Migrating from MT 4 to WP 2.5+

On Sunday, I spent a good deal of time migrating a blog from Movable Type 4.X to WordPress 2.5+ and found myself pulling my hair out to allow for a safe migration.  

One of the issues that you always discover in any migration is that Wordpress and Movable Type do not maintain the same permalinks.  As a owner of a blog, you want to keep your old URLs (permalinks) consistent, since google (and other search engines) and links to your site are all based on the permalinks URLs.

After a number of hours, I figured out some of the ways of retaining the original permalinks from MT and allowing for it to be consistent in Wordpress.

Step 1: Modify WordPress Import mt.php file

In the /wp-admin/import directory, you will see a file called mt.php.  Open it up in your favorite editor and go to around line 330.  There you will see:

} else if ( 0 === strpos($line, "TITLE:") ) {

$title = trim( substr($line, strlen("TITLE:")) );

if ( '' == $context )

$post->post_title = $title;

else if ( 'ping' == $context )

$ping->title = $title;

 

Here, you will copy this collection of code and then paste the same content below this collection (essentially offering a duplicate of the TITLE option).  Then, you need to change:

• TITLE to be BASENAME
• $post->post_title to be $post->post_name
• $title to be $>postname
  

It turns out the MovableType gives you the name of the Permalink in the BASENAME variable and you can change the WordPress post name (or post-slug) in this manner.  You then get:

} else if ( 0 === strpos($line, "TITLE:") ) {

$title = trim( substr($line, strlen("TITLE:")) );

if ( '' == $context )

$post->post_title = $title;

else if ( 'ping' == $context )

$ping->title = $title;

} else if ( 0 === strpos($line, "BASENAME:") ) {

$postname = trim( substr($line, strlen("BASENAME:")) );

if ( '' == $context )

$post->post_name = $postname;

else if ( 'ping' == $context )

$ping->post_name = $postname;

After you make this change, save the file.

Step 2: Export your MovableType blog

In MT, you can export your data in the MT format by going to the following URL:

http://[YOUR WEBSITE DOMAIN HERE]/mt.cgi?__mode=start_export&blog_id=1

Save the file as a text file (blogname.txt).

Step 3: Import to your WordPress 2.5+ 

Once you save the file as a text file (blogname.txt), you then go to the Import functionality of your WordPress installation.  This is found at:

http://[YOUR TEMP DOMAIN HERE]/wp-admin/import.php

Once you go through the process of Importing the blogname.txt file, you will have the new site updated with the correct URLs/permalinks.  All of the slugs are also updated.

Hope this gets included in the next WP installation.