Testing Zend Expressive 2 with kahlan 3

Zend\Expressive ^2.0 has different default approach for piping and routing middleware which is programmatically way. In this post, I am going to show you how you can test Zend\Expressive ^2.0 application, with assumption, you use its skeleton with kahlan 3.

First, of course, install the Expressive ^2.0 skeleton, for example, install into directory named “expressive2”:

$ composer create-project zendframework/zend-expressive-skeleton:^2.0 expressive2
Installing zendframework/zend-expressive-skeleton (2.0.0)
  - Installing zendframework/zend-expressive-skeleton (2.0.0) Downloading: 100%
Created project in expressive2
> ExpressiveInstaller\OptionalPackages::install
Setting up optional packages
Setup data and cache dir
Removing installer development dependencies

  What type of installation would you like?
  [1] Minimal (no default middleware, templates, or assets; configuration only)
  [2] Flat (flat source code structure; default selection)
  [3] Modular (modular source code structure; recommended)
  Make your selection (2): 3

Now, install kahlan:

$ cd expressive2
$ composer require kahlan/kahlan:^3.1

We are going to need the $app variable inside tests, for example, when testing functionality for each routed middlewares. To simplify and avoid repetitive code, we can register it into kahlan-config.php in root application:

// ./kahlan-config.php
use Kahlan\Filter\Filter;
use Zend\Expressive\Application;

Filter::register('initialize app', function($chain) {

    $root = $this->suite();

    ob_start();

    $root->beforeAll(function ($var) {

        ob_start();

        $var->app = $app
                  = (require 'config/container.php')->get(Application::class);

        require 'config/pipeline.php';
        require 'config/routes.php';

    });

    return $chain->next();

});
Filter::apply($this, 'run', 'initialize app');

By assign $app into “$var->app” like above, the “$app” is accessible from entire tests via “$this->app”, so, we can write test like the following:

// ./src/App/spec/Action/HomePageActionSpec.php
namespace AppSpec\Action;

use Zend\Diactoros\ServerRequest;

describe('HomePageAction', function () {

    describe('/', function () {

        it('contains welcome message', function () {

            $serverRequest = new ServerRequest([], [], '/', 'GET');
            $this->app->run($serverRequest);
            $actual = ob_get_clean();

            expect($actual)->toContain('Welcome to <span class="zf-green">zend-expressive</span>');

        });

    });

});

Now, let’s run the tests:

$ vendor/bin/kahlan --spec=src/App/spec/
            _     _
  /\ /\__ _| |__ | | __ _ _ __
 / //_/ _` | '_ \| |/ _` | '_ \
/ __ \ (_| | | | | | (_| | | | |
\/  \/\__,_|_| |_|_|\__,_|_| | |

The PHP Test Framework for Freedom, Truth and Justice.

Working Directory: /Users/samsonasik/www/expressive2

.                                                                   1 / 1 (100%)



Expectations   : 1 Executed
Specifications : 0 Pending, 0 Excluded, 0 Skipped

Passed 1 of 1 PASS in 0.375 seconds (using 8Mo)

That’s it 😉