README

See new lib at phoole/route Introduction

phossa-route is a fast, full-fledged and feature-rich application level routing library for PHP. It dispatches requests base on URLs, HTTP headers, session informations etc.

It requires PHP 5.4 and supports PHP 7.0+, HHVM. It is compliant with PSR-1, PSR-2, PSR-4.

Why another routing library ?

Super fast ! If it matters to you.
Support different routing strategies and combinations of these strategies.
Support different regular expression routing algorithms including the fastRoute algorithm
Concise route syntax. Route parameters and optional route segments.
Multiple routing collections allowed.
Different level of default handlers.
Fine control of routing process by multiple level of extensions.
Filtering request's other fields during the matching
Route and regex debugging.
Dependency injection ready. Support third-party Di libraries.

Getting started

Installation

Install via the composer utility.

composer require "phossa/phossa-route=1.*"

or add the following lines to your composer.json

{
    "require": {
      "phossa/phossa-route": "^1.0.0"
    }
}

Simple usage

use Phossa\Route\Dispatcher;

// dispatcher with default collector & resolver
$dispatcher = (new Dispatcher())
    ->addGet(
        '/blog/{action:xd}[/{year:d}[/{month:d}[/{date:d}]]]',
        function($result) {
            echo "action is " . $result->getParameter('action');
        })
    ->addPost('/blog/post', 'handler2')
    ->addRoute(new Route\Route(
        'GET,HEAD', // multiple methods
        '/blog/read[/{id:d}]',
        'handler3',
        ['id' => '1'])); // default $id value

// route base on info provided by server
$dispatcher->dispatch();

Load routes from file

use Phossa\Route\Dispatcher;

/*
 * routes.php :
 * return [
 *     '/user/phossa'  => 'handler1',
 *     '/user/{action:xd}/{id:d}'   => [['controller', 'action'], 'GET,POST'],
 *     '/user/view[/{id:d}]' => ['handler2', 'GET', ['id' => 23]]
 * ];
 */
$dispatcher = (new Dispatcher())->loadRoute('./routes.php');

Route syntax

NOTE: Support for other route library syntax is on the release 1.1.x list. User may pick his/her favorite route syntax with phossa-route :).

{Named} parameters

A route pattern syntax is used where {foo} specifies a named parameter or a placeholder with name foo and default 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
$dispatcher->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|phossa)} is not valid. Instead, you can use either use {user:root|phossa} or {user:(?:root|phossa)}.
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}]]]';
```

Routes

Defining routes with dispatcher

You may define routes with dispatcher, but it is actually defining routes with the first collector (route collection) in the dispatcher.
```
$dispatcher = (new Dispatcher())->addPost('/blog/post', 'handler2');
```
addGet() and addPost() are wrappers of addRoute(RouteInterface).

Multiple routing collectors

Routes can be grouped into different collections by using multiple collectors.

// '/user' related
$collector_user = (new Route\Collector\Collector())
    ->addGet('/user/list/{id:d}', 'handler1')
    ->addGet('/user/view/{id:d}', 'handler2')
    ->addPost('/user/new', 'handler3');

// '/blog' related
$collector_blog = (new Route\Collector\Collector())
    ->addGet('/blog/list/{user_id:d}', 'handler4')
    ->addGet('/blog/read/{blog_id:d}', 'handler5');

$dispatcher->addCollector($collector_user)
           ->addCollector($collector_blog);

Same route pattern

User can define same route pattern with different http methods.
```
$dispatcher
    ->addGet('/user/{$id}', 'handler1')
    ->addPost('/user/{$id}', 'handler2');
```
But can not define same route pattern same method with different filters. The possible solution is dealing logic in handler1 or add extensions to the route.

Dispatching

Dispatch with dispatcher's dispatch()

In the script index.php, the dispatch() is normally the last line.
```
// index.php
// ...

// dispatch base on server request info
$dispatcher->dispatch();
```
dispatch() takes one optional argument Phossa\Route\Context\ResultInterface. When none provided, it will collect informations from super globals like $_SERVER and $_REQUEST and dispatches to the right routine or callable base on route definition.

Dispatch an URL

User may dispatch an URL,

$dispatcher->dispatchUrl('GET', '/error404');

Match instead of dispatching

Instead of executing handler by default in dispatch(), more control by user if using the match() method

// use info from $_SERVER etc.
if ($dispatcher->match()) {
    $result = $dispatcher->getResult();
    switch($result->getStatus()) {
        case 200:
          // ...
          break;
        case 404:
          // ...
          break;
        default:
          // ...
          break;
    }
} else {
    // no match found
    // ...
}

matchUrl() is also provided.

Handlers

Multiple handlers

Route is defined with one handler for status 200 OK. Multiple handlers are supported for other result status.

use Phossa\Route\Route;
use Phossa\Route\Status;

$route = (new Route('GET', '/user/{action:xd}/{id:d}',
    function($result) { // handler for Status::OK
        $user_id = $result->getParameter('id');
        // ...
    })->addHandler(Status::METHOD_NOT_ALLOWED, 'handler1'); // extra handler

Handler handler1 will be executed if route is matched but method is not valid.

Default handlers

Dispatcher and collectors can have multiple handlers corresponding to different status. If the result has no handler set, then the collector's handler(same status code) will be retrieved. If still no luck, the dispatcher's handler (same status code) will be used if defined.

Dispatcher-level handlers,
```
use Phossa\Route\Status;

$dispatcher->addHandler(
    Status::SERVICE_UNAVAILABLE,
    function($result) {
        // ...
    }
);
```
Collector-level handlers,
```
$collector->addHandler(
    Status::MOVED_PERMANENTLY,
    function($result) {
        // ...
    }
);
```
Handler resolving

Most of the time, routes returns a handler like [ 'className', 'method' ]. Handler resolver can be used to resolving this pseudo handler into a real callable.
```
use Phossa\Route;

// dispatcher with default resolver
$dispatcher = new Route\Dispatcher(
    new Route\Collector\Collector(),
    new Route\Handler\ResolverAbstract()
);
```
Users may write their own handler resolver by extending Phossa\Route\Handler\ResolverAbstract class.

Extensions

Extensions are executables dealing with the matching result or other tasks before or after certain dispatching stages.

Use of extensions

Extensions MUST return a boolean value to indicate wether to proceed with the dispatching process or not. FALSE means stop and returns to top level, the dispatcher level.

use Phossa\Route\Dispatcher
use Phossa\Route\Extensions\RedirectToHttpsExtension;

// create dispatcher
$dispatcher = new Dispatcher();

// direct any HTTP request to HTTPS port before any routing
dispatcher->addExtension(new RedirectToHttpsExtension());

Force authentication for any '/user' prefixed URL,

$dispatcher->addExtension(
    function($result) {
        $pattern = $result->getRequest()->getPattern();
        if ('/user' == substr($pattern, 0, 5) && !isset($_SESSION['auth'])) {
            $result->setStatus(Status::UNAUTHORIZED);
            return false; // return to dispatcher level
        }
        return true; // authed or not in /user
    },
    Dispatcher::BEFORE_MATCH // run this extension before matching
);

// set default auth handler at dispatcher level
$dispatcher->addHandler(
    Status::UNAUTHORIZED,
    function($result) {
        // display auth page etc.
    }
);

Examples of extension

Validation of a parameter value,

$route->addExtension(
    function($result) {
        $id = (int) $result->getParameter('id');
        if ($id > 1000) { // not allowed
            $result->setStatus(Status::PRECONDITION_FAILED);
            return false;
        }
        return true;
    },
    Route::BEFORE_ROUTE // before execute route handler
);

Statistics for a route collection

$collector->addExtension(
    function($result) {
        // collect statistics
    },
    Collector::BEFORE_COLL // before collector match
)->addExtension(
    function($result) {
        // collect statistics
    },
    Collector::AFTER_COLL // after a successful match
);

Extension stages

Three types of stages, dispatcher level, collector level and route level. List of all stages in the order of execution.
- Dispatcher::BEFORE_MATCH before matching starts
  - Collector::BEFORE_COLL before matching in a collector
  - Collector::AFTER_COLL after a successful match in the collector
- Dispatcher::AFTER_MATCH after a successful match at dispatcher level
- Dispatcher::BEFORE_DISPATCH after a sucessful match, before dispatching to any handler
  - Route::BEFORE_ROUTE before executing handler(route's or collector's) for this route
  - Route::AFTER_ROUTE after handler successfully executed
- Dispatcher::AFTER_DISPATCH back to dispatcher level, after handler executed successfully
- Dispatcher::BEFORE_DEFAULT match failed or no handler found for the matching route, before execute dispatcher's default handler
- Dispatcher::AFTER_DEFAULT after dispatcher's default handler executed

Filters

Filter usage

Sometimes, user may want to look at other information before deciding on how to dispatch. Extensions is one way of doing this. But addFilter() of the $route object is a more appropriate way at route level.

// match against $_SERVER, $_REQUEST, $_SESSION, $_COOKIE etc.
$route = (new Route('GET', '/user/list/{$id}', 'handler1'))
    ->addFilter('server.server_name', '(m|www).phossa.com')
    ->addFilter('cookie.vote_status', 'voted');

Even closure is supported

// closure takes the value from $_SERVER['SERVER_NAME'] as input
$route->addFilter('server.server_name', function($value) {
    switch($value) {
      case 'a1.phossa.com':
      case 'b2.phossa.com':
          return true;
      default:
          return false; // always return a bool
    }
});

Difference with extension

Filters are used during the matching process, if filtering failed for the route, the matching process will still try the next route.

While route level extensions are executed after a successful match and just before execution of the handler.

Debugging

Sometimes, you need to know what went wrong.

$dispatcher->setDebugMode(true)->setDebugger($logger);

Where $logger is a PSR-3 compatible logger implmenting the interface Psr\Log\LoggerInterface. The dispatcher will send logs of dispatching process to the logger.

Routing strategies

There are a couple of URL based routing strategies supported in this library. Different strategy collectors can be combined together into one dispatcher.

Query Parameter Routing (QPR)

The routing info is directly embedded in the URL query. The advantage of this scheme is fast and clear.
```
http://servername/path/?r=controller-action-id-1-name-nick
```
This strategy is implemented in Phossa\Route\Collector\CollectorQPR class.
Parameter Pairs Routing (PPR)

Using parameter and value pairs as follows,
```
http://servername/path/index.php/controller/action/id/1/name/nick
```
Parameters order can be arbitary, but have to appear in pairs. Advantage of this scheme is fast and web crawler friendly. If URL rewriting is used, the above can be written into the following,
```
http://servername/path/controller/action/id/1/name/nick
```
Instead of using '/' as the parameter seperator, any URL valid characters except for the '?' and '&' can be used as a seperator.
```
http://servername/path/controller-action-id-1-name-nick
```
This strategy is implemented in Phossa\Route\Collector\CollectorPPR class.

Regular Expression Routing (RER)

Regular expression based routing is the default routing strategy for this library and implemented in Phossa\Route\Collector\Collector class.

// created with default RER collector
$dispatcher = new Dispatcher();

// add supprot for legacy query parameter routing
$dispatcher->addCollector(new CollectorQPR());

Regex matching algorithms

Different regex matching algorithms can be used with the RER collector.

FastRoute algorithm

This Group Count Based algorithm is implemented in Phossa\Route\Regex\ParserGcb class and explained in detail in this article "Fast request routing using regular expressions".

phossa-route uses this algorithm by default.
Standard algorithm

This algorithm is developed by phossa-route and a little bit slower than the fastRoute GCB algorithm. It is implemented in Phossa\Route\Regex\ParserStd class.

Use this standard algorithm,
```
use Phossa\Route\Dispatcher;
use Phossa\Route\Regex\ParserStd;
use Phossa\Route\Collector\Collector;

// use standard algorithm
$dispatcher = new Dispatcher(new Collector(new ParserStd));
```
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.
- If you DO care about routing speed
  
  Use different routing strategy like Parameter Pairs Routing (PPR) which is much faster than the regex based routing. Also by carefully design your routes, you may achieve better results even if you are using a slower algorithm.
- Try network routing or server routing if you just CRAZY ABOUT THE SPEED.

Dependencies

PHP >= 5.4.0
phossa/phossa-shared >= 1.0.6
phossa/phossa-logger >= 1.0.0 if you are using debugging

License

MIT License

Appendix

Performance
- Worst-case matching
  
  This benchmark matches the last route and unknown route. It generates a randomly prefixed and suffixed route in an attempt to thwart any optimization. 1,000 routes each with 8 arguments.
  
  This benchmark consists of 14 tests. Each test is executed 1,000 times, the results pruned, and then averaged. Values that fall outside of 3 standard deviations of the mean are discarded.
  
  "Parameter Pairs Routing (PPR)" is fastest and used as baseline.
- First route matching
  
  This benchmark tests how quickly each router can match the first route. 1,000 routes each with 8 arguments.
  
  This benchmark consists of 7 tests. Each test is executed 1,000 times, the results pruned, and then averaged. Values that fall outside of 3 standard deviations of the mean are discarded.
  
  Note Both FastRoute and Phroute implement a static route table, so they are fast at the first route matching (which is a static route)

URL rewrite

Setup URL rewriting to do routing with index.php

Apache .htaccess with mod_rewrite engine is on

DirectorySlash Off
Options -MultiViews
DirectoryIndex index.php
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule ^ index.php [QSA,L]

and in your httpd.conf file to enable using of .htaccess

<VirtualHost *:80>
  ServerAdmin me@mysite.com
  DocumentRoot "/path/www.mysite.com/public"
  ServerName mysite.com
  ServerAlias www.mysite.com

  <Directory "/path/www.mysite.com/public">
    Options -Indexes +FollowSymLinks +Includes
    AllowOverride All
    Order allow,deny
    Allow from all
  </Directory>
</VirtualHost>

Nginx configration in nginx.conf

server {
    listen       80;
    server_name  www.mysite.com mysite.com;
    root         /path/www.mysite.com/public;

    try_files $uri $uri/ /index.php$is_args$args;

    location /index.php {
        fastcgi_connect_timeout 3s;
        fastcgi_read_timeout 10s;
        include fastcgi.conf;
        fastcgi_pass 127.0.0.1:9000;
    }
}

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.

phossa / phossa-route

Maintainers

Details