2.3.2releasedCacheable Datasource

Improve page performance by caching data source output XML.

Clone URLhttps://github.com/symphonists/cacheabledatasource.git

Add as a submodulegit submodule add https://github.com/symphonists/cacheabledatasource.git extensions/cacheabledatasource --recursive

Compatibility

2.x.x2.1.x2.2.x2.3.x2.4.x2.5.x2.6.x2.7.0
NoNo1.0.01.1.12.1.1No2.3.22.3.2

Readme

Cacheable Datasource

Some datasources simply execute a lot of database queries. It's a fact of life, so instead of complaining, learn to deal with it ;-) You can:

  • reduce the number of fields and entries that the datasource is fetching
  • use the Cachelite extension to cache the entire rendered HTML output of pages (useful to survive big traffic spikes)

However sometimes neither of these are viable options. Perhaps you really need all of that data in your XML all of the time, or perhaps you have a "Logged in as {user}" notice in the header that means you can't cache the HTML output of the page for all users.

This extension enables datasources that fetch entries from sections to be cached — their XML result is stored in your server until the timeout expires, meaning fewer calls to your database and hopefully more pages served, faster.

(The idea stemmed from explorations in a forum discussion Datasource Caching.)

Usage

Install this extension like any other. When you create or edit a datasource that fetches entries from a section, you will see an additional "Cache" option at the bottom of the editor. Change the number of seconds to suit your requirement. A value of 0 means no caching.

Refresh your frontend page

View the ?debug XML of your frontend page and you should see the cached XML and the age of the cache in seconds. The cached XML might jump to the top of the order in the XML source. This is normal, and is a by-product of how Symphony works out ordering on the fly.

The first time you execute the datasource you will see the data marked as fresh. This has come directly from the database as usual:

xml <my-data-source cache-age="fresh">

Subsequent refreshes will show you the age of the cached data in seconds:

xml <my-data-source cache-age="30s">

Frequently Asked Questions

Are Output Parameters supported?

Yes! If a datasource outputs parameters into the param pool then these are cached along with the XML.

How do I purge the cache?

Caches expire when their timeouts are met. You can manually purge the cache by looking into your /manifest/cache/cacheabledatasource folder and deleting files with names beginning with the name of your datasource.

Why are so many cache files created?

Cache files are never deleted, only overwritten when they have expired. It is normal to have many files generated for each datasource since the filename is a hashed signature of all of its configuration properties and filters. This means that if you have pagination enabled on your datasource, a new cache file is generated for each page of results, since each page creates a unique combination of filters (and therefore unique XML).

How do I cache custom data sources?

Just add the $dsParamCACHE variable to specify the cache lifetime and make sure that all dynamic values are added to $dsParamFILTERS array. Page parameters are evaluated automatically, e. g. {$current-page}, {$url-filter} will be replaced by their actual values before creating the cache file (note the curly braces).

Version history

Symphony 2.6.0 to 2.x.x

  • Fix regression with ignored data sources (#22)

Symphony 2.6.0 to 2.x.x

  • Fix wrong label which is in seconds, not minutes (#22)
  • Fix potential remote code execution vector

Symphony 2.6.0 to 2.x.x

  • Fix issue with associated sections (#12)
  • Prevent double caching when the data source is a remote or dynamic data source
  • Add support for frontend_localisation and multilingual fields

Requires Symphony 2.6

  • Fix parameter pool handling (#14)
  • Fix datasource filter storage (#17)
  • Clean-up

Requires Symphony 2.4

  • Improved and updated documentation in readme file

Requires Symphony 2.4

  • Added cache folder creation, if missing

Requires Symphony 2.4

  • Symphony 2.4 compatibility

Requires Symphony 2.3

Requires Symphony 2.3

Symphony 2.2 to 2.2.5

  • major milestone release
  • removed unnecessary bloat of the Cache Viewer page
  • cache files are now stored in a folder within the cache directory for easier bulk purging
  • no more editing of data sources! Caching is applied unobtrusively with delegates and JavaScript (Symphony 2.3+) meaning you don't need to touch PHP and customise your data source files
  • fixed a major bug whereby the extension would not escape invalid XML properly