I'm building a system for loaning out things like camera's, lights, etc.

I'm using laravel 9.7.0 with php 8.1.2 and a mySQL database on a remote server.

I've got three models:

item_instance.php

class Item_instance extends Model
{
    use HasFactory;

    public function item()
    {
        return $this->belongsTo(Item::class);
    }

    /**
     * @var array<string>
     */
    protected $fillable = [
        'damage',
        'notes',
        'status',
        'loan_id'
    ];

    public function loan()
    {
        return $this->belongsTo(Loan::class);
    }
}

User.php

class User extends Authenticatable
{
    use HasApiTokens, HasFactory, Notifiable;

    /**
     * The attributes that are mass assignable.
     *
     * @var array<int, string>
     */
    protected $fillable = [
        'name',
        'email',
        'password',
        'role'
    ];

    /**
     * The attributes that should be hidden for serialization.
     *
     * @var array<int, string>
     */
    protected $hidden = [
        'password',
        'remember_token',
    ];

    /**
     * The attributes that should be cast.
     *
     * @var array<string, string>
     */
    protected $casts = [
        'email_verified_at' => 'datetime',
    ];

    public function loan()
    {
        return $this->belongsTo(Loan::class);
    }
}

Loan.php

class Loan extends Model
{
    use HasFactory;

    public function user()
    {
        return $this->hasOne(User::class);
    }

    public function item_instances()
    {
        return $this->hasMany(Item_instance::class);
    }
}

In my migrations I defined the foreignId's like such:

loans:
$table->foreignId('user_id')->nullable()->references('id')->on('users')->onDelete('cascade');
$table->foreignId('item_instance_id')->nullable()->references('id')->on('item_instances')->onDelete('cascade');

users:
$table->integer('loan_id')->nullable()->references('id')->on('loans')->onDelete('cascade');

item_instances:
$table->foreignId('loan_id')->nullable()->references('id')->on('items')->onDelete('cascade');

In my seeder I generate 1 User and a couple item_instances. After this i try to insert a loan to check if everything is working:

        $loan = new Loan();
        $loan->save();

        $user = User::find(1);
        $i1 = Item_instance::find(1);
        $loan->item_instances()->save($i1);
        $loan->user()->save($user);

In both the user and the item_instance the loan_id is filled in. But the item_instance_id and the user_id for the loan entry remain NULL.

What am I doing wrong? I've bin trying different things for about 3 hours and can't seem to get it working.

Thanks!

CodePudding user response：

Your loans table is a pivot table that establishes a many-to-many relationship between Users and Item Instances.

You need fix up you relations.

App\Models\User.php:

public function item_instances() {
   // loans is the pivot table. you can also use Loan::class, since you've already created the class.
   return $this->belongsToMany(Item_instance::class, 'loans', 'user_id', 'item_instance_id');
}


App\Models\Item_instance.php:

public function user() {
   return $this->belongsToMany(User::class, 'loans', 'item_instance_id', 'user_id');
}

In your seeder:

$user = User::find(1);
$user->item_instances()->sync([1]); // 1 is the id of item instance you want to attach to this user instance (or id)

// you can also fill additional column in the pivot table like this (not required in your case):
$user->item_instances()->sync([1 => ['extra_column_in_lonas_table' => 'foo']]);

CodePudding user response：

You haven't defined $fillable property for Loan Model, Define $fillable property first