Run PHP built-in web server with no need of a router file.

php-server

#!/usr/bin/env php
<?php
/**
 * Usage: php-server [ OPTIONS ] [ DOCUMENT_ROOT ]
 *
 * When not defined, DOCUMENT_ROOT is the current directory.
 *
 *   -a, --application   Defines the application file (default "index.php")
 *   -b, --background    When defined runs server in background
 *   -h, --host          Defines the host of the HTTP web server (default "127.0.0.1")
 *   -p, --port          Defines the port of the HTTP web server (default "8888")
 *
 * Report bugs to Henrique Moody <henriquemoody@gmail.com>.
 */

set_exception_handler(function (Exception $exception) {
    fwrite(STDERR, $exception->getMessage().PHP_EOL);
    if (count($exception->getTrace()) > 1) {
        fwrite(STDERR, $exception->getTraceAsString().PHP_EOL);
    }
    exit($exception->getCode() ?: 254);
});

$applicationFile = 'index.php';
$background = false;
$host = '127.0.0.1';
$port = 8888;
$workingDirectory = getcwd();

$arguments = $_SERVER['argv'];
array_shift($arguments);
while (($argument = array_shift($arguments))) {
    if (in_array($argument, ['-b', '--background'])) {
        $background = true;
        continue;
    }

    if (in_array($argument, ['-a', '--application'])) {
        $applicationFile = array_shift($arguments);
        continue;
    }

    if (in_array($argument, ['-p', '--port'])) {
        $port = array_shift($arguments);
        continue;
    }

    if (in_array($argument, ['-h', '--host'])) {
        $host = array_shift($arguments);
        continue;
    }

    $workingDirectory = $argument;
}

if (!is_dir($workingDirectory)) {
    throw new UnexpectedValueException(sprintf('"%s" is not a valid directory', $workingDirectory));
}

$basename = 'php-server_'.$host.'-'.$port;
$stdin  = ['pipe', 'r'];
if (false === $background) {
    $stdout = fopen('php://stdout', 'w');
    $stderr = fopen('php://stderr', 'w');
} else {
    $stdout = fopen('/tmp/'.$basename.'.log', 'w');
    $stderr = $stdout;
}

$routerFilename = '/tmp/'.$basename.'.php';
$routerFormat = <<<'EOF'
<?php
$uri = $_SERVER['REQUEST_URI'];
$directory = '%s';
if (is_file($directory.'/'.$uri)) {
    return false;
}
include $directory.'/%s';
EOF;
file_put_contents($routerFilename, sprintf($routerFormat.PHP_EOL, realpath($workingDirectory), $applicationFile));

$command = sprintf('%s -S %s:%d %s', PHP_BINARY, $host, $port, $routerFilename);
$process = proc_open(
    $command,
    [0 => $stdin, 1 => $stdout, 2 => $stderr],
    $pipes,
    $workingDirectory,
    $_ENV
);

if (true === $background) {
    posix_setsid();
    exit(0);
}

$pid = proc_get_status($process)['pid'];
while (0 === pcntl_waitpid($pid, $status, WNOHANG | WUNTRACED)) {
    sleep(2);
}

fwrite($stderr, 'HTTP server has stopped working'.PHP_EOL);
fclose($process);