mu-plugins – Behind the Scenes

When we first started Jerry’s original three legged dog blog to share the news about his osteosarcoma treatment and recovery, we never in our wildest dreams expected tripawds.com to grow into such an incredible community of support for so many people facing a bone cancer diagnosis or amputation for their dogs.

While installing Simple:Press to power the Tripawds Discussion Forums was the first of many content enhancing improvements, it was our migration from WordPress to WPMU and subsequent transition to our current WordPress Multisite network that make the site such the valuable resource it has become.

In fact, Tripawds was recently added to the acclaimed WPMU Dev Showcase among some of the leading WordPress MultiSite communities online!

Best WordPress Multisite Plugins & Themes

So what exactly makes this network work? Simply said, it’s our WPMU Dev Premium subscription that enables us to offer such amazing functionality. Here’s a rundown of some of our favorite WPMU Dev plugins and themes that power the Tripawds community.

Admin Ads: We provide a row of dashboard “Quick Links” to many of our community’s most valuable resources using this simple plugin. It also allows us to notify bloggers of pending upgrades and other special announcements.

Admin Help Content: This provides a simple interface for creating the custom content we provide in users’ dashboard Help drop-down menu, instead of confusing them with the default WordPress support forum links.

Anti-Splog: This ultimate spam blog plugin and service stops nearly all splogs from even being created in our WordPress Multisite network. If a splog does get created, no posts are visible to the community, and an easy interface allows us to moderate or delete them.

Avatars: Ths is how we allows users to upload ‘user avatars’ and ‘blog avatars’ which then appear in blog / forum comments and blog / user listings throughout the Tripawds community.

Blogs Directory: This plugin provides a paginated, fully searchable, automatic and rather good looking directory of all of the blogs on our WordPress Multisite installation.

Members Directory: This creates and automatic directory of all Tripawds users, with avatars, pagination, and a built in search facility with extended customizable user profiles.

Invite: Allows all Tripawds bloggers to invite their friends and colleagues via email to check out their blog and register for a Tripawds account.

Recent Comments: This widget lets us display a list of recent comments from all Tripawds blogs throughout the News blog.

Recent Global Posts Widget: This widget shows recent posts from all Tripawds blogs, with user avatars.

Sitemaps and SEO: Automatically generates and submit Google sitemaps for all blogs on this network

Supporter: Lets us easily offer paid Tripawds Supporter Blog accounts with automatic upgrades including premium themes, premium plugins, extra storage space, the ability to instantly remove banner ads and more.

Terms Of Service: This plugin places the Tripawds Terms of Service on the signup with an approval checkbox users must select in order to continue their registration.

The WordPress Popup Plugin: Allows us to display a simple ad directing new visitors to the valuable information in our first Tripawds e-book, Three Legs and a Spare – a Canine Amputation Handbook.

Update Notifications: This keeps us automatically updated of any WPMU Dev plugin and theme updates for best security and functionality!

WPMU Nelo: The custom homepage CMS WordPress theme we customized to improve navigation and address site performance issues.

What’s next?

I often turn to the WPMU Dev support forums for quick answers whenever I need help tweaking things behind the scenes here. I have requested development of a couple things that might help us continue enhancing the Tripawds experience. For instance, I’d like to have a Map plugin that would automatically generate a map page with member locations based on profile data.

With all this that we already offer in mind, what other new features might Tripawds members like to see?

I did it! WordPress Post Revisions

OK, with that said, I finally found this great SQL query for deleting old WordPress draft revisions.

What this means to Tripawds Bloggers

You may have noticed the Save Draft button in your Tripawds Blog post editor. This will do just that – save a current working draft of your post. Actually doing so, however, is unnecessary considering WordPress has it’s own auto-save function built right in. But if you are writing an important post and concerned about losing your work, go ahead and save your drafts. I am no longer concerned about database bloat!

Scroll down beneath your post editor after saving a draft and you will notice a section called Post Revisions. Clicking the link there will allow you to review the latest draft you saved, compare it to the most recent auto-save, and restore whichever one you prefer.

Why only one revision, and How?

Anyone familiar with WordPress may wonder why only one revision shows, no matter how many times the post is saved. Those very familiar might be asking how we did that.

Every saved post revision is stored in the WordPress database. Over time, especially in a WordPress MU environment, and particularly with users who tend to frequently save drafts, this can create excessive unnecessary database entries – said bloat I eluded to earlier. By limiting revisions to one draft, we are still allowing members to save important drafts and compare that draft with the current auto-save, while keeping unnecessary entries out of the database. FYI: Every draft manually saved will replace the most recent revision.

How did we do it? We are running the Limit Post Revisions WordPress MU plugin from the wpmudev.org project repository. I know, I know, limiting post revisions will not delete old drafts from the database, and that’s what truly enquiring minds want to know. We’re getting to that.

What use this is for WPMU Site Administrators

Limiting post revisions can also be done with this simple hack to your wp-config file, immediately following the db_collate definition, as in…

/** The Database Collate type. Don't change this if in doubt. */ define('DB_COLLATE', '');

/** Number of saved revisions; false acts as 0 */ define('WP_POST_REVISIONS', 1);

But I like to avoid editing core files whenever possible, and much prefer to use awesome WPMU plugins. But I digress, back to the task at hand – how to delete all those old revisions in the MySQL database driving your WordPress installation…

Here is the query I used, edited for use with WordPress MU:

DELETE a,b,c FROM wp_{id}_posts a LEFT JOIN wp_{id}_term_relationships b ON (a.ID = b.object_id) LEFT JOIN wp_{id}_postmeta c ON (a.ID = c.post_id) WHERE a.post_type = 'revision'

Simply replace {id} with the id for the blog on which you want to delete old post revisions. Backup your database first! To be safe, I also exported copies of the affected tables so I could restore them quickly if anything broke. But nothing did, at least not that I can tell, yet. 😉

In our case, I reduced file size of our wp_1_posts export from more than 11 MB to less than 2MB! Please note, this worked for me. No promises, and good luck!

Many thanks to Andrei for providing this query, and explaining how it will remove related entries from the postmeta and term_relationship (i.e.: tags, categories, etc.) tables. I found many references to the following query for deleting post revisions, but Andrei’s solution gave me the confidence that all unnecessary data would be deleted from the database.

DELETE FROM wp_posts WHERE post_type = "revision";

While we’re at it, for anyone looking to delete all old post revisions from a basic WordPress install, here ya go…

DELETE a,b,c FROM wp_posts a LEFT JOIN wp_term_relationships b ON (a.ID = b.object_id) LEFT JOIN wp_postmeta c ON (a.ID = c.post_id) WHERE a.post_type = 'revision'

Hope this helps someone, as much as it helped me!

Tag: mu-plugins

What makes Tripawds run?

Best WordPress Multisite Plugins & Themes

What’s next?

Trimming the Fat

What this means to Tripawds Bloggers

Why only one revision, and How?

What use this is for WPMU Site Administrators