Programming ColdFusion MX, 2nd Edition

Name

cfcache

Synopsis

<cfcache>

Caches a ColdFusion page for faster access by writing a temporary static HTML version of the page to disk (either server-side or in the client’s browser cache, or both). To cache a ColdFusion template, just add the cfcache tag to the top of the page.

When the cfcache tag caches a page, two files are actually written to the server. First, a temporary file (with a .tmp extension) is created that contains the HTML necessary to generate the static version of the page. A mapping file contains the mapping to the temp file, as well as a timestamp that determines when to expire the cached file. The name for the mapping file is determined by appending the hash of the current URL (see Hash( ) in Appendix B) to cfcache_. This results in filenames like this: cfcache_D6BF3A60769FD03FE598BB2E8490CB11.tmp. When using the cfcache tag, there are a few additional points that should be considered:

• Templates that generate errors don’t get cached.

• Pages generating personalized content should be cached on the client only (action="ClientCache") to avoid serving the cached content to people who are not intended to see it.

• By default, the cfcache tag suppresses all debugging information for a ColdFusion template. To use debugging within a cached page, you must explicitly turn it on for the template using the cfsetting tag.

• Simultaneous Requests in the ColdFusion Administrator must be set to a minimum of 2 for the cfcache tag to work.

• In ColdFusion MX, it’s now possible to ...