A PHP Christmas Miracle - 3 Frameworks, 1 app

A PHP Christmas Miracle

Ryan Weaver@weaverryan

A story of deception, wisdom, and finding our common interface

Saturday, December 3, 11

Who is this dude?

• Co-author of the Symfony2 Docs

• Core Symfony2 contributor

• Co-owner of KnpLabs US

• Fiancee of the much more talented @leannapelham

http://www.knplabs.com/enhttp://www.github.com/weaverryan

@weaverryanSaturday, December 3, 11

http://www.knplabs.com/en

http://www.knplabs.com/en

http://www.github.com/weaverryan

http://www.github.com/weaverryan

Act 1:

A History of modern PHP


First, the facts


To put it politely...


We have a surplus of PHP frameworks


To put it honestly...


We have a sh*tload


‣ Symfony‣ Zend Framework‣ Lithium‣ Aura (formerly Solar)‣ Code Igniter‣ Yii‣ Cake‣ Fuel‣ Akelos‣ Kohana‣ Flow3‣ ...


And we solve common problems


‣ HTTP classes (e.g. request, response)‣ Routing‣ Controllers‣ Templates‣ Loggers‣ Database tools‣ Service containers‣ Security‣ Serialization

‣ Forms‣ Events‣ Mailing‣ Validation‣ Pagination‣ Menus‣ Search

Common Problems


Lack of sharing means duplicated efforts


But, there is some hope...


PSR-0

• The PHP community came together, sang Kumbaya and wrote up some class-naming standards

• PSR-0 isn’t a library, it’s just an agreement to name your classes in one of two ways


PSR-0 with namespaces

class: Symfony\Component\HttpFoundation\Request

path: vendor/src/Symfony/Component/HttpFoundation/Request.php

Namespace your classes and have the namespaces follow the directory structure


PSR-0 with underscores

class: Twig_Extension_Core

path: vendor/twig/lib/Twig/Extension/Core.php

Use underscores in your classes and follow the directory structure


But what does this mean?

• An "autoloader" is a tool you can use so that you don't have to worry about “including” classes before you use them

• Use anyone’s autoloader

• We're all still duplicating each other's work, but at least everyone’s autoloader does the same thing


What else can we agree on?


So far, not much


But we’ll see how all the libraries can still work

together


And we can always hope for a Christmas miracle


Act 2:

Starting with a Horrible App


How many of you use a framework on a regular

basis?


How many of you have been told that it's a bad idea to not

use a framework?


Was I the one who told you that?


Today we’re going to break the rules...


... build a framework from “scratch” ...


... and see why that’s no longer necessarily a bad

thing.


• Refactor a crappy flat PHP application into a framework that makes sense

• Use as many libraries from as many quarreling PHP tribes as possible‣ Symfony‣ Zend Framework‣ Lithium‣ ... only lack of time prevents more...

Today’s 2 goals:


Our starting point

• Our app is a single file that fuels two pages

http://bit.ly/php-xmas

• Following along with the code of our app at:




• Shucks, we even have a database connection


Open our Database connection

try { $dbPath = __DIR__.'/data/database.sqlite'; $dbh = new PDO('sqlite:'.$dbPath);} catch(PDOException $e) { die('Panic! '.$e->getMessage());}

// index.php


Try to get a clean URI

$uri = $_SERVER['REQUEST_URI'];if ($pos = strpos($uri, '?')) { $uri = substr($uri, 0, $pos);}

// index.php


Render the homepage

if ($uri == '/' || $uri == '') { echo '<h1>Welcome to PHP Santa</h1>'; echo '<a href="/letters">Readletters</a>'; if (isset($_GET['name'])) { echo sprintf( '<p>Oh, and hello %s!</p>', $_GET['name'] ); }}

// index.php


Print out some lettersif ($uri == '/letters') {

$sql = 'SELECT * FROM php_santa_letters'; echo '<h1>Read the letters to PHP Santa</h1>'; echo '<ul>'; foreach ($dbh->query($sql) as $row) { echo sprintf( '<li>%s - dated %s</li>', $row['content'], $row['received_at'] ); } echo '</ul>';}

// index.php


Got it?


Great, let’s clean this mess up


Act 3:

Symfony's HTTP Foundation


• Our code for trying to get a clean URL is a bit archaic and probably error prone

• We're echoing content from our controllers, maybe we can evolve

Problems


• Symfony’s HttpFoundation Component

• Gives us (among other things) a solid Request and Response class

Solution


Bring in HttpFoundation

mkdir -p vendors/Symfony/Component

git submodule add \ git://github.com/symfony/HttpFoundation.git \ vendors/Symfony/Component/HttpFoundation/

git submodule add \ git://github.com/symfony/ClassLoader.git \ vendors/Symfony/Component/ClassLoader


Current Status


• No matter what framework or libraries you use, you’ll need an autoloader

• We’ll use Symfony’s “ClassLoader”

• Each PSR-0 autoloader is very similar

Autoloading


Create a bootstrap file<?php// bootstrap.php

require __DIR__.'/vendors/Symfony/Component/ClassLoader/UniversalClassLoader.php';use Symfony\Component\ClassLoader\UniversalClassLoader;

// setup the autoloader$loader = new UniversalClassLoader();$loader->registerNamespace( 'Symfony', __DIR__.'/vendors');$loader->register();


... and include it

<?php// index.phprequire 'bootstrap.php';

// ...


So how does this help?


$uri = $_SERVER['REQUEST_URI'];if ($pos = strpos($uri, '?')) { $uri = substr($uri, 0, $pos);}

use Symfony\Component\HttpFoundation\Request;$request = Request::createFromGlobals();

// the clean URI - a lot of logic behind it!!!$uri = $request->getPathInfo();

... becomes ...


if (isset($_GET['name'])) { echo sprintf( '<p>Oh, and hello %s!</p>', $_GET['name'] );}

if ($name = $request->query->get('name')) { echo sprintf(

'<p>Oh, and hello %s!</p>',$name

);}

... becomes ...


• Normalizes server variables across systems

• Shortcut methods to common things like getClientIp(), getHost(), getContent(), etc

• Nice object-oriented interface

The “Request” object


• We also have a Response object

• Instead of echoing out content, we populate this fluid object

The “Response” object


header("HTTP/1.1 404 Not Found");echo '<h1>404 Page not Found</h1>';echo '<p>This is most certainly *not* an xmas miracle</p>';

$content = '<h1>404 Page not Found</h1>';$content .= '<p>This is most certainly *not* an xmas miracle</p>';

$response = new Response($content);$response->setStatusCode(404);$response->send();

... becomes ...


Act 4:

Routing


• Our app is a giant gross “if” statementProblems

if ($uri == '/' || $uri == '') { // ...} elseif ($uri == '/letters') { // ...} else { // ...}

• Grabbing a piece from the URL like /blog/my-blog-post will take some work


• Lithium’s Routing library

• Routing matches URIs (e.g. /foo) and returns information we attached to that URI pattern

• All the nasty regex matching is out-of-sight

Solution


3 Steps to Bringing in an external tool


git submodule add git://github.com/UnionOfRAD/lithium.git vendors/lithium

#1 Download the library


// bootstrap.php// ...

$loader = new UniversalClassLoader();$loader->registerNamespace('Symfony', __DIR__.'/vendors');$loader->registerNamespace('lithium', __DIR__.'/vendors');

$loader->register();

#2 Configure the autoloader


use lithium\net\http\Router;$router = new Router();// ...

#3 Celebrate!


@weaverryan

Current Status


So how do we use the router?


Full disclosure: “use” statements I’m hiding from the

next page

use Symfony\Component\HttpFoundation\Request;use lithium\net\http\Router;use lithium\action\Request as Li3Request;


$request = Request::createFromGlobals();$li3Request = new Li3Request();// get the URL from Symfony's request, give it to lithium$li3Request->url = $request->getPathInfo();

a) Map URI to “controller”

// create a router, build the routes, and then execute it$router = new Router();$router->connect('/letters', array('controller' => 'letters'));$router->connect('/', array('controller' => 'homepage'));$router->parse($li3Request);

if (isset($li3Request->params['controller'])) { $controller = $li3Request->params['controller'];} else { $controller = 'error404';}


// execute the controller, send the request, get the response$response = call_user_func_array($controller, array($request));if (!$response instanceof Response) { throw new Exception(sprintf( 'WTF! Your controller "%s" didn\'t return a response!!', $controller ));}

$response->send();

b) Execute the controller*

* each controller is a flat function Saturday, December 3, 11

function homepage(Request $request) { $content = '<h1>Welcome to PHP Santa</h1>'; $content .= '<a href="/letters">Read the letters</a>'; if ($name = $request->query->get('name')) { $content .= sprintf( '<p>Oh, and hello %s!</p>', $name ); }

return new Response($content);}

The Controllers


function letters(Request $request){ global $dbh;

$sql = 'SELECT * FROM php_santa_letters'; $content = '<h1>Read the letters to PHP Santa</h1>'; $content .= '<ul>'; foreach ($dbh->query($sql) as $row) { $content .= sprintf( '<li>%s - dated %s</li>', $row['content'], $row['received_at'] ); } $content .= '</ul>';

return new Response($content);}

The Controllers$kitten--


function error404(Request $request){ $content = '<h1>404 Page not Found</h1>'; $content .= 'This is most certainly *not* an xmas miracle';

$response = new Response($content); $response->setStatusCode(404);

return $response;}

The Controllers


1. Request cleans the URI2. Router matches the URI to a route, returns a “controller” string3. We execute the controller function4. The controller creates a Response object5. We send the Response headers and content

The Big Picture


Your 20 line framework


Act 5:

Pimple!


• We’ve got lots of random, disorganized objects floating around

Problems

• And we can’t easily access them from within our controllers

@weaverryan

function letters(Request $request){ global $dbh;

// .... }


• Pimple! - a Dependency Injection Container

• Dependency Injection Container:

the scariest word we could think of todescribe an array of objects on steroids

Solution


Remember: 3 Steps to bringing in an external tool


git submodule add git://github.com/fabpot/Pimple.git vendors/Pimple




require __DIR__.'/vendors/Pimple/lib/Pimple.php';


actually, it’s only one file - so just require it!


$c = new Pimple();

#3 Celebrate!


• Use Pimple to create and store your objects in a central place

• If you have the Pimple container object, then you have access to every other object in your application

Pimple Creates Objects


$c = new Pimple();

$c['connection'] = $c->share(function() { $dsn = 'sqlite:'.__DIR__.'/data/database.sqlite'; return new PDO($dsn);});

Centralize the db connection


Centralize the db connection

$c1 = $c['connection'];$c2 = $c['connection'];

// they are the same - only one object is created!$c1 === $c2


• So far, we’re using a “global” keyword to access our database connection

• But if we pass around our Pimple container, we always have access to anything we need - including the database connection

Access to what we need


Pass the container to the controller

$c = new Pimple();

// ...

$response = call_user_func_array( $controller, array($request, $c));


function letters(Request $request, Pimple $c){ $dbh = $c['connection'];

$sql = 'SELECT * FROM php_santa_letters'; $content = '<h1>Read the letters to PHP Santa</h1>'; $content .= '<ul>'; foreach ($dbh->query($sql) as $row) { // ... } // ...}

$kitten++


What else?

How about configuration?


$c = new Pimple();

// configuration$c['connection_string'] = 'sqlite:'.__DIR__ .'/data/database.sqlite';

$c['connection'] = $c->share(function(Pimple $c) { return new PDO($c['connection_string']);});


Further?

What about dependencies?


$c['request'] = $c->share(function() { return Request::createFromGlobals();});

$c['li3_request'] = $c->share(function($c) { $li3Request = new Li3Request(); $li3Request->url = $c['request']->getPathInfo();

return $li3Request;});

// ...$li3Request = $c['li3_request'];


With everything in the container, our “framework”

just got skinny


$c = new Pimple();// create objects in Pimple

// execute our routing, merge attributes to request$result = $c['router']->parse($c['li3_request']);$c['request']->attributes ->add($c['li3_request']->params);

// get controller and execute!$controller = $c['request']->attributes ->get('controller', 'error404');$response = call_user_func_array( $controller, array($c['request'], $c));

$response->send();Saturday, December 3, 11

Logging with ZF2


• I don’t have enough frameworks in my framework

Problems

• Oh yeah, and we need logging...


• Zend Framework2

• ZF2 has a ton of components, including a logger

Solution


3 Steps to bringing in an external tool


git submodule add git://github.com/zendframework/zf2.git vendors/zf2




$loader = new UniversalClassLoader();$loader->registerNamespace('Symfony', __DIR__.'/vendors');$loader->registerNamespace('lithium', __DIR__.'/vendors');$loader->registerNamespace( 'Zend', __DIR__.'/vendors/zf2/library');

$loader->register();



use Zend\Log\Logger;use Zend\Log\Writer\Stream;

$logger = Logger($pimple['logger_writer']);

#3 Celebrate!

Yes we did just bring in a 100k+ lines of code for a simple logger :)


Current Status


use Zend\Log\Logger;use Zend\Log\Writer\Stream;

$c['log_path'] = __DIR__.'/data/web.log';$c['logger_writer'] = $c->share(function($pimple) { return new Stream($pimple['log_path']);});

$c['logger'] = $c->share(function($pimple) { return new Logger($pimple['logger_writer']);});

Create the Logger in our Fancy Container


http://web.log

http://web.log

function error404(Request $request, Pimple $c){ $c['logger']->log( 'Crap, 404 for '.$request->getPathInfo(), Logger::ERR ); $content = '<h1>404 Page not Found</h1>'; // ...}

And use it anywhere


Getting kinda easy, right?


What other libraries can you think to integrate?


Getting Organized


• Our application has 4 major parts:1) autoloading setup2) Creation of container3) Definition of routes4) Definition of controllers5) The code that executes everything

• For our business, only #3 and #4 are important

• ... but it’s all jammed together

Problems


• Some definitions

“Application” - the code that makes you money

“Framework” - under-the-hood code that impresses your geek friends

• To be productive, let’s “hide” the framework

Solution


• Our app basically has 2 files

‣ bootstrap.php: holds autoloading‣ index.php: holds

- container setup- definition of routes- definition of controllers- the code that executes it all

Starting point


‣ bootstrap.php: holds- autoloading- container setup- the code that executes it all

(as a function called _run_application())‣ controllers.php: holds controllers‣ routes.php: holds routes

‣ index.php: pulls it all together

Ending point


<?php

// index.php$c = require 'bootstrap.php';require 'routing.php';require 'controllers.php';

$response = _run_application($c);$response->send();

Nothing to see here...


// bootstrap.phpfunction _run_application(Pimple $c){ $c['router']->parse($c['li3_request']); $c['request']->attributes ->add($c['li3_request']->params);

$controller = $c['request']->attributes ->get('controller', 'error404');

return call_user_func_array( $controller, array($c['request'], $c) );}

“Framework” hidden away...


// routing.php$c['router']->connect( '/letters', array('controller' => 'letters'));

$c['router']->connect( '/{:name}', array( 'controller' => 'homepage', 'name' => null ));

Routes have a home


// controllers.phpuse Symfony\Component\HttpFoundation\Request;use Symfony\Component\HttpFoundation\Response;

function homepage(Request $request) { // ...}

function letters(Request $request, $c){ // ...}

function error404(Request $request){ // ...}

Controllers have a home


To make $$$, work in routes.php and controllers.php


Final Thoughts


It doesn’t matter if you use a framework...


... inherited a legacy spaghetti system...


... or practice “not-invented-here” development


...an innumerable number of tools are available...


... so you can stop writing your framework ...


... and start writing your application


What’s available? Search GitHub


Thanks!Questions?

Ryan Weaver@weaverryan


• http://bit.ly/php-xmas• http://github.com/symfony• https://github.com/UnionOfRAD/lithium• https://github.com/zendframework/zf2• http://pimple.sensiolabs.org/

References

@weaverryan

And if we had more time...• http://twig.sensiolabs.org/• https://github.com/knplabs/KnpMenu• https://github.com/Seldaek/monolog• https://github.com/avalanche123/Imagine




http://github.com/symfony

http://github.com/symfony

https://github.com/UnionOfRAD/lithium

https://github.com/UnionOfRAD/lithium

https://github.com/zendframework/zf2




http://pimple.sensiolabs.org

http://pimple.sensiolabs.org

http://twig.sensiolabs.org/

http://twig.sensiolabs.org/

https://github.com/Seldaek/monolog

https://github.com/Seldaek/monolog

https://github.com/avalanche123/Imagine

https://github.com/avalanche123/Imagine

A PHP Christmas Miracle - 3 Frameworks, 1 app

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Transcript of A PHP Christmas Miracle - 3 Frameworks, 1 app