Run Code Igniter on H2 database engine using PDO and Quercus

In my previous post I explained how to setup PHP and H2 database engine using a platform-independent Java stack, a.k.a. JAMP. I managed to get the Code Igniter framework running on JAMP, with some tweaking of the Code Igniter PDO driver. Here are the steps to make it work.

If you would like to skip these steps and jump immediately into some coding action, download the demo.
(Unzip and go into directory jamp-ci-demo/, then type `mvn jetty:run` from the command line. You need Maven installed to execute this command.)

jamp-ci-demo.zip
File Size:	2341 kb
File Type:	zip

Download File

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First, checkout a copy of JAMP at github (git clone https://github.com/webdevelopersdiary/jamp.git).

Then download Code Igniter and put in the web root (src/main/webapp/).

Because Code Igniter likes pretty urls (ie. /controller_name/method_name) I added support for mod_rewrite to JAMP. It can parse mod_rewrite rules which are located in .htaccess directly in the web root (src/main/webapp/). Add src/main/webbapp/.htaccess with mod_rewrite rules:

<IfModule mod_rewrite.c>
 	RewriteEngine On
 
 	RewriteCond %{REQUEST_URI} ^(system|application).*
 	RewriteRule ^(.*)$ /index.php?/$1 [L]
 
 	RewriteCond %{REQUEST_FILENAME} !-f
 	RewriteCond %{REQUEST_FILENAME} !-d
 	RewriteRule ^(.*)$ index.php?/$1 [L]
 </IfModule>
 
 <IfModule !mod_rewrite.c>
 	ErrorDocument 404 /index.php
 </IfModule>

Start up the JAMP web server (make sure .htaccess exists before starting the web server or it will have trouble discovering it, then execute mvn jetty:run). Verify Code Igniter is running correctly by going to http://localhost:8080/welcome (the default controller).

If you see a pesky error '$assign_to_config is an undefined variable', go to src/main/webapp/index.php and add

$assign_to_config = array();

under the section 'CUSTOM CONFIG VALUES' (line 110 of index.php) and that should get rid of the error.

Next we configure Code Igniter to connect to the H2 database using PDO. Edit the configuration located at src/main/webapp/application/config/database.php and set these settings:

$db['default']['hostname'] = 'mysql:';
 $db['default']['dbdriver'] = 'pdo';

Next, we have to make a slight modification to Code Igniter's PDO driver. Change the method num_rows() from src/main/webapp/system/database/drivers/pdo/pdo_result.php to:

	/**
 	 * Number of rows in the result set
 	 *
 	 * @access	public
 	 * @return	integer
 	 */
 	function num_rows()
 	{
 		$sql = $this->result_id->queryString;
 		if(NULL === $sql) {
 			$sql = print_r($this->result_id, TRUE);
 			$quercus_preg = '/\Aresource\(PDOStatement\[(.*)\]\)\z/is';
 			$php_preg = '/\APDOStatement Object\s*\(.*=>\s*(.*)\)\s*\z/is';
 			if(preg_match($quercus_preg, $sql)) {
 				// We're running in Quercus
 				$sql = preg_replace($quercus_preg, '\1', $sql);
 			} else if(preg_match($php_preg, $sql)) {
 				// We're running in PHP
 				$sql = trim(preg_replace($php_preg, '\1', $sql));
 			} else {
 				// No clue about what is running this script!
 				$sql = NULL;
 			}
 		}
 		if (is_numeric(stripos($sql, 'SELECT')))
 		{
 			$count = count($this->result_id->fetchAll());
 			$this->result_id->execute();
 			return $count;
 		}
 		else
 		{
 			return $this->result_id->rowCount();
 		}
 	}

Everything should now be in place to connect to the H2 database using Code Igniter's ActiveRecord library. Let's test it! Create a test controller application/controller/test.php:

<?php
 
 class Test extends CI_Controller {
 	public function index() {
 		$this->load->database();
 		$sql = $this->db->query('CREATE TABLE IF NOT EXISTS test (value DATETIME)');
 		$sql = $this->db->set('value', 'NOW()', FALSE)->insert('test');
 		var_dump($this->db->get('test')->result());
 	}
 }

Voila! Go to http://localhost:8080/test and enjoy a working Code Igniter on H2 database using ActiveRecord :-)

Note: I used Code Igniter version 2.1.2, Quercus version 4.0.28 and H2 database version 1.3.167.