What is Body Parsing Middleware in Slim Framework?

Slim Framework - Interview Questions

It’s very common in web APIs to send data in JSON or XML format. Out of the box, PSR-7 implementations do not support these formats, you have to decode the Request object’s getBody() yourself. As this is a common requirement, Slim 4 provides BodyParsingMiddleware to handle this task.

It’s recommended to put the body parsing middleware before the call to addErrorMiddlware, so that the stack looks like this :

<?php

use Slim\Factory\AppFactory;

require_once __DIR__ . '/../vendor/autoload.php';

$app = AppFactory::create();

// Parse json, form data and xml
$app->addBodyParsingMiddleware();

$app->addRoutingMiddleware();

$app->addErrorMiddleware(true, true, true);

// ...

$app->run();

Posted JSON, form or XML data :

No changes are required to the POST handler because the BodyParsingMiddleware detects that the Content-Type is set to a JSON media type and so places the decoded body into the Request’s parsed body property.

For data posted to the website from a browser, you can use the $request’s getParsedBody() method.

This will return an array of the posted data.

$app->post('/', function (Request $request, Response $response, $args): Response {

    $data = $request->getParsedBody();

    

    $html = var_export($data, true);

    $response->getBody()->write($html);

    

    return $response;

});