Includes controller for CodeIgniter (JS and CSS) w/ caching

includes.php

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

/**
 * Includes for CodeIgniter
 *
 * @author gBrock
 *
 * Reads the passed URLs and renders the appropriate CSS and JS files from
 * the application's /views/ folder.  Hopefully self-explanatory.
 *
 * 		BASIC USAGE
 *
 * 		Target /includes/css/file.css and/or /includes/js/file.js in your views, then
 * 		put your renderable files in /application/views/includes/css and /js.
 *
 * 		Make sure your /application/cache/ folder is writable if you want to use
 * 		the filecache (if global ENVIRONMENT is production, by default).
 **/

class Includes extends CI_Controller {

	function __construct()
	{
		parent::__construct();
	}

	// Renders a CSS file to the page.
	//
	// 	EXAMPLE: targetting site_url("includes/css/screen.css") in your HTML would correspond to this function,
	// 	look for "application/views/includes/less" and, if found, pass it to a renderer function render_css() 
	//	(LESS renderer not included), and cache the file using CodeIgniter's file cache (if in production).

	public function css()
	{
		// Where our application's renderable files are located
		$sCSSFolder = 'views/includes/less';

		// our target file
		$sTargetFile = implode('/', array_slice($this->uri->segment_array(), 2));

		// The info about where it is supposed to exist in our filestructure
		$oPath = (object) array_filter(pathinfo($sTargetFile));

		// How long should it be cached? (seconds)
		$iCacheTime = 0;
		
		switch(ENVIRONMENT)
		{
			case 'production':
				$iCacheTime = 60*10; // one hour in production
				break;
		}

		// This page should only serve CSS files
		if(empty($oPath) ||
			empty($oPath->extension) ||
			$oPath->extension !== 'css')
		{
			return show_404();
		}

		// The basic, non-extensioned path.
		$sBasePath = ($oPath->dirname != '.' ? $oPath->dirname.'/' : '').$oPath->filename;

		// The CSS file
		$sCSSPath = $sBasePath.'.css';

		// The source LESS file
		$sRealFile = 
			APPPATH.
			$sCSSFolder.'/'.
			$sBasePath.
			'.less';

		if(!file_exists($sRealFile)) // No file, get out of here
		{
			return show_404();
		}

		///////
		// SERVER CACHING
		//////
		$this->load->driver('cache');

		// The target cache key
		$sCacheKey = str_replace('/', '.', $sCSSPath);


		// If we don't have valid cache data we have to generate it (i.e. RENDER FILE HERE)
		if(!$sOutput = $this->cache->file->get($sCacheKey))
		{
			// Use $sBasePath here to do specific things with different files

			if(file_exists($sRealFile))// If our file exists, render and cache it.
			{
				$sOutput = $this->render_css($sRealFile);

				if($iCacheTime > 0)
				{
					$this->cache->file->save($sCacheKey, $sOutput, $iCacheTime);
				}
			}
		}
		///////

		///////
		// CLIENT CACHING
		//////
		$iSecondsValid = 0;
		switch(ENVIRONMENT) {
			case 'production':
				$iSecondsValid = (60*60*24*7); // one week
				break;
		}

		$this->cache_headers($iSecondsValid, $sRealFile);
		///////
		
		// Output the CSS string
		$this->output
			->set_content_type('css')
			->set_output($sOutput);
	}

	// Renders a JS file to the page.
	//
	// 	EXAMPLE: targetting site_url("includes/css/app.js") in your HTML would correspond to this function,
	// 	look first for "application/views/includes/js/app.js" and then for the same filename but with ".php",
	//	and, if either was found, render it and cache the file using CodeIgniter's file cache (if in production).
	public function js()
	{
		// Where our application's renderable files are located
		$sJSFolder = 'includes/js';

		// our target file
		$sTargetFile = implode('/', array_slice($this->uri->segment_array(), 2));

		// The info about where it is supposed to exist in our filestructure
		$oPath = (object) array_filter(pathinfo($sTargetFile));

		// How long should it be cached? (seconds)
		$iCacheTime = 0;
		switch(ENVIRONMENT) {
			case 'production':
				$iCacheTime = 60*60; // one hour in production
				break;
		}

		// This page should only serve JS files
		if(empty($oPath) ||
			empty($oPath->extension) ||
			$oPath->extension !== 'js')
		{
			return show_404();
		}

		// The basic, non-extensioned path.
		$sBasePath = ($oPath->dirname != '.' ? $oPath->dirname.'/' : '').$oPath->filename;

		// The JS file
		$sJSPath = $sBasePath.'.js';

		// The potential viewfile
		$sViewFile = 
			$sJSFolder.'/'.
			$sJSPath;

		// The potential source JS file
		$sRealFile = 
			APPPATH.
			'views/'.$sViewFile;

		if(!file_exists($sRealFile) && !file_exists(APPPATH.'views/'.$sViewFile.'.php')) // No file
		{
			return show_404();
		}

		// SERVER FILE CACHING
		$this->load->driver('cache');

		// The target cache key
		$sCacheKey = str_replace('/', '.', $sJSPath);

		// If we don't have valid cache data we have to generate it (i.e. RENDER FILE HERE)
		if(!$sOutput = $this->cache->file->get($sCacheKey))
		{
			// Use $sBasePath here to do specific things with different files

			if(file_exists($sRealFile))// If our file exists, render and cache it.
			{
				$sOutput = file_get_contents($sRealFile);
			}
			else
			{
				$sOutput = $this->load->view($sViewFile.'.php', NULL, TRUE);
			}

			if($iCacheTime > 0) {
				$this->cache->file->save($sCacheKey, $sOutput, $iCacheTime);
			}
		}

		// CLIENT CACHING
		$iSecondsValid = 0;	// No cache headers
		switch(ENVIRONMENT) {
			case 'production':
				$iSecondsValid = (60*60*24*7); // one week
				break;
		}
		$this->cache_headers($iSecondsValid, $sRealFile);


		// output as JS.
		$this->output
			->set_content_type('js')
			->set_output($sOutput);
	}

	// Renders a CSS file to a string. Add your favorite LESS / SCSS renderer here.
	private function render_css($sInputFile = '') {
		// By default, no rendering, just get the file contents and spit them back
		$sOutput = file_get_contents($sInputFile);

		return $sOutput;
	}

	// Send the common caching headers.  Optionally include when the file was last modified.
	private function cache_headers($iSeconds, $sFile = FALSE)
	{
		if($iSeconds)
		{
			$sValidUntil = gmdate('D, d M Y H:i:s', time() + $iSeconds) . ' GMT';

			$this->output
				->set_header('Cache-Control: public')
				->set_header('Expires: ' . $sValidUntil);

			if($sFile !== FALSE && file_exists($sFile))
			{
				$sLastModified = gmdate('D, d M Y H:i:s', filemtime($sFile)) . ' GMT';
				$this->output
					->set_header('Last-Modified: ' . $sLastModified);
			}
		}
	}
}

/* End of file includes.php */
/* Location: ./application/controllers/includes.php */