6CS028 Workshop - Web Frameworks

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Main Page >> Advanced Web Technologies >> Workbook >> Week 02

Consider using a PHP framework for your assessment. Here are some popular ones:

Summary of findings

  • CodeIgniter: Possibly the easiest one the learn first (flexible, no command line)
  • Yii: A bit more tricky as you need to run a few commands (to create an app, to use scaffolding)
  • CakePHP: Quite simple to install (no command line required), but might be a bit more difficult to learn (I can't get mod rewrite to work at the moment)
  • Laravel: Working fine, although installation is not straight forward.
  • Symfony: Difficult to set-up (see my notes) and seems to be using a lot of RAM on the server :/
  • Zend: I can't get this to work on mi-linux

Command line

Some of the frameworks expect you to type commands, using the command line. Don't let it put you off, unless you know absolutely NOTHING about Linux commands.

From Windows simply start "Putty", installed in the all the labs, and free to download from home.

When starting Putty simply type "mi-linux.wlv.ac.uk" in the "host name" box, and press "enter". Then log in using your normal details.

Useful commands

To make a whole folder + sub-folders readable and executable by all: 

chmod 755 codeigniter/ -R

To remove a whole folder (WARNING - CANNOT BE UNDONE) 

rm codeigniter/ -R

Link to external CSS, JS, Images etc

Codeigniter

First make sure your base URL is populated in your config.php file, so for example for me: 

$config['base_url']='http://mi-linux.wlv.ac.uk/~in9352/codeigniter/';

Then upload your files in your "codeigniter" folder, or in suitable sub-folders (codeigniter/images, codeigniter/css and codeigniter/js). Do NOT upload the files into your codeigniter/application folder or any of its sub folders.

In the example below I have uploaded an image and a CSS file at the following locations:

  • codeigniter/css/style.css
  • codeigniter/funnycat.jpg

Finally use the "Base URL" helper in your view: 

<?$this->load->helper('url');?>
<html>
<head>
   <title><?php echo $title ?> - CodeIgniter 2 Tutorial</title>
   <link rel="stylesheet" type="text/css" href="<?=base_url("css/style.css")?>">
</head>
<body>
   <h1>CodeIgniter 2 Tutorial</h1>
<p>
<img src="<?=base_url("funnycat.jpg")?>">
</p>

Yii

Upload your files to your application folder, for example:

  • yii/myapp/images (for images)
  • yii/myapp/css (for css files)

Then simply use the getBaseUrl() helper in your views, like this: 

<img src="<?=Yii::app()->getBaseUrl(true)?>/images/Chrysanthemum.jpg" width=300>

CodeIgniter

I tested version 2.1.4:

First install CodeIgniter using this tutorial:

If successfully installed you should see this page:

Note: replace "in9352" with your student number and "codeigniter" with the folder name in which you have installed the framework.

Then work through the first few tutorials:

Nothing too complicated in the tutorials above, however I recommend that you skip the "Routing" section for now, as it make the format of the URL more confusing. Stick to the standard format for now: 

[your-site-url]index.php/controller/method

So far example: 

http://mi-linux.wlv.ac.uk/~in9352/codeigniter/index.php/pages/view

Yii

I tested version 1.1.14:

Note: you may want to download the .zip archive from the downloads section, it's easier to work with on Windows.

You can start here:

Ignore the "Apache and Nginx configurations" step for now and go straight to the "Creating First Yii Application" step.

Create first app

The tutorial tells you to create your first project by running the following command (see above for more on how to run commands): 

% YiiRoot/framework/yiic webapp WebRoot/myapp

The above worked for me, but one student tells me he is getting a "permission denied" error, which might mean you are not allowed to run bash commands. Not to worry, the script above also comes as a PHP script, so you can run this instead: 

php YiiRoot/framework/yiic.php webapp WebRoot/myapp

Obviously in both cases you need to specify the paths as per your folders.

When browsing to your newly created application you might get the odd error message telling you to make certain folders writable (e.g. myapp/protected/runtime)

Mysql Database

By default Yii is set up to access an SQLite database. If you want to use Mysql you will need to edit the protected/config/main.php file, uncomment the following block and add your usual Mysql connection details: 

'db'=>array(
	'connectionString' => 'mysql:host=localhost;dbname=XXX',
	'emulatePrepare' => true,
	'username' => 'XXX',
	'password' => 'XXX',
	'charset' => 'utf8',
),

Gii

Gii is a new tool that allows you to generate code from the database (aka Scaffolding in the lecture slides). You enable it by uncommenting the following block in the protected/config/main.php file. 

'gii'=>array(
	'class'=>'system.gii.GiiModule',
	'password'=>'1234',
	// If removed, Gii defaults to localhost only. Edit carefully to taste.
	'ipFilters'=>array('134.220.251.99','::1'),
),

Note: you need to specify your own password. Also I've had to put my IP address in the last field, or else the page was telling me I wasn't allowed in! On Windows you can get your IP address by opening a command line window and typing the command "ipconfig".

Other than that this seems to work quite well :) Obviously Gii can only create the php files if you make the folders writable (e.g. to generate a model class, you need to make the protected/models folder writable!)

CakePHP

I tested version 2.4.5

mod_rewrite

IMPORTANT: I can't get MOD REWRITE to work at the moment, so my clean URL doesn't work:

Instead I have to use the full URL, which is not great:

I'll update you if I get it working :)

Cache

If you are getting the following error message:

Warning: _cake_core_ cache was unable to write 'cake_dev_en-gb' to File cache in /studhome/staff/acad/in9352/public_html/cake/lib/Cake/Cache/Cache.php on line 309

You need to make the "app/tmp" folder (and all its sub-folders) writable by all in order to solve this.

PHP markers

Don't forget the <?php markers at the beginning of your Conrtoller and Model files, they are omitted in the tutorial.

Symfony

I tested version 2.4.1:

Note: download the zip version of Symfony Standard.

Set-up

I found this framework quite difficult to set-up.

First I had to open the symfony/web/app_dev.php file to comment out this block of code: 

// This check prevents access to debug front controllers that are deployed by accident to production servers.
// Feel free to remove this, extend it, or make something more sophisticated.
/*if (isset($_SERVER['HTTP_CLIENT_IP'])
    || isset($_SERVER['HTTP_X_FORWARDED_FOR'])
    || !in_array(@$_SERVER['REMOTE_ADDR'], array('127.0.0.1', 'fe80::1', '::1'))
) {
    header('HTTP/1.0 403 Forbidden');
    exit('You are not allowed to access this file. Check '.basename(__FILE__).' for more information.');
}*/

And then again in symfony/web/config.php 

/*if (!in_array(@$_SERVER['REMOTE_ADDR'], array(
    '127.0.0.1',
    '::1',
))) {
    header('HTTP/1.0 403 Forbidden');
    exit('This script is only accessible from localhost.');
}*/

Now I can browse to the config.php file, which tells me I need to make the folders app/cache/ and app/logs/ writable by all, which is easy enough.

It also tells me to "set the date.timezone setting in php.ini (like Europe/Paris)". I will ask ITS to make the change at server level, but in the meantime you can specify it in the .htaccess file, by adding this line right at the end of the file: 

php_value date.timezone "Europe/London"

I can now browse to my home page (http://mi-linux.wlv.ac.uk/~in9352/symfony/web/app_dev.php/), but it throws a memory error: 

FatalErrorException: Error: Allowed memory size of 16777216 bytes exhausted (tried to allocate 262144 bytes)

Again we can get around the issue by increasing the amount of RAM PHP can use on the server by adding this line to the .htaccess file: 

php_value memory_limit 64M

But I am a little concerned that this framework seems to require a lot of server resources!

Laravel

Installing Laravel

The Laravel framework utilizes Composer for installation and dependency management, which is not currently installed on mi-linux. Fortunately you can install it in your home folder by running the following commands: 

mkdir ~/bin
wget -O ~/bin/composer https://getcomposer.org/composer.phar
chmod +x ~/bin/composer
echo PATH=\$PATH:\~/bin >>~/.bashrc
. ~/.bashrc

Then you can run the install command as per Quickstart guide instructions: 

composer create-project laravel/laravel your-project-name --prefer-dist

The command above will download and install a fresh copy of Laravel in a new your-project-name folder within your current directory. I want to call my folder "laravel", so I move to public_html, and run the following command: 

composer create-project laravel/laravel laravel --prefer-dist

The installation takes a while. Once finished I shoule be able to browse to the newly created app's public folder: http://mi-linux.wlv.ac.uk/~in9352/laravel/public/index.php

But at first I was getting an HTTP 500 error. This is normally caused by invalid/unsupported commands in the .htaccess file.

I had to REMOVE the following lines from the .htaccess located in laravel/public 

<IfModule mod_negotiation.c>
    Options -MultiViews
</IfModule>

Now I can browse to the welcome page: http://mi-linux.wlv.ac.uk/~in9352/laravel/public/index.php (it should say "You have arrived").

Getting started

Now you can get on with the Quickstart guide (see URL above), for example if I add this "route" to the routes.php file as per instructions: 

Route::get('users', function()
{
    return 'Users!';
});

I can then browse to: http://mi-linux.wlv.ac.uk/~in9352/laravel/public/index.php/users

Ideally we would want to hide the "index.php" in the URL, but we'll worry about this later :)

Zend Framework

So far I have not managed to successfully install Zend on mi-linux :(

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