Setup wordpress cron jobs and debug methods

Setup wordpress cron jobs and debug methods

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Why would you need to setup WordPress cron jobs ?

Cron jobs in WordPress can be set for following reasons

  1. You have a custom post type for events and you wish to archive all your old events at regular intervals
  2. Archive logs e.g. if you have some plugin which tracks user activity then you may want to archive the logs table at regular intervals
  3. If you have integrated wordpress with some external application e.g. a mailing server then you need to synchronise your mailing lists with the external server
  4. Clearing caches for certain pages

How to setup wordpress cron jobs

wp_schedule_event is the function used to set up wordpress cron jobs

Here’s a sample code to set up a cron job

The above code will execute the function wpi_some_cron_job on daily basis. Some of the other options are hourly, twicedaily

Now the question is where do we add the above code. The answer to this depends whether you want to set this up as part of your own custom plugin or this cron is just some adhoc function which you wish to execute for housekeeping purpose e.g. clearing expired transients in your wp_options table.

Here is the code to add the cron job in the activation hook of your own plugin

Here is the code to add the cron job within your functions.php

If you have added the code to the activation hook of your plugin, it needs to be deactivate once the plugin is deactivated. Here’s how you deactivate.

Debugging WordPress Cron jobs

A. Try triggering the WordPress cron engine manually by opening below URL in your browser

http://example.com/wp-cron.php?doing_wp_cron

B. Turn on WP_DEBUG on your development environment by adding below line in your wp-config.php file

C. Create some custom field for debugging purpose and set the custom field to increment every time through a cron job runs. Then check if the field gets updated.

Automatic Database backups using free Sypex Dumper tool

Photo credit – williamhook2631871046

Automatic database backups can be set up very easily using a simple shell script and a cron job. However it may not be a practical solution for huge databases and the restoration process can also be difficult. There are various tools available to make this process simple. Sypex Dumper is just one of them.

What is Sypex Dumper

Sypex Dumper is a software product (PHP-script), which can help you create a backup copy (dump, export) of a MySQL database, and also restore the database from the backup file if needed. Read more and download

With this tool huge databases can be backed up and restored with very high speed using least server resources and greatly reducing the size of the database dumps.

Free version of the tool is enough to create the automatic backups. The Paid version allows to selectively restore a particular table from the entire database.

Steps to set up automatic Database Backups

Let’s assume you want to create backup of your database every day and keep the recent 30 backups on your server

Create the required job in SXD

1. Login to Sypex Dumper with your database user credentials

Setup automatic database backups using Sypex Dumper

2. Click on the Export option

3. Select the database from the Database drop down

4. Since we want to keep only the last 30 database backups add 30 in the Autodelete If number of files more than box.

5. Add some comments e.g. Last 30 backups

6. Clicking the Save button will create the backup job with the name specified

Create the shell script to execute the job

Now that the job is created we want to execute it using a shell script. Here is a sample script

Automate the script

Finally just add the above script to a cron job so that it runs once daily