// $Id$ BOOST MODULE FOR DRUPAL 6.x --------------------------- CONTENTS OF THIS README ----------------------- * Description * Features * Requirements * Recommended Modules * Installation * System Check & Verify Functions * Boost Administrative and Stats Blocks * Configuration Tips * Important Notes & Troubleshooting * File System Cache * How Boost Works * Dispatch Mechanism * Limitations * Boost Handbook Links * Boost Project & Drupal Links * Credits DESCRIPTION ----------- This module provides static page caching for Drupal 6.x websites. It provides a significant performance increase as well as scalability for sites that receive mostly anonymous traffic. Web pages load very fast from the cache instead of waiting on PHP and Drupal to serve them from the database. If the page is not found in the cache, then the request is passed to Drupal. The built-in crawler makes sure expired content is quickly regenerated to insure fast page loading at all times. The guy that is writing this could brag about Boost, but he will let you do that part. Enjoy! FEATURES -------- *** This is a partial list, because it could take the whole page. * Fast page serving for anonymous visitors to your Drupal website. * Reduces web server load and increases your site's scalability. * On-demand page caching (static file created after first page request). * Uses cron run to trigger cleaning of cached files. * Built in crawler to automatically regenerate cached files. * Adjustable cache lifetimes for different parts of the website. * Supports HTML, XML, CSS, JavaScript, JSON/AJAX. * Injects HTML comment to provide easy verification of Boost. * Supports shared, VPS and dedicated hosting. * Supports sub-directory Installations. * Full support for multi-site Drupal installations. REQUIREMENTS ------------ Boost is designed for Drupal 6.x served by Apache on any platform. Drupal's clean URLs MUST be enabled and working properly. If the cached files and pages must be cleared at their expired time, the cron run for Drupal must be correctly setup to execute more often than, or as often as the cache lifetime you specify in the settings. Since the static page caching is implemented with mod_rewrite directives, Apache version 1.3 or 2.x with mod_rewrite enabled is required (if Drupal's clean URLs work for you, you're fine; if not, get them working first). Other web servers, such as Lighttpd, are NOT officially supported at present. Lighttpd: http://drupal.org/node/150909 Nginx: http://drupal.org/node/244072 RECOMMENDED MODULES ------------------- Path (Drupal Core) Global Redirect http://drupal.org/project/globalredirect Transliteration http://drupal.org/project/transliteration Pathauto http://drupal.org/project/pathauto Token http://drupal.org/project/token Optional if cron configuration is not available on your server. Poormanscron -dev http://drupal.org/project/poormanscron If enabled [x] Clear all cached pages referenced via CCK with a node... The node referrer module is recommended. Node Referrer http://drupal.org/project/nodereferrer INSTALLATION ------------ 1. Goto: [Administer > Site configuration > Clean URLs] and ensure that Drupal's clean URLs are enabled and working correctly on your site. 2. Unzip and upload the module folder (as is) to the sites/all/modules folder in your Drupal installation directory. 3. Goto: [Administer > Site building > Modules] and enable the Boost module. You will find it in the section labeled "Caching". 4. Goto: [Administer > Site configuration > Performance > Boost settings] Specify the cache directory, which should be something like cache/normal/www.example.com (keeping the default directory is recommended) and must be writeable by the web server: you may need to create the directory, and set the permissions so it is writeable. On the [Administer > Site configuration > Performance > Boost settings] page is the Default maximum cache lifetime setting. As cached pages are created, they are given an expire by date and time, which is the current date and time plus the maximum cache lifetime. These dates and times are checked on each cron run; and if a page is expired, the cache is cleared, and a new cached version will be created the next time the page is called upon by an anonymous user (including bots). The page will be regenerated by the Boost crawler if enabled on the Boost settings page. 5. IMPORTANT: --- This step is easy and required for Boost to work! --- Back up the original .htaccess file from your Drupal installation directory for safe keeping. Copy the custom generated htaccess rule from [Administer > Site configuration > Performance > htaccess rules generation] page and paste the rules into the Drupal htaccess file as shown below. # RewriteBase / -------paste the rules right here-------- # Rewrite URLs of the form 'x' to the form 'index.php?q=x'. In the boost/htaccess/ folder, the default.txt file shows you the exact placement of the rules, in case your not sure. The module package has 3 htaccess templates included in the Boost/htaccess folder (boosted1.txt, boosted2.txt and default.txt). These templates may be helpful in some cases and are good for reference. For the technically inclined, the difference between the two .htaccess templates is due to boosted1.txt relying on SERVER_NAME versus boosted2.txt using HTTP_HOST. There are valid use cases for both in more advanced multi-site installations. 6. Goto: [Administer > Site configuration > Performance] Check and set the Drupal cache settings as desired. SYSTEM CHECK AND VERIFY FUNCTIONS --------------------------------- 1. Log out from Drupal (or use another browser) to browse around your site as the anonymous user. Ensure that static files are indeed being generated into the Boost cache directory you specified above (#4); and if you opt to use gzip, likewise check gzipped files are being generated in the directory you specified for this. The Administer > Performance > Boost settings page shows how many pages are cached by Boost. 2. Check the Drupal status page [Administer > Reports > Status report] for any errors or notices. 3. To check whether you have a cached or dynamic version of a page, look at the very end of the page's HTML source. You have the cached version if the last line looks like this: BOOST ADMINISTRATIVE AND STATS BLOCKS ------------------------------------- There are 2 blocks that you can add to help with the administrative side (status, page configuration), and 1 block to support core stats. Goto: (administer > Site building > Blocks > List) to place them. The visibility of blocks can also be configured by role and page. On the Blocks list page, to the right of each block click 'configure'. * Status Block This block shows the current status of the page as far as Boost is concerned. It will state if the page is served 'live' or by 'Boost', the expiration of the page and has a Flush Page button to clear the page from the cache manually. The block only appears if your not user 0 and provides useful information about PHP errors on the page. * Page configuration Block This block allows the administrator to set pages individually. Including setting for maximum cache lifetime(select box), preemptive cache(on or off), scope(page ID, content type or content container). * Stats Block Drupal's core stats is supported. Configure the "Popular content" block, but then disable it. Place the "Boost: AJAX core statistics" in its place. If ajax stats are loading too slowly, copy stats/boost_stats.php to your webroot and enable "Cache Statistics Block". The cache gets updated on cron runs. CONFIGURATION TIPS ------------------ For the (i18n) and the (Domain) modules: Enable [x] Do not store the cache file path in the database [x] Flush all sites caches in this database (singe db, multi-site) Disable [ ] Only allow ASCII characters in path Enable XML & AJAX/JSON caches Enable [x] Cache .xml & /feed [x] Cache ajax/json To Use the Cron Crawler Enable [x] Overwrite the cached file if it already exits [x] Expire content in DB, do not flush file. [x] Enable the cron crawler IMPORTANT NOTES AND TROUBLESHOOTING ----------------------------------- * If cron is not clearing the cache as expected. Set $base_url variable in /sites/default/settings.php (line 125 or so) so cron runs error free and clears the cache properly when invoked like 'php /path/to/cron.php' or 'drush cron'. This should be something like http://www.example.com Guide for editing settings.php http://drupal.org/node/367081#comment-1504894 * If your Drupal URL paths contain non-ASCII characters, you may have to tweak your locate settings on the server in order to ensure the URL paths get correctly translated into directory paths in the file system. You can also turn off the ASCII filter in the Boost Advanced Settings. OR install the Transliteration module to help fix the characters. FILE SYSTEM CACHE ----------------- The cached files are stored (by default) in the cache/normal/ directory under your Drupal installation directory. The Drupal pages' URL paths are translated into file system names in the following manner: http://example.com/ => cache/normal/example.com/_.html http://example.com/about => cache/normal/example.com/about_.html http://example.com/about/staff => cache/normal/example.com/about/staff_.html http://example.com/node/42 => cache/normal/example.com/node/42_.html You'll note that the directory path includes the Drupal site name, enabling support for multi-site Drupal installations. HOW BOOST WORKS --------------- Once Boost has been installed and enabled, page requests by anonymous visitors will be cached as static HTML pages in the server's file system. Periodically (when the Drupal cron runs) stale or expired pages (i.e. files or pages exceeding the maximum cache lifetime setting) will be purged, allowing them to be recreated the first time that the next anonymous visitor requests that page again. If the Cron Crawler is enabled, the files and pages will be regenerated automatically. New rewrite rules are added to the .htaccess file supplied with Drupal, directing the web server to try and fulfill page requests by anonymous visitors first and foremost from the static page cache, and to only pass the request through to Drupal if the requested page is not cacheable or hasn't yet been cached. DISPATCH MECHANISM ------------------ For each incoming page request, the new Apache mod_rewrite directives in .htaccess will check if a cached version of the requested page should be served as per the following simple rules: 1. First, we check that the HTTP request method being used is GET. POST requests are not cacheable, and are passed through to Drupal. 2. Since only anonymous visitors can benefit from the static page cache at present, we check that the page request doesn't include a cookie that is set when a user logs in to the Drupal site. If the cookie is present, we simply let Drupal handle the page request dynamically. 3. Now, for the important bit: we check whether we actually have a cached HTML file for the request URL path available in the file system cache. If we do, we direct the web server to serve that file directly and to terminate the request immediately after; in this case, Drupal (and indeed PHP) is never invoked, meaning the page request will be served by the web server itself at full speed. 4. If, however, we couldn't locate a cached version of the page, we just pass the request on to Drupal, which will serve it dynamically in the normal manner. LIMITATIONS ----------- * Only anonymous visitors will be served cached versions of pages; authenticated users will get dynamic content. This will limit the usefulness of this module for those community sites that require user registration and login for active participation. * In contrast to Drupal's built-in caching, static caching will lose any additional HTTP headers set for an HTML page by a module. This is unlikely to be problem except for some very specific modules and rare use cases. * Web server software other than Apache is not supported at the moment. Adding Lighttpd support would be desirable but is not a high priority for the developer at present (see TODO.txt). (Note that while the LiteSpeed web server has not been specifically tested by the developer, it may, in fact, work, since they claim to support .htaccess files and to have mod_rewrite compatibility. Feedback on this would be appreciated.) HANDBOOK PAGES -------------- Boost handbook http://drupal.org/node/545664 Installation & Settings http://drupal.org/node/545908 Boost Tips & Tricks http://drupal.org/node/583264 FAQ & Future Features http://drupal.org/node/546134 Using & Blogging About Boost http://drupal.org/node/546834 BOOST PROJECT & DRUPAL LINKS ---------------------------- Boost project page http://drupal.org/project/boost ** Post feature requests and bug reports: Boost issue que http://drupal.org/project/issues/boost ** The Drupal 'post installation' forum: Drupal Help Forum http://drupal.org/forum/22 ** The original blog post about Boost: http://bendiken.net/2006/05/28/static-page-caching-for-drupal CREDITS ------- Originally Developed by Arto Bendiken(arto) http://bendiken.net Ported to Drupal 5.x by Alexander I. Grafov(axel) http://drupal.ru Ported to Drupal 6.x by Ben Lavender(bhuga) http://bhuga.net Miscellaneous contributions by Jacob Peddicord, Justin Miller & Barry Jaspan. 6.x Developer and Maintainer, Mike Carper(mikeytown2) of http://316solutions.net END OF FILE -----------