How to test HTTP Server with PHPUnit

[razonyang]

Hi, I want to test the HTTP server with PHPUnit in coroutine, but I couldn't access the server within test case.

1. RazonYang\Psr7\Swoole\Tests\EmitterFactoryTest::testEmit
   Symfony\Component\HttpClient\Exception\TimeoutException: Idle timeout reached for "http://127.0.0.1:9555/".

<?php

use Swoole\Coroutine\Http\Server;
use Swoole\Http\Request;
use Swoole\Http\Response;

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

go(function() {
    $srv = new Server('0.0.0.0', 9555);

    $srv->handle('/', function(Request $request, Response $response) {
        $response->end('OK');
    });

    printf("server starting.\n");
    $srv->start();
});

go(function() {
    sleep(5);
    printf("unit test.\n");
    global $argc, $argv;
    try {
        require __DIR__ . '/vendor/bin/phpunit';
    } catch (\Swoole\ExitException $e) {
        return;
    }
});

What's the correct way to test HTTP server with PHPUnit?

I was able to start an external Swoole HTTP server(different process via exec), all looks good except the code coverage, any code used in that server won't be covered.

Related question: #4831.