Testing your API with PHPUnit

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Testing your API with PHPUnit

What, a testing chapter so early? Yep, with API’s, you really can’t avoid it, and that’s a good thing. One way or another, to develop, test and debug each endpoint, you’ll need to either write some code or configure an HTTP browser plugin like Postman. And if you’re already doing all that work, you might as well make these calls repeatable and automated.

Guzzle and PHPUnit

Like I mentioned, if you’re making HTTP requests in PHP, you’ll want to use Guzzle, like we are in our testing.php file. So, the easiest way to create tests is just to put PHPUnit and Guzzle together.

I already have PHPUnit installed in our app via Composer, so let’s go straight to writing a test. Create a new Tests directory and put a ProgrammerControllerTest.php file there. Create a class inside and extend the normal PHPUnit base class:

// src/KnpU/CodeBattle/Tests/ProgrammerControllerTest.php
namespace KnpU\CodeBattle\Tests;

class ProgrammerControllerTest extends \PHPUnit_Framework_TestCase


Next, add a testPOST method and copy in the POST logic from the testing.php script:

// src/KnpU/CodeBattle/Tests/ProgrammerControllerTest.php
// ...

public function testPOST()
    // create our http client (Guzzle)
    $client = new Client('http://localhost:8000', array(
        'request.options' => array(
            'exceptions' => false,

    $nickname = 'ObjectOrienter'.rand(0, 999);
    $data = array(
        'nickname' => $nickname,
        'avatarNumber' => 5,
        'tagLine' => 'a test dev!'

    $request = $client->post('/api/programmers', null, json_encode($data));
    $response = $request->send();

Finally, let’s add some asserts to check that the status code is 201, that we have a Location header and that we get back valid JSON:

// src/KnpU/CodeBattle/Tests/ProgrammerControllerTest.php
// ...

public function testPOST()
    // ...

    $request = $client->post('/api/programmers', null, json_encode($data));
    $response = $request->send();

    $this->assertEquals(201, $response->getStatusCode());
    $data = json_decode($response->getBody(true), true);
    $this->assertArrayHasKey('nickname', $data);

To try it out, use the vendor/bin/phpunit executable and point it at the test file.

$ php vendor/bin/phpunit src/KnpU/CodeBattle/Tests/ProgrammerControllerTest.php

With any luck, Sebastian Bergmann will tell you that everything is ok! Of course I never trust a test that passes on the first try, so be sure to change things and make sure it fails when it should too.

Leave a comment!

This tutorial uses a deprecated micro-framework called Silex. The fundamentals of REST are still 💯valid, but the code we use can't be used in a real application.

What PHP libraries does this tutorial use?

// composer.json
    "require": {
        "silex/silex": "~1.0", // v1.3.2
        "symfony/twig-bridge": "~2.1", // v2.7.3
        "symfony/security": "~2.4", // v2.7.3
        "doctrine/dbal": "^2.5.4", // v2.5.4
        "monolog/monolog": "~1.7.0", // 1.7.0
        "symfony/validator": "~2.4", // v2.7.3
        "symfony/expression-language": "~2.4" // v2.7.3
    "require-dev": {
        "behat/mink": "~1.5", // v1.5.0
        "behat/mink-goutte-driver": "~1.0.9", // v1.0.9
        "behat/mink-selenium2-driver": "~1.1.1", // v1.1.1
        "behat/behat": "~2.5", // v2.5.5
        "behat/mink-extension": "~1.2.0", // v1.2.0
        "phpunit/phpunit": "~5.7.0", // 5.7.27
        "guzzle/guzzle": "~3.7" // v3.9.3