent guesses it using getForeignKey() which is overriden on the Pivot class and returns different value (event_id in this case):

class UserEvent extends Pivot{
    protected $table = 'user_event';
    public function tickets() {
        return $this->hasMany('Ticket', 'user_event_id'); 
    }
}