Expression Engine WXR Export Class

Earlier, I shared with you a new base class I’m releasing into the wild. While that was a conceptually nice piece of code, and potentially useful, it didn’t really translate in usefulness without some actual code.

As mentioned, I just moved Shai to WordPress from Expression Engine and it required writing a custom export routine. Instead, I wrote the base class in conjunction with this extension class.

This could very well be a very good example for someone wanting to write their own routine. While it is custom to Expression Engine and would look different for other platforms, the bottom line is that the methods in the base class have to be fed certain data.

As with the base class, this is meant for advanced WordPress hackery and is not a plugin nor for rookies. I don’t mean to sound condescending, but it took me years to wrap my head around object oriented PHP and so please don’t ask me. :-)

I can say that if you dive into this code, you will find the roadmap to your own importer. This is fully functional. It works. It’s for Expression Engine, but it works. Your methods should return similar data.

One day I’ll get around to documenting it, but my mind is mush after working on this all weekend. :-)

Update: Oops, forgot where you can download. Subversion it is again:

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svn co http://svn.aaronbrazell.com/wpwxr/tags/expression-engine/ expression-engine

WordPress WXR Class

One of the most frustrating things to me in my years of working with WordPress and b5media has been migrating blogs into WordPress. Every blog platform does things differently and although WordPress has import support for a large number of blog platforms, it always seems like I get the job of migrating from platforms that don’t have any way of exporting posts to take to a different platform, such as WordPress.

I’ve done a number of these migrations now – Nucleus, Drupal, Serendipity and others. The latest was Expression Engine – needed to move Shai’s blog over to WordPress. This was the catalyst I needed to write a base class for the WordPress import/export format known as WXR, or WordPress eXtended RSS.

For casual users, this is not for you. For developers, this may be a life saver for you.

The class can be downloaded via SVN:

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svn co http://svn.aaronbrazell.com/wpwxr/trunk wpwxr

Included in this repository is the base

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class.wxr.php

class along with sample code to build your own apps from.

Reference: Complete WordPress WXR Base Class documentation is online.

Instantiation: This is a base class. Therefore, you should never extantiate it directly – only via another class via extending.


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class myNewClass extends WXR_export {

    function myfunction()
    {
        echo "Hello World!";
    }
}

Debug mode: If you wish to use debug mode, you can set the

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$debug

property of the class to true. The default is false. If debug mode is on, output will be sent to the screen as opposed the the WXR file.

Example:


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$n = new myNewClass;
$n->debug = true;

Export Filename: By default, the name of the WXR file is date based (e.g wxr-2008-01-26.xml). You can change this by changing the

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$export_filename

property.


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$w = new myNewClass();
$w->export_filename = 'file-movabletype.xml';

I’d love to get patches if you want to contribute. You should send them to emmensetech [at] gmail [dot] com. In addition, if you use this and create extension classes, I’m more than happy to host them. I’ll be seeding the pot with the Expression Engine class I used this weekend.

Exporters Built