在字符串上调用成员函数 addEagerConstraints() - Laravel 8

Question

I want to get response with type_name property, without adding new field in the table

{
  "status": 200,
  "message": "OK",
  "data": {
    "id": 23,
    "uuid": "9b1d33f9-0e44-4161-9936-ec41309697a5",
    "sender_id": null,
    "receiver_id": 2,
    "type": 0,
    "coin": 200,
    "balance": 27000,
    "description": "Topup 200 coin",
    "type_name": "Topup"
}

Therefore I tried to create a method named typeName() inside the CoinTransaction model, in the hope that the method can be called via with() method like that:

$transaction = CoinTransaction::create([
     'receiver_id'   => auth()->user()->id,
     'coin'          => $request->coin,
     'balance'       => $predefineCoin->balance ?? 1000,
     'type'          => 0,
     'description'   => $request->description
]);

$transaction = CoinTransaction::with(['typeName'])->find($transaction->id);

But it's return an error:

Error: Call to a member function addEagerConstraints() on string...

In my CoinTransaction model

class CoinTransaction extends Model
{
    use HasFactory;

    protected $guarded  = ['id'];


    public function sender() {
        return $this->belongsTo(User::class, 'sender_id');
    }


    public function receiver() {
        return $this->belongsTo(User::class, 'receiver_id');
    }


    public function typeName() {
        $typeName = null;

        switch($this->type){
            case 0: $typeName = 'Topup'; break;
            default: $typeName = 'Unknown';
        }

        return $typeName;
    }
}

Answer 1

typeName is not relationship method so you have typeName() like below

$coin=CoinTransaction::find($transaction->id); 
dd($coin->typeName());

or

To add type_name attribute to existing response ,you can use Mutators

Ref : https://laravel.com/docs/8.x/eloquent-mutators#accessors-and-mutators

So add below property and method in CoinTransaction

protected $appends = ['type_name'];

and method

public function getTypeNameAttribute()
{
    $typeName = null;

        switch($this->type){
            case 0: $typeName = 'Topup'; break;
            default: $typeName = 'Unknown';
        }

        return $typeName;    
}

so in controller

$transaction = CoinTransaction::find($transaction->id);