Wegwarte

I haven’t disabled wp-cron by inserting “define(‘DISABLE_WP_CRON’, true);” into the wp-config.php file, but since my site doesn’t have many visits, and my server doesn’t provide cron jobs, I set up a cron job on a local Raspberry Pi to trigger wp-cron every minute:

* * * * * wget -O- https://mydomain.com/wp-cron.php > /dev/null

The garbage collection was deactivated (0 seconds). And in the garbage collection section of the settings, there was a warning that supercache files aren’t removed because preload is activated.

Meanwhile I’m using a bash script to rebuild the cache files for all posts automatically every hour (iterating through the post URLs from the sitemap.xml and calling wget on each URL).

Thanks; but I know the crontab syntax.

I have now come to an own preload solution: A bash script (rebuild-cache.bash) which parses the sitemap.xml and gets every post URL in a loop. This way the entire cache for all posts is rebuild within 4 minutes.

#!/bin/bash

> sitemap.xml
wget -O- "https://mydomain.com/sitemap.xml" > sitemap.xml 2> wget.err

if [ "$?" -ne 0 ]
then
	echo "Error getting sitemap.xml: $(<wget.err)"
	exit 1
fi

for urlSubmap in cat sitemap.xml | grep '<loc>' | awk -F'[\<\>]' '{print $3}'
do
	echo "Submap: $urlSubmap"

	wget -O- "$urlSubmap" > submap.xml 2> wget.err

	if [ "$?" -ne 0 ]
	then
		echo "Error getting $urlSubmap: $(<wget.err)"
		exit 1
	fi

	for urlPost in cat submap.xml | grep '<loc>' | awk -F'[\<\>]' '{print $3}'
	do
		echo "Post: $urlPost"

		wget -O- "$urlPost" > post.html 2> wget.err

		if [ "$?" -ne 0 ]
		then
			echo "Error getting $urlPost: $(<wget.err)"
		fi
	done

done

Another bash script (clear-cache.bash) clears the cache:

#!/bin/bash

> wget.out
wget -O- "https://mydomain.com/?action=wpfastestcache&type=clearcacheandminified&token=xyz123" > wget.out 2> wget.err

if [ "$?" -ne 0 ]
then
	echo "Error clearing cache: $(<wget.err)"
	exit 1
fi

RESULT=$(<wget.out)

if [ "$RESULT" != 'Done' ]
then
	echo "Error clearing cache: $RESULT"
	exit 1
fi

echo "Cache cleared sucessfully."

Both scripts are executed by cron:

0 0 * * * ~/clear-cache.bash > clear-cache.log
1 * * * * ~/rebuild-cache.bash > rebuild-cache.log

At 0:00 pm the cache is cleared, and every hour (0:01, 1:01, …) it is rebuilt.

Since I don’t have cron on the shared webserver whith the WordPress installation, the scripts are running on a Raspberry Pi (which I’m using as a “Pi-Hole”).

So far this solution is working for me. If there’s an easier solution using built-in features of WP Fastest Cache to achieve the same, then please tell me…