Merge pull request #34 from green-ponies/master

CSS & JS caching and Fix for Issue 22

core/imageboard.pack.php

@@ -93,6 +93,7 @@ class Image {
 	public static function by_random($tags=array()) {
 		assert(is_array($tags));
 		$max = Image::count_images($tags);
+		if ($max < 1) return null;		// From Issue #22 - opened by HungryFeline on May 30, 2011.
 		$rand = mt_rand(0, $max-1);
 		$set = Image::find_images($rand, 1, $tags);
 		if(count($set) > 0) return $set[0];

core/page.class.php

@@ -167,8 +167,8 @@ class Page {
 	public function display() {
 		global $page;
 		
-		$this->add_http_header("Content-type: {$this->type}", 1);
+		header("Content-type: ".$this->type);
-		$this->add_http_header("X-Powered-By: SCore-".SCORE_VERSION, 2);
+		header("X-Powered-By: SCore-".SCORE_VERSION);
 
 		if (!headers_sent()) {
 			foreach($this->http_headers as $head){ header($head); }
@@ -204,25 +204,128 @@ class Page {
 	protected function add_auto_html_headers() {
 		$data_href = get_base_href();
 		
-		foreach(glob("lib/*.css") as $css) {
+		/* Attempt to cache the CSS & JavaScript files */
-			$this->add_html_header("<link rel='stylesheet' href='$data_href/$css' type='text/css'>");
+		if ($this->add_cached_auto_html_headers() === FALSE) {
+			// caching failed, add all files to html_headers.
+			
+			foreach(glob("lib/*.css") as $css) {
+				$this->add_html_header("<link rel='stylesheet' href='$data_href/$css' type='text/css'>");
+			}
+			$css_files = glob("ext/*/style.css");
+			if($css_files) {
+				foreach($css_files as $css_file) {
+					$this->add_html_header("<link rel='stylesheet' href='$data_href/$css_file' type='text/css'>");
+				}
+			}
+			
+			foreach(glob("lib/*.js") as $js) {
+				$this->add_html_header("<script src='$data_href/$js' type='text/javascript'></script>");
+			}
+			$js_files = glob("ext/*/script.js");
+			if($js_files) {
+				foreach($js_files as $js_file) {
+					$this->add_html_header("<script src='$data_href/$js_file' type='text/javascript'></script>");
+				}
+			}
 		}
-		$css_files = glob("ext/*/style.css");
+	}
-		if($css_files) {
+
-			foreach($css_files as $css_file) {
+	/*
-				$this->add_html_header("<link rel='stylesheet' href='$data_href/$css_file' type='text/css'>");
+		This function caches the CSS and JavaScript files.
+		This is done to reduce the number of HTTP requests (recommended by
+		the Yahoo high-performance guidelines). It combines all of the CSS
+		and JavaScript files into one for each type, and stores them in 
+		cached files to serve the client. Changes to the CSS or JavaScript
+		files are caught by taking the md5sum of the concatenated files.
+	*/
+	private function add_cached_auto_html_headers()
+	{
+		$cache_location = 'data/cache/';
+		$data_href = get_base_href();
+		
+		if(!file_exists($cache_location)) {
+			if (!mkdir($cache_location, 0750, true)) {
+				return false; // failed to create directory
 			}
 		}
 
-		foreach(glob("lib/*.js") as $js) {
+		/* ----- CSS Files ----- */
-			$this->add_html_header("<script src='$data_href/$js' type='text/javascript'></script>");
+		// First get all the CSS from the lib directory
+		$data_1 = '';
+		$css_files = glob("lib/*.css");
+		if($css_files) {
+			foreach($css_files as $css_file) {
+				$data_1 .= file_get_contents($css_file);
+			}
+			//	Can't directly cache the CSS files, as they might have relative locations to images, etc. in them.
+			//	We have to adjust the URLs accordingly before saving the cached file.
+			$pattern = '/url[\s]*\([\s]*["\']?([^"\'\)]+)["\']?[\s]*\)/';
+			$replace = 'url("../../lib/${1}")';
+			$data_1 = preg_replace($pattern, $replace, $data_1);
+		}
+		// Next get all the CSS from the extensions
+		$data_2 = '';
+		$css_files = glob("ext/*/style.css");
+		if($css_files) {
+			foreach($css_files as $css_file) {
+				$data_2 .= file_get_contents($css_file);
+			}
+			//	Can't directly cache the CSS files, as they might have relative locations to images, etc. in them.
+			//	We have to adjust the URLs accordingly before saving the cached file.
+			$pattern = '/url[\s]*\([\s]*["\']?([^"\'\)]+)["\']?[\s]*\)/';
+			$replace = 'url("../../${1}")';
+			$data_2 = preg_replace($pattern, $replace, $data_2);
+		}
+		// Combine the two
+		$data = $data_1 . $data_2;
+		// compute the MD5 sum of the concatenated CSS files
+		$md5sum = md5($data);
+		
+		if (!file_exists($cache_location.$md5sum.'.css')) {
+			// remove any old cached CSS files.
+			$mask = '*.css';
+			array_map( 'unlink', glob( $mask ) );
+		
+			// output the combined file
+			if (file_put_contents($cache_location.$md5sum.'.css', $data, LOCK_EX) === FALSE) {
+				return false;
+			}
+		}
+		// tell the client where to get the css cache file
+		$this->add_html_header('<link rel="stylesheet" href="'.$data_href.'/'.$cache_location.$md5sum.'.css'.'" type="text/css">');
+
+		
+		/* ----- JavaScript Files ----- */
+		$data = '';
+		$js_files = glob("lib/*.js");
+		if($js_files) {
+			foreach($js_files as $js_file) {
+				$data .= file_get_contents($js_file);
+			}
 		}
 		$js_files = glob("ext/*/script.js");
 		if($js_files) {
 			foreach($js_files as $js_file) {
-				$this->add_html_header("<script src='$data_href/$js_file' type='text/javascript'></script>");
+				$data .= file_get_contents($js_file);
 			}
 		}
+		// compute the MD5 sum of the concatenated JavaScript files
+		$md5sum = md5($data);
+		
+		if (!file_exists($cache_location.$md5sum.'.js')) {
+			// remove any old cached js files.
+			$mask = '*.js';
+			array_map( 'unlink', glob( $mask ) );
+			// output the combined file
+			if (file_put_contents($cache_location.$md5sum.'.js', $data, LOCK_EX) === FALSE) {
+				return false;
+			}
+		}
+		// tell the client where to get the js cache file
+		$this->add_html_header('<script src="'.$data_href.'/'.$cache_location.$md5sum.'.js'.'" type="text/javascript"></script>');
+		
+		return true;
 	}
+
 }
 ?>