Call to a member function setContentType() on null - Responsetrait

[davodm]

Hi, I had a similar problem as described in the forum, but I didn't see any fix yet, so I decided to post the bug here for fixing in the future.
https://forum.codeigniter.com/thread-77516.html

The bug occurred on response API with this error:
Call to a member function setContentType() on null - on line 114 Responsetrait.php

Its also fixed as it described in the topic:
public function respond($data = null, int $status = null, string $message = '') { $this->response=service('response');

• Web server Apache 2.4.46
• PHP version 7.4

[paulbalandan]

How are you using the ResponseTrait in your code? Can you give a sample?

[paulbalandan]

A class using a trait should be responsible for ensuring that the properties used by the trait is available when the trait will be using it. It is not the responsibility of trait to reinitialize a property that is of the class. Pending sample code, I see this as an implementation mistake on user's code.

[iRedds]

Upgrade the framework to version 4.0.5 if you are using php 7.2, or to version 4.1.1 if you are using php >= 7.3

The response property of the controller is defined in the initialization method.
If it is null, then you have changed the initialization method.

[davodm]

I'm currently using CI 4.1.1 & PHP 7.4 as I mentioned before.
Here is my usage:

public function error($status,$msg,$data){
   return $this->setResponseFormat('json')->respond([
      'status'=>$status,
      'msg'=>$msg,
      'data'=>$data
   ]);
}

And it's the error:

CRITICAL - 2021-04-06 18:33:24 --> Call to a member function setContentType() on null
#0 F:\xampp\htdocs\recovermsg\vendor\codeigniter4\framework\system\API\ResponseTrait.php(114): App\Libraries\Api->format(Array)
#1 F:\xampp\htdocs\recovermsg\app\Libraries\Api.php(28): App\Libraries\Api->respond(Array)
#2 F:\xampp\htdocs\recovermsg\app\Controllers\ApiV1\Log.php(29): App\Libraries\Api->success('Activity succes...')
#3 F:\xampp\htdocs\recovermsg\vendor\codeigniter4\framework\system\CodeIgniter.php(936): App\Controllers\ApiV1\Log->index()
#4 F:\xampp\htdocs\recovermsg\vendor\codeigniter4\framework\system\CodeIgniter.php(432): CodeIgniter\CodeIgniter->runController(Object(App\Controllers\ApiV1\Log))
#5 F:\xampp\htdocs\recovermsg\vendor\codeigniter4\framework\system\CodeIgniter.php(333): CodeIgniter\CodeIgniter->handleRequest(NULL, Object(Config\Cache), false)
#6 F:\xampp\htdocs\recovermsg\public\index.php(45): CodeIgniter\CodeIgniter->run()
#7 {main}

Unfortunately, I don't get the initialization method solution. I'm just using "use ResponseTrait;" like the document.

[iRedds]

ResponseTrait is used in controllers.
If you use it elsewhere, you must initialize the required components yourself.

[davodm]

Aha, got it, May I ask you to tell me how to initialize the required components in a Library?

[paulbalandan]

If you are using the trait in the context of a library, you should be initializing the response in the constructor.

use Config\Services;
use CodeIgniter\API\ResponseTrait;

class MyLibrary
{
    use ResponseTrait;

    protected $response;

    public function __construct()
    {
        $this->response = Services::response();
    }

    // other code
}

[paulbalandan]

Closing as not a bug.

[suwidadi]

Sorry to jump in the old thread. I believe this correlates with the error I experienced when I put ResponseTrait on a constructor. is it "illegal" if I put in a constructor? because this will output the setcontenttype() on null also.

use CodeIgniter\API\ResponseTrait;
use CodeIgniter\RESTful\ResourceController;

class Product extends ResourceController
{
    use ResponseTrait;
    
    public function __construct()
    {
        return $this->respond(["status"=>TRUE,"message"=>"Passed"],200);
    } 

    public function index()
    {
        echo 'blablabla';
    }
}

[kenjis]

It is illegal. It won't work.

1. You cannot use return in __construct. Constructor always returns a new instance of the class.
2. $this->respond() uses $this->response inside, but $this->response is not set in the __construct() yet.
   It will be set in initController().