CGI Usage

As visible in this wiki's home, the CGI usage is pretty simple, here how to print a "Hello World!" phrase in the browser:

$mf = require_once('crystal.php');

$mf('/', function () {
    echo 'Hello World!';
});

second argument must be callable, so you can use

$mf('/', function () { /* ... */ });
$mf('/', 'function');
$mf('/', array($object, 'method'));
$mf('/', array('Class', 'staticMethod'));
$mf('/', 'Class::staticMethod');
$mf('/', $object); // Used with __invoke

HTTP request methods are the third parameter and are controlled using a regular expression.

$mf('/', function () {
    echo 'Hello ' . $_POST['name'] . '!';
}, 'POST');

$mf('/', function () {
    echo 'Hello ' . $_SERVER['REQUEST_METHOD'] . '!';
}, 'GET|POST');

Routes are defined using a regular expression too.

$mf('/hello/world', function () {
    echo 'Hello ';
});
$mf('/hello(.*)', function () {
    echo 'World!';
});
// Output: Hello World!

Use named subpatterns to define parameters order.

$mf('/(?P<user>[^\/]+)/(?P<verb>[^\/]+)', function ($verb, $user) {
    echo 'Output: ' . $verb . ' ' . $user . '!';
});

// http://localhost/bob/hello
// Output: hello bob!

Attention: don't forget to configure your webserver!

Priorities

Priority is used to set callbacks order, each function is called using highest priority 0 but you can set it passing a not negative integer or a not negative float number.

// $mf('/', function () { echo 'A'; });
$mf('/', function () { echo 'A'; }, 'GET', 0);
$mf('/', function () { echo 'B'; }, 'GET', 1);

// Output: AB

$mf('/', function () { echo 'A'; }, 'GET', 1);
$mf('/', function () { echo 'B'; }, 'GET', 0);

// Output: BA

In command line usage priority is the second parameter.

To break callbacks chain use the exit() function.

Page not found

The HTTP 404 error is defined as a regular expression too and is matched if no one of currently defined regular expressions match current URL. To retrieve the 404 regular expression call the function with the argument router:not-found (available only if not in CLI mode).

$mf('/', function () {
    echo 'Hello World!';
});

$mf($mf('router:not-found'), function () {
    echo 'Error 404: Page not Found';
});

This is part of the microframework Utilities.