Arya is a minimalist PHP web SAPI framework providing URI routing, dependency injection and middleware hooks. The framework leverages HTTP protocol adherence and SOLID design principles to maximize flexibility while maintaining simplicity and performance.
WARNING: Arya is still under development and there is very little unit-testing present at the moment. The project is moving towards an official v0.1.0 release but has not yet reached that point. Code may change at any time and without warning. Use at your own risk.
<?php
$app = (new Arya\Application)
->before(function($request) {...}) // <-- middleware before request handled
->route('GET', '/', 'anyFunction')
->route('GET', '/lambda', $anyClosure)
->route('GET', '/static', 'AnyClass::staticMethod')
->route('GET', '/instance', 'AnyClass::instanceMethod') // <-- auto dependency injection
->route('GET', '/args/{arg1:\d+}/{arg2:\d+}', 'numericArgsFunction')
->after(function($request, $response) { ... }) // <-- middleware before response sent
->run()
;
- Model code on the HTTP/1.1 protocol as outlined in RFC 2616;
- Build components using SOLID, readable and well-tested code;
- Prevent vendor lock-in and static coupling;
- Minimize performance overhead.
You can clone the latest Arya iteration at anytime from the Github repository. By using the
--recursive
option git will automatically retrieve dependency submodules for us.
$ git clone --recursive git://github.com/rdlowrey/Arya.git
$ php composer.phar create-project rdlowrey/arya /path/to/later/location/Arya dev-master
Archived tagged release versions are also available (or will be) for manual download on the project tags page.
Arya acts as a front-controller to route all requests. To make this work you must configure your front-facing server to direct all requests to a single file.
With Apache 2.2.16 or higher, you can use the FallbackResource directive in your configuration file (.htaccess/httpd.conf/vhost.conf):
FallbackResource /front_controller.php
If you have an older version of Apache you should instead add this block to your config file:
<IfModule mod_rewrite.c>
Options -MultiViews
RewriteEngine On
RewriteBase /path/to/app
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^ front_controller.php [QSA,L]
</IfModule>
server {
...
index front_controller.php;
try_files $uri $uri/ /front_controller.php;
...
}
As of PHP 5.4 you can use the built-in development server to quickly run your application:
$ php -S localhost:8080 front_controller.php
Contributions in the form of pull requests (PRs) are always appreciated! Before submitting a PR please read the CONTRIBUTORS file.
Routing
Middleware
Dependency Injection
HTTP Protocol
Other
Server Setup
An Arya route definition consists of exactly three elements:
- HTTP method verb
- URI path
- Target callable
Arya supports any valid PHP callable as a route target. This means that you can specify function names, lambdas, static class methods and array instance method constructions. Consider:
<?php
$app = (new Arya\Application)
->route('GET', '/', 'myFunctionName')
->route('GET', '/lambda-hello', function() { return 'Hello world'; })
->route('POST', '/static-method', 'MyClass::myStaticPostHandler')
->route('GET', '/array-callback', [$myObject, 'someMethod'])
->route('GET', '/instance-method', 'MyController::get') // <-- IMPORTANT
->run()
;
Routes are matched in the order in which they are assigned with the caveat that routes without arguments always take precedence over routes with arguments (see (Route Arguments)[#route-arguments]).
You'll notice that in the above example code there's special attention paid to the final route,
SomeClass::someMethod
. We differentiate this route because it doesn't reference a static method.
How is this possible? Well ...
Arya recursively instantiates and provisions classes for you using the include Auryn
dependency
injection library. Consider the following simple example in which our MyController
class is
automatically instantiated and invoked for requests to the /
index resource:
<?php
class Templater {
function render($uri) {
return "<html><body><p>Hello from {$uri}!</p></body></html>";
}
}
class MyController {
private $templater;
function __construct(Templater $tpl) {
$this->templater = $tpl;
}
function get(Request $request) {
return $this->templater->render($request['REQUEST_URI']);
}
}
$app = (new Arya\Application)->route('GET', '/', 'MyController::get')->run();
IMPORTANT: Arya also recursively injects any dependencies you typehint in your controller method signatures. In the above example we use constructor injection to provide the
Templater
object that renders our HTML response. However, we could have alternatively typehinted theTemplater
in ourMyController::get
method signature and injected it at call time.
Arya uses FastRoute for routing.
/lol-cats/{catType}/{catId:\d+}
/widgets/{widgetId:\d+}
/kumqats/{kumqatId}
When named URI arguments are matched they are available to route targets in two different ways:
- As associative array keys in the
$request['ROUTE_ARGS']
array - As parameters with matching names in the route target's method/function signature
So, let's consider a match for our /lol-cats
route from above:
<?php
use Arya\Application;
function lolcatsFunction($request, $catType, $catId) {
assert($catType === $request['ROUTE_ARGS']['catType']);
assert($catId === $request['ROUTE_ARGS']['catId']);
return '<html><body>woot!</body></html>';
}
$app = (new Application)
->route('GET', '/lol-cats/$catType/$#catId', 'lolcatsFunction')
->run();
The takeaway here is that you can accept your URI route arguments as parameters with matching names
in your route target signature if you like but they'll always be available in the
$request['ROUTE_ARGS']
array as well.
Every client request follows one of three paths through the routing system:
- No request URI match is found:
404 Not Found
- A request URI is matched, but the HTTP verb does not match:
405 Method Not Allowed
- The request URI and HTTP method match a route and the associated target is invoked
One of Arya's goals is to retain PHP's ease of use while still exposing a standard API for middleware modification before and after each request.
Middleware Quick and Dirty
- Arya uses universal
Arya\Request
andArya\Response
instances for each page load; - Middleware may modify the universal request/response instances before or after route handlers;
- Middleware MUST return
TRUE/FALSE/NULL
and may only modify the request/response directly; - If a middleware returns
TRUE
then no more middleware of the same type (before/after/final) will execute; - "Before" middleware should only return
TRUE
if it assigns a response as Arya will treat this result as an indication that the route handler should not be invoked; - "After" middleware will always execute after "before" middleware and/or the routed application handler;
- @TODO Mention "Final" middleware (not yet operational)
@TODO Add URL rewriting example
The middleware concept is just as powerful for modifying responses after they're generated as it is for altering requests before they reach the application. Let's consider a standard use-case for an "after" middleware ...
Arya provides no built-in abstraction for custom error pages because the middleware system exposes all the necessary tools for a manual implementation. Let's say we want to capture all error responses and replace them with our own custom error page. All we need to do is specify an "after" middleware callable to capture and modify such responses before they're sent to the client ...
<?php
use Arya\Response, Arya\Application;
function myErrorPageMiddleware(Response $response) {
switch ($response->getStatus()) {
case 404:
$response->setBody('my custom 404 html');
break;
case 500:
$response->setBody('my custom 500 html');
break;
default:
// don't bother to modify any others
}
}
(new Application)
->route('GET', '/', function() { return 'Hello World'; })
->after('myErrorPageMiddleware')
->run();
What's going on in this example? All we've done is register a middleware class method to be invoked
after the application executes. Our myErrorPageMiddleware
function simply checks to see if
specific status codes were assigned and if so replaces the response entity body with our own custom
HTML. Note that middleware callables are provisioned in the same way as applications; all we
need to do is typehint our dependencies and they'll be provided automatically either in the
constructor or callable signature (wherever the middleware asks for them).
@TODO "Final" middleware not yet operational
Arya internally uses the Auyrn dependency injector.
To share our definitions, aliases etc. with Arya, we can pass our Auryn\Injector instance as the first argument to the Application constructor.
If no Auryn\Injector instance is passed, the Application class will instance its own injector.
Arya represents every request as an Arya\Request
instance. This class provides an object-oriented
alternative to the superglobal anti-pattern present by default in PHP web SAPI environments.
Request Mutability
Request
instances implement ArrayAccess
to provide mutability for middleware callables. In this
way it's possible for middleware components to alter the request to perform actions such as URI
rewriting.
Request Provisioning
Because route targets are automatically provisioned they must typehint the Arya\Request
class in
their method signatures (extended instance method targets may also typehint in __construct
). For
example, the following route targets demonstrate equivalent ways to ask for the request instance in
your application:
<?php
use Arya\Application, Arya\Request;
function myFunctionTarget(Request $request) {
return "Hello from " . $request['REQUEST_URI'];
}
class MyCtorRouteClass {
private $request;
function __construct(Request $request) {
$this->request = $request;
}
function myTarget() {
return "Hello from " . $this->request['REQUEST_URI'];
}
}
class MyMethodRouteClass {
function myTarget(Request $request) {
return "Hello from " . $request['REQUEST_URI'];
}
}
$app = (new Application)
->route('GET', '/function', 'myFunctionTarget')
->route('GET', '/my-ctor-route', 'MyCtorRouteClass::myTarget')
->route('GET', '/my-method-route', 'MyMethodRouteClass::myTarget')
->run()
;
One of the most user-friendly aspects of the PHP web SAPI is the ability to simply echo
output as
your HTTP response entity body. This approach, however, is suboptimal in terms of testability and
enterprise sustainability. In the spirit of simplifying HTTP Arya allows application callables to
return strings directly to generate a standard 200 response. Consider:
<?php
function helloWorld(Arya\Request $request) {
return "Hello from " . $request['REQUEST_URI'];
}
$app = new Arya\Application;
$app->route('GET', '/', function(Arya\Request $request) {
return "Hello from " . $request['REQUEST_URI'];
});
$app->run();
Arya actively prevents the manual output of response data via output buffering. If your application
generates any output (including error output) the result is a 500 Internal Server Error
response.
When in DEBUG mode you'll receive a helpful print-out containing the output data. In production
environments a generic 500 error message is displayed. This behavior is designed to funnel all
output through your route target return values so that "after" middleware callables have an
opportunity to inspect/modify output. Note that when in DEBUG mode this behavior also simplifies
n00b-core browser output debugging at runtime.
When your application needs fine-grained control over the HTTP response a simple string is not enough.
In these cases route targets may return an instance of the Arya\Response
class.
@TODO Talk about status code
@TODO Talk about headers
@TODO Talk about entity body
@TODO
@TODO Intro
@TODO
@TODO