Prevent Akismet plugin from auto-deleting comments

If you’re using the Akismet plugin on your WordPress site, you love its ability to identify spam comments and automatically block them from appearing on your blog… that’s something we all should appreciate greatly.

The little issue here is that Akismet will always automatically delete any flagged comment that’s older than 15 days. There is no option to disable or change this interval.

What’s the problem with that?

• Nothing is perfect and false positives are a possibility; in fact, it’s already happened. This means that a legitimate comment is flagged as spam.
• Maybe you’re being stalked or harassed and you need to keep these comments as a research aid or as evidence.

If you neglect to take action within 15 days, these flagged comments are permanently deleted by the plugin.

What’s the cause?

A function within the Akismet plugin called `akismet_delete_old` checks the age of flagged comments and just proceeds to delete anything older than 15 days.

function akismet_delete_old() {
	global $wpdb;
	$now_gmt = current_time('mysql', 1);
	$comment_ids = $wpdb->get_col("SELECT comment_id FROM $wpdb->comments WHERE DATE_SUB('$now_gmt', INTERVAL 15 DAY) > comment_date_gmt AND comment_approved = 'spam'");
	if ( empty( $comment_ids ) )
		return;
		
	$comma_comment_ids = implode( ', ', array_map('intval', $comment_ids) );

	do_action( 'delete_comment', $comment_ids );
	$wpdb->query("DELETE FROM $wpdb->comments WHERE comment_id IN ( $comma_comment_ids )");
	$wpdb->query("DELETE FROM $wpdb->commentmeta WHERE comment_id IN ( $comma_comment_ids )");
	clean_comment_cache( $comment_ids );
	$n = mt_rand(1, 5000);
	if ( apply_filters('akismet_optimize_table', ($n == 11)) ) // lucky number
		$wpdb->query("OPTIMIZE TABLE $wpdb->comments");
}

You could edit it yourself from 15 days to whatever. Or you could remove the call to this functionality entirely.

However, I don’t recommend editing plugins as every time a plugin is updated to a new version, you’ll lose your edits. That, among other reasons, makes it not a good practice.

What’s the real solution?

Use WordPress’s `remove_action()` function to remove the function in the Akismet plugin that deletes old comments.

Simply place this line in your theme’s `function.php` file…

`remove_action(‘akismet_scheduled_delete’, ‘akismet_delete_old’);`

However, any time you switch themes, you’ll also lose this custom function. Instead, you can easily break this dependance by saving the following code in a `php` file uploaded to your WordPress plugin directory. It will automatically show up in the plugins section of your WordPress Dashboard. I named mine `Akismet Keep Comment` and it’s saved in a file at `/wp-content/plugins/Akismet_keep_comment.php`. Yes, you just created a real WordPress plugin.

<?php
/*
Plugin Name: Akismet Keep Comment
Plugin URI: https://www.johnkieken.com
Description: This plugin removes any comment deletion ability of the Akismet plugin.
Author: John Kieken
Version: 1.0
Author URI: https://www.johnkieken.com
*/

remove_action('akismet_scheduled_delete', 'akismet_delete_old');

?>

What about this checkbox option in the Akismet plugin?

“Auto-delete spam submitted on posts more than a month old.”

It doesn’t mean what you might think. Upon first reading, I thought it simply meant “auto-delete blog spam that’s more than a month old”. So by leaving it un-checked, I erroneously thought no comments would ever be deleted.

Okay, so what does “Auto-delete spam submitted on posts more than a month old.” really mean?

It means that if your posting is more than a month old, spam comments will be deleted instantly (rather than being held for 15 days). This part is in parenthesis because you have to dig through the php code to determine that comments are being auto-deleted after 15 days- no matter what.

I’ve discussed this issue with the developer and the possibility of the Akismet plugin having user controlled options for comment deletion. Unfortunately, they are very adamant about not allowing the user to have any control whatsoever over this automatic comment deletion. I guess you better hope there’s never a false positive. They are concerned about your server filling up with comments. Really? Many blogs are plagued with much bigger problems like hundreds of posts and thousands of images. What bothers me the most is the total lack of disclosure or documentation explaining that flagged comments will be auto-deleted, and after only 15 days.

I firmly believe this is an issue best left to the site admin, his webmaster and hosting provider to manage. No plugin should be blindly deleting comments, even those flagged as spam, without some admin control or knowledge.