README

Slim, fast and full compatible PSR-7 & PSR-15 routing library for PHP.

Why another routing library ?

Super fast using fastRoute algorithm algorithm.
Concise route syntax. Route parameters and optional route segments.
Built-in PSR-7 support.
Out of box PSR-15 middleware.

Installation

Install via the composer utility.

composer require "phoole/route"

or add the following lines to your composer.json

{
    "require": {
       "phoole/route": "1.*"
    }
}

Usage

Inject route definitions (pattern, handler, default values etc.) into the dispatcher and then call either match() or process().

use Phoole\Route\Router;
use GuzzleHttp\Psr7\ServerRequest;
use Psr\Http\Message\ServerRequestInterface;

$router = (new Router())
    ->addGet(
        '/blog/{action:xd}[/{year:d}[/{month:d}[/{date:d}]]]',
        function(ServerRequestInterface $request) {
            $params = $request->getAttribute(Router::URI_PARAMETERS);
            echo "action is " . $params['action'];
        }
    )->addPost(
        '/blog/post',
        'handler2'
    )->addRoute(new Route(
        'GET,HEAD',
        '/blog/read[/{id:d}]',
        'handler3',
        ['id' => '1'] // default values
    ));

// diaptcher (match & execute controller action)
$result = $router->match(new ServerRequest('GET', '/blog/list/2016/05/01'));

if ($result->isMatched()) {
    echo "WOW matched";
}

Or load routes from an array,

$routes = [
    ['GET', '/user/{action:xd}/{id:d}', 'handler1', ['id' => 1]],
    [ ... ],
    ...
];
$router = new Router($routes);

Route syntax

{Named} parameters

A route pattern syntax is used where {foo} specifies a named parameter or a placeholder with name foo and default regex pattern [^/]++. In order to match more specific types, you may specify a custom regex pattern like {foo:[0-9]+}.

// with 'action' & 'id' two named params
$dispatcher->addGet('/user/{action:[^0-9/][^/]*}/{id:[0-9]+}', 'handler1');

Predefined shortcuts can be used for placeholders as follows,

':d}'   => ':[0-9]++}',             // digit only
':l}'   => ':[a-z]++}',             // lower case
':u}'   => ':[A-Z]++}',             // upper case
':a}'   => ':[0-9a-zA-Z]++}',       // alphanumeric
':c}'   => ':[0-9a-zA-Z+_\-\.]++}', // common chars
':nd}'  => ':[^0-9/]++}',           // not digits
':xd}'  => ':[^0-9/][^/]*+}',       // no leading digits

The previous pattern can be rewritten into,

// with 'action' & 'id' two named params
$router->addGet('/user/{action:xd}/{id:d}', 'handler1');

[Optional] segments

Optional segments in the route pattern can be specified with [] as follows,
```
// $action, $year/$month/$date are all optional
$pattern = '/blog[/{action:xd}][/{year:d}[/{month:d}[/{date:d}]]]';
```
where optional segments can be NESTED. Unlike other libraries, optional segments are not limited to the end of the pattern, as long as it is a valid pattern like the [/{action:xd}] in the example.
Syntax limitations
- Parameter name MUST start with a character
  
  Since {2} has special meanings in regex. Parameter name MUST start with a character. And the use of {} inside/outside placeholders may cause confusion, thus is not recommended.
- [] outside placeholder means OPTIONAL segment only
  
  [] can not be used outside placeholders as part of a regex pattern, IF YOU DO NEED to use them as part of the regex pattern, please include them INSIDE a placeholder.
- Use of capturing groups () inside placeholders is not allowed
  
  Capturing groups () can not be used inside placeholders. For example {user:(root|phoole)} is not valid. Instead, you can use either use {user:root|phoole} or {user:(?:root|phoole)}.

Default Values

Default values can be added to named parameters at the end in the form of {action:xd=list}. Default values have to be alphanumeric chars. For example,

// $action, $year/$month/$date are all optional
$pattern = '/blog[/{action:xd=list}][/{year:d=2016}[/{month:d=01}[/{date:d=01}]]]';
$router->addGet($pattern, 'handler');

Routes

Same route pattern

User can define same route pattern with different http methods.

$router
    ->addGet('/user/{$id}', 'handler1')
    ->addPost('/user/{$id}', 'handler2');

Handlers

Handler resolving

Most of the time, matching route will return a handler like [ 'ControllerName', 'actionName' ]. Handler resolver can be used to resolving this pseudo handler into a real callable.

Users may write their own handler resolver by implementing Phoole\Route\Resolver\ResolverInterface.

Algorithms

FastRoute algorithm

This Fast Route algorithm is implemented in Phoole\Route\Parser\FastRouteParser class and explained in detail in this article "Fast request routing using regular expressions".

phoole/route uses this algorithm by default.
Comments on routing algorithms
- It does NOT matter that much as you may think.
  
  If you are using routing library in your application, different algorithms may differ only 0.1 - 0.2ms for a single request, which seems meaningless for an application unless you are using it as a standalone router.
- Try network routing or server routing if you just CRAZY ABOUT THE SPEED.

Testing

$ composer test

Dependencies

PHP >= 7.2.0

Appendix

Routing issues

Base on the request informations, such as request device, source ip, request method etc., service provider may direct request to different hosts, servers, app modules or handlers.
- Network level routing
  
  Common case, such as routing based on request's source ip, routes the request to a NEAREST server, this is common in content distribution network (CDN), and is done at network level.
- Web server routing
  
  For performance reason, some of the simple routing can be done at web server level, such as using apache or ngix configs to do simple routing.
  
  For example, if your server goes down for maintenance, you may replace the .htaccess file as follows,
```
DirectorySlash Off
Options -MultiViews
DirectoryIndex maintenance.php
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule ^ maintenance.php [QSA,L]
```
- App level routing
  
  It solves much more complicated issues, and much more flexible.
  
  Usually, routing is done at a single point index.php. All the requests are configured to be handled by this script first and routed to different routines.

phoole / route

Maintainers

Details