[TUTORIAL] Using Caching to Speed Up Your Code

[mjaz]

Hi,

I wrote a very basic quickstart tutorial on caching functions in 1.5. Feel free to edit it, rewrite it, publish it in the wiki, tattoo it on your forehead, or ignore it


EDIT: removed attachment. Read it at http://dev.joomla.org/component/option, ... g_caching/

[Chris Davenport]

Hi mjaz,

Excellent work Mathias.  This is just the kind of material we need right now.  I'll get it edited, formatted and posted on the dev wiki shortly.

In the meantime a big thank you and please feel free to write some more. 

Regards,
Chris.

[Jinx]

Keep in mind that the whole caching layer is still in WIP and is slated to undergo a refactoring (it's the last major part of the architecture we still need to deal with). We hope to start on it soonish, probably end of next week.

Good work nevertheless, especialy the profiler stuff is fixed and will not change so this can be documented already.

[mjaz]

I needed caching for an extension i'm making. I couldn't find any docs, so I decided to document my progress as I discovered how it works. Didn't know it was still WIP. If the api changes, let us know.

btw Respect to the doc people  :-* , I never imagined writing even such a basic tut could be such hard work. I'll see if I can write some more, no promises though.

[Chris Davenport]

I never imagined writing even such a basic tut could be such hard work.

"What's easy reading is damned hard writing."  G. K. Chesterton (if memory serves) 

@Johan.  Thanks for the warning, I'd forgotten about that.  I'll post it on the dev wiki anyway, but I'll include a prominent health warning too.

Regards,
Chris.

[Chris Davenport]

http://dev.joomla.org/component/option, ... g_caching/

[Jinx]

Thanks guys ! Good team work I call this one.

[mjaz]

After a quick look at the changes in svn, this should be changed in the tutorial:

1. The profiler apparently is not available by default, so all code should have:

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jimport( 'joomla.utilities.profiler' );

2. cleanCache() is now clean():

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$cache->clean();

instead of

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$cache->cleanCache();

3. When getting a reference to the cache object, it will default to 'output', but we need 'callback', so:

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// Get a reference to the global cache object.
$cache = & JFactory::getCache( 'callback' );

4. call() is a wrapper for get(), so we'll use:

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$rows  = $cache->get( array( 'TestClass', 'testMethod' ), $table );

The complete code in part 5 of the tut now looks like this:

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<?php
jimport( 'joomla.utilities.profiler' );

class TestClass {

    function testMethod( $table ) {

        // Get a reference to the global database object.
        $db = & JFactory::getDBO();

        // Execute the same database query 250 times.
        for( $i=0; $i<250; $i++) {
            $db->setQuery( "SELECT * FROM #__$table" );
            $rows = $db->loadObjectList();
        }

        return $rows;
    }
}

// Determine which database table to query.
$table = JRequest::getVar( 'table', 'content' );

// Get a reference to the global cache object.
$cache = & JFactory::getCache('callback' );

// Run the test without caching.
$profiler = new JProfiler();
$rows = TestClass::testMethod( $table );
echo $profiler->mark( ' without caching' );

// Run the test with caching.
$profiler = new JProfiler();
$rows  = $cache->get( array( 'TestClass', 'testMethod' ), $table );
echo $profiler->mark( ' with caching' );
?>

The other code examples should be changed as well.

I'll keep an eye out for any further changes to the svn.

[Chris Davenport]

Hi mjaz,

Rather than update the wiki right now I think I'll wait until we can be certain that the refactoring of the cache code has been completed.  Last I heard it was still work in progress.

Thanks for the update Mathias.

Regards,
Chris.

[Jinx]

It still is indeed, while the code is roughly done we still need to implement it and this usualy goes with some refactoring.

[mjaz]

Ok. Maybe you can add backlink to this thread in the wiki.

[Chris Davenport]

Good idea.  Done.

Regards,
Chris.

[markuz]

It still is indeed, while the code is roughly done we still need to implement it and this usualy goes with some refactoring.

Jinx,

What is the status of the code regarding to caching? I'm exploring the possibilities for my component.

I'm facing several issues like: pathway building problems, registration of 'hits', JToolbarHelper doesn't get called in the backend, etc. etc. Are these issues to be solved, or is it simply not covered by the cache layer?

Thanks in advance,
Mark

[Joombla]

I'm with Markuz, before I go digging around too much with this, does the article stand correct, or is the cache completely refactored and invalidates this article?

Todd

[torkil]

Same question.

[torkil]

I forgot to say that I got a response to this: The cache code is done.

[markuz]

Thanks Torkil,

Still have the following issues though...

I'm facing several issues like: pathway building problems, registration of 'hits', JToolbarHelper doesn't get called in the backend, etc. etc. Are these issues to be solved, or is it simply not covered by the cache layer?

Mark

[AmyStephen]

The wiki points to this thread - and this thread points to the wiki - as the most current documentation. Following is from the wiki.

Warning: The Joomla! 1.5 cache API is currently being refactored and you should not rely on the information contained in this tutorial remaining true. Further information may be found in this forum thread.

It appears the wiki is up to date, now. Should the wiki warning now be removed?

Thanks!
Amy

[Chris Davenport]

Wiki warning has been removed.

Thanks for the reminder Amy.

Chris.

[Kampp]

The wiki link does not work anymore....

[Chris Davenport]

It's been moved to the "new" wiki: http://docs.joomla.org/Using_caching_to ... _your_code

Regards,
Chris.