POST：来自 laravel 中 Messenger Bot 的 500 内部服务器错误

Question

I setup my Webhok by Ngrok URL for my Facebook page, and I applied all of the requirements for the Messenger Platform, but when I send the messages to my Facebook page I encounter the following error:

POST /Facebook_Messenger_Token 500 Internal Server Error 

and in routs file in Laravel I use Get and Post functions as follow:

Route::get('Facebook_Messenger_Token', 'MessengerController@index');
Route::post('Facebook_Messenger_Token', 'MessengerController@index');

When I send the messages I get the following error in storage/app.logs/laravel:

[2020-06-08 18:44:21] local.ERROR: Undefined variable: id {"exception":"[object] (ErrorException(code: 0): Undefined variable: id at C:\\xampp\\htdocs\\AzadApp\\app\\Http\\Controllers\\MessengerController.php:17)
[stacktrace]

my public function index:

public function index()
    {
        // here we can verify the webhook.
        // i create a method for that.
        $this->verifyAccess();

        $user    = json_decode($this->getUser($id)); --this is line 17
        $input   = json_decode(file_get_contents('php://input'), true);
        $id      = $input['entry'][0]['messaging'][0]['sender']['id'];
        $message = $input['entry'][0]['messaging'][0]['message']['text'];

        $response = [
            'recipient'     =>  ['id'   => $id ],
            'message'       =>  ['text' => "Thanks for watching {$user->first_name} {$user->last_name}! :)"]
        ];

        $this->sendMessage($response);
    }

Please support and thanks.

Answer 1

The $id is being defined on line 19 (that is after line 17). in order to use it on

$user = json_decode($this->getUser($id));

you should place the above line after line 19

$id = $input['entry'][0]['messaging'][0]['sender']['id'];

do not move line 19 up (as i said in my comment) instead move line 17 down since

$id = $input['entry'][0]['messaging'][0]['sender']['id'];

is using $input that is defined before.

all you have to do is move line 17 under line 19.

so the full function now should look like this:

public function index()
    {
        // here we can verify the webhook.
        // i create a method for that.
        $this->verifyAccess();


        $input   = json_decode(file_get_contents('php://input'), true);
        $id      = $input['entry'][0]['messaging'][0]['sender']['id'];
        $message = $input['entry'][0]['messaging'][0]['message']['text'];
        $user    = json_decode($this->getUser($id));

        $response = [
            'recipient'     =>  ['id'   => $id ],
            'message'       =>  ['text' => "Thanks for watching {$user->first_name} {$user->last_name}! :)"]
        ];

        $this->sendMessage($response);
    }