How to get $_POST and $_GET parameters

Question

I call a route via AJAX and pass data to it. In a controller, I want to get $_POST['var'], but it does seem to work on Drupal 8.

How I can get values contained in $_POST from a controller?

Answer 1

From the change record:

$name = $_POST['name']; // form param

becomes

$name = \Drupal::request()->request->get('name'); // form param

Incidentally, for GET vars, you would use:

$query = \Drupal::request()->query->get('name');

Answer 2

In a controller get the request with a type-hinted argument Request $request:

<?php

namespace Drupal\mymodule\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\Request;

class ExampleController extends ControllerBase {

  /**
   * Controller to return a POST or a GET parameter.
   */
  public function action(Request $request) {

    // get your POST parameter
    $foo = $request->request->get('foo');

    // or get your GET parameter
    $foo = $request->query->get('foo');

    // POST requests are not cached, but for GET you need a cache context
    return [
      '#plain_text' => $foo,
      '#cache' => ['contexts' => ['url.query_args:foo']],
    ];
  }

}

More info https://www.drupal.org/docs/8/api/routing-system/using-parameters-in-routes

Use #plain_text to escape the input data for HTML output. See https://www.drupal.org/node/2559263

Answer 3

Inject the RequestStack into your controller.

The current request contains the query attribute that in turn contains the GET parameters. request contains the POST parameters.

<?php

namespace Drupal\example_module\Controller;

use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\HttpFoundation\RequestStack;
use Symfony\Component\DependencyInjection\ContainerInterface;

/**
 * An example controller.
 */
class ExampleController extends ControllerBase {

  /**
   * @var \Symfony\Component\HttpFoundation\RequestStack
   */
  private $requestStack;

  /**
   * Constructor.
   *
   * @param \Symfony\Component\HttpFoundation\RequestStack $request_stack
   */
  public function __construct(RequestStack $request_stack) {
    $this->requestStack = $request_stack;
  }

  /**
   * {@inheritdoc}
   */
  public static function create(ContainerInterface $container) {
    return new static(
      $container->get('request_stack')
    );
  }

  /**
   * {@inheritdoc}
   */
  public function action() {
    // Get your GET parameter here.
    $this->requestStack->getCurrentRequest()->query->get('foo');
  }

}

Answer 4

If you are using Content-Type: application/json please use :

$post_data = json_decode( $this->request->getContent(),TRUE);

Answer 5

You can check the Request object like

\Drupal::request()->getMethod();

it will returns GET or POST or whatever. If you are working inside an object, remember to DI the Request service.

Answer 6

None of the other answers worked for me but I found this that did:

$request->getContent();

Answer 7

This is an example for accessing URL parameters and passing them to a template. I am assuming you have already created your module and required files and that /test?fn=admin is the path your module is using.

In Your .module file implement hook_theme() and define variables and template name. (Make sure you replace _ with - when creating the template file.)

function my_module_theme () {   
  return [
    'your_template_name' => [
      'variables' => [
        'first_name'    => NULL,
      ],
    ],
  ];
}

Now create your controller and put the following code in it.

 namespace Drupal\my_module\Controller;
 
 use Drupal\Core\Controller\ControllerBase;
 use Symfony\Component\HttpFoundation\Request;

 class MyModule extends ControllerBase {
 
   public function content(Request $request) {
     return [
       '#theme' => 'my_template',
       '#first_name' => $request->query->get('fn'), //This is because the parameters are in $_GET, if you are accessing from $_POST then use "request" instead "query"
     ];
   }

 }

In template file, which should be my-template.html.twig, you can access this parameter as <h3>First Name: {{ first_name }}</h3>.