jcn/drupal-boost
My own modifications of the Boost Drupal module. You probably don't want to use these at all.
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DESCRIPTION
This module provides static page caching for Drupal 5.x, enabling a
potentially very significant performance and scalability boost for
heavily-trafficked Drupal sites.
For an introduction, read the original blog post at:
http://bendiken.net/2006/05/28/static-page-caching-for-drupal
FEATURES
- Maximally fast page serving for the anonymous visitors to your Drupal
site, reducing web server load and boosting your site's scalability. - On-demand page caching (static file created after first page request).
- Full support for multi-site Drupal installations.
INSTALLATION
Please refer to the accompanying file INSTALL.txt for installation
requirements and instructions.
HOW IT WORKS
Once Boost has been installed and enabled, page requests by anonymous
visitors will be cached as static HTML pages on the server's file system.
Periodically (when the Drupal cron job runs) stale pages (i.e. files
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.
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, hasn't yet
been cached, or the cached copy is stale.
FILE SYSTEM CACHE
The cached files are stored (by default) in the cache/ directory under your
Drupal installation directory. The Drupal pages' URL paths are translated
into file system names in the following manner:
http://mysite.com/
=> cache/mysite.com/0/index.html
http://mysite.com/about
=> cache/mysite.com/0/about.html
http://mysite.com/about/staff
=> cache/mysite.com/0/about/staff.html
http://mysite.com/node/42
=> cache/mysite.com/0/node/42.html
You'll note that the directory path includes the Drupal site name, enabling
support for multi-site Drupal installations. The zero that follows, on the
other hand, denotes the user ID the content has been cached for -- in this
case the anonymous user (which is the default, and only, choice available
for the time being).
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:
-
First, we check that the HTTP request method being used is GET.
POST requests are not cacheable, and are passed through to Drupal. -
Next, we make sure that the URL doesn't contain a query string (i.e.
the part after the?' character, such as?q=cats+and+dogs'). A query
string implies dynamic data, and any request that contains one will
be passed through to Drupal. (This also allows one to easily obtain the
current, non-cached version of a page by simply adding a bogus query
string to a URL path -- very useful for testing purposes.) -
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. -
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. -
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.
IMPORTANT NOTES
- Drupal URL aliases get written out to disk as relative symbolic links
pointing to the file representing the internal Drupal URL path. For this
to work correctly with Apache, ensure your .htaccess file contains the
following line (as it will by default if you've installed the file shipped
with Boost):
Options +FollowSymLinks - To check whether you got a static or dynamic version of a page, look at
the very end of the page's HTML source. You have the static version if the
last line looks like this: - 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 on the file system.
Non-ASCII URL paths have currently not been tested at all and feedback on
them would be appreciated.
LIMITATIONS
- Only anonymous visitors will be served cached versions of pages; logged-in
users will get dynamic content. This may somewhat limit the usefulness of
this module for those community sites that require user registration and
login for active participation. - Only content of the type `text/html' will get cached at present. RSS feeds
and URL paths that have some other content type (e.g. set by a third-party
module) will be silently ignored by Boost. - 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 author at present (see TODO.txt). (Note that while the LiteSpeed web
server has not been specifically tested by the author, it may, in fact,
work, since they claim to support .htaccess files and to have mod_rewrite
compatibility. Feedback on this would be appreciated.) - At the moment, Windows users are S.O.L. due to the use of symlinks and
Unix-specific shell commands. The author has no personal interest in
supporting Windows but will accept well-documented, non-detrimental
patches to that effect (see http://drupal.org/node/174380).
BUG REPORTS
Post feature requests and bug reports to the issue tracking system at:
http://drupal.org/node/add/project_issue/boost
CREDITS
Developed and maintained by Arto Bendiken http://bendiken.net/
Ported to Drupal 5.x by Alexander I. Grafov http://drupal.ru/
Miscellaneous contributions by: Jacob Peddicord, Justin Miller, Barry
Jaspan.