I’ve been spending a lot of time trying to figure out where I can improve the overall speed of web pages and websites in general and it’s come to my attention, that a lot of ColdFusion developers have not worked with some of the new caching capabilities available to us. I believe most of the reason is that their company is still on ColdFusion 8 and hasn’t found a reason or has the capital to upgrade to at least CF9, let alone CF10.

Whether you’re preparing yourself for when you’re working with at least CF9 or maybe you need a quick refresher on some syntax, I’m going to provide a small example that can be used in a number of applications.

For the first part of these blog posts, we’re going to take a look at how to store a query object in Ehcache with ColdFusion 9.

There are three functions in particular you should remember; cacheGet(), cachePut() and cacheRemove(). They’re used exactly how they’re named and their purpose is for accessing the Ehcache layer.

<!--- check for the query object in the cache--->
<cfset getAllMembers = cacheGet("qry-getAllMembers") />
<!--- we're going to set a message just to see what runs --->
<cfset message = "Data came from the cache" />
<!--- check to see if the cache object has any data --->
<cfif isNull(getAllMembers)>
	<!--- query for some data --->
    <cfquery name="getAllMembers" datasource="local_sample">
        SELECT first_name,last_name,email,zip
        FROM member
        LIMIT 30
    </cfquery>
    <!--- insert the query into the cache --->
	<cfset cachePut("qry-getAllMembers",getAllMembers,CreateTimeSpan(0,1,0,0)) />
    <cfset message = "Data came from the query" />
</cfif>
<!--- output the message just to confirm you're retrieveing the data from the correct source--->
<p><cfoutput>#message#</cfoutput></p>
<!--- dump the query object --->
<cfdump var="#getAllMembers#" />

You should see something like this:

When you refresh the page, you should see the exact same thing, only with a different message:

Now there’s going to be times when you need to clear the cache, and that can be easily done by calling cacheRemove(). In this example, I’m just checking for a url variable and and then calling the function so we can requery the data and then recache the new query object.

Let’s take a look at a small piece of code we can add to refresh the cache object:

<!--- check for the url.resetcache variable to clear the current cache object --->
<cfif StructKeyExists(url,"resetcache")>
	<cfset cacheRemove("qry-getAllMembers") />
</cfif>

Now if we put it all together, we’ve got:

<!--- check for the url.resetcache variable to clear the current cache object --->
<cfif StructKeyExists(url,"resetcache")>
	<cfset cacheRemove("qry-getAllMembers") />
</cfif>

<!--- check for the query object in the cache--->
<cfset getAllMembers = cacheGet("qry-getAllMembers") />
<!--- we're going to set a message just to see what runs --->
<cfset message = "Data came from the cache" />
<!--- check to see if the cache object has any data --->
<cfif isNull(getAllMembers)>
	<!--- query for some data --->
    <cfquery name="getAllMembers" datasource="local_sample">
        SELECT first_name,last_name,email,zip
        FROM member
        LIMIT 15
    </cfquery>
    <!--- insert the query into the cache --->
	<cfset cachePut("qry-getAllMembers",getAllMembers,CreateTimeSpan(0,1,0,0)) />
    <cfset message = "Data came from the query" />
</cfif>
<!--- output the message just to confirm you're retrieveing the data from the correct source--->
<p><cfoutput>#message#</cfoutput></p>
<!--- dump the query object --->
<cfdump var="#getAllMembers#" />

Just a couple of notes to end the post:

1. Caching isn’t meant for everything, you should first figure out if the application would benefit from it in the first place.
2. You can easily use to clear the specific cache on multiple servers, so don’t be afraid of caching dynamic pages throughout multiple servers.
3. You’re not going to run out of caching memory, but always refer to the first note.
4. Fact: The faster the website, the greater the conversion rate.

I’m not going to throw up a demo because there’s really nothing to look at, but I’ll provide the code with the database dump of a large sample table for you to do some testing with.

Tags: caching, coldfusion, ehcache, website optimization

Posted in ColdFusion
No Comments Yet Posted by Michael Stone