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How to use after_mu_upgrade action in WordPress

Sandeep Kumar Mishra
Sandeep Kumar Mishra
August 10, 2022
5 minutes read

after_mu_upgrade action

Fires after the Multisite DB upgrade for each site is complete.

To use the after_mu_upgrade action, first, you have to register it using add_action. You can write this code into the functions.php of your activated theme or in a custom WordPress Plugin.

We at WePlugins always prefer to create a custom WordPress Plugin while using hooks so nothing breaks when you update your WordPress Theme in the future.

In the below live example, we have defined a function weplugins_execute_on_after_mu_upgrade_event which takes 1 parameter and we registered using add_action. The first parameter after_mu_upgrade is the name of the hook, the second parameter weplugins_execute_on_after_mu_upgrade_event is the name of the function which needs to be called, the third parameter is the priority of calling the hook if the same hook is used multiple times, and the last parameter is the number of arguments (if any) to be passed in the registered function.

Sometimes, you have to remove a registered hook so you can use remove_action to remove the after_mu_upgrade action.

Parameters

    Below the 1 parameter is required to use this hook.

  • $response : (array) The upgrade response array.

Live Examples

Example 1: Basic Hook Usage

Below is an example of how you can use this hook.

    function weplugins_execute_on_after_mu_upgrade_event($response){
       //You can write code here to be executed when this action occurs in WordPress.
       // Use the parameters received in the function arguments & implement the required additional custom functionality according to your website requirements.
    }
    // add the action
    add_action( "after_mu_upgrade", "weplugins_execute_on_after_mu_upgrade_event" , 10, 1);
    

Example 2: Removing a Hook Callback

To remove a hook callback, use the example below.

    remove_action( "after_mu_upgrade", "weplugins_execute_on_after_mu_upgrade_event", 10, 1 );
    

Please make sure to provide the same callback function name, priority, and number of arguments while removing the hook callback.

Example 3: Logging Upgrade Response

This example demonstrates logging the upgrade response to a custom log file for debugging purposes.

    function weplugins_log_mu_upgrade_response($response){
        $log_file = ABSPATH . 'wp-content/mu-upgrade-log.txt';
        $log_data = json_encode($response) . PHP_EOL;
        file_put_contents($log_file, $log_data, FILE_APPEND);
    }
    // add the action
    add_action( "after_mu_upgrade", "weplugins_log_mu_upgrade_response" , 10, 1);
    

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Contact Us

If you’re having any trouble using this hook or need customization, please contact us and we’d be happy to assist you.

Sandeep Kumar Mishra

Sandeep Kumar Mishra

Sandeep Kumar Mishra writes about WordPress and Artificial Intelligence, offering tips and guides to help you master your website and stay updated with the latest tech trends.

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