How to use pre_http_request filter in WordPress

Hey there! If you’re diving into the world of WordPress development, you’ve probably come across the term *hook*. They are like the magic wand for developers, allowing you to modify or add functionality to your WordPress site without changing the core files. One such hook is the *pre_http_request filter*. Curious about it? Let’s explore!

So, what does this filter do? Simply put, returning a non-false value from the filter will short-circuit the HTTP request and return early with that value. To use the *pre_http_request filter*, you need to register it using `add_filter`. You can write this code into the `functions.php` of your activated theme or in a custom WordPress plugin. At WePlugins, we always recommend creating a custom WordPress plugin for this purpose. This way, nothing breaks when you update your WordPress theme in the future.

Below are the three parameters required to use this hook:
– $preempt: (false|array|WP_Error) A preemptive return value of an HTTP request. Default false.
– $parsed_args: (array) HTTP request arguments.
– $url: (string) The request URL.

Now, let’s dive into some examples to see how this hook works in action!

Example 1: Blocking Specific Domains

In this example, we will block requests to a specific domain using the *pre_http_request filter*.

add_filter( 'pre_http_request', 'weplugins_pass_or_reject_request', 10, 3 );
function weplugins_pass_or_reject_request( $preempt, $parsed_args, $url ){
    if( strpos($url, 'http(s)://any_domain.com') !== false ){
        return new WP_Error( 'http_request_block', __( "This request is not allowed", "textdomain" ) );
    }
    return $preempt;
}

Example 2: Modifying Pre-HTTP Request Defaults

Here’s how you can use this hook to modify HTTP request defaults based on your website’s requirements.

function weplugins_modify_pre_http_request_defaults($preempt, $parsed_args, $url) { 
    return $preempt; 
}
// add the filter
add_filter( "pre_http_request", "weplugins_modify_pre_http_request_defaults", 10, 3 );

Example 3: Removing a Hook Callback

Want to remove a previously registered hook? Use the example below.

remove_filter( "pre_http_request", "weplugins_modify_pre_http_request_defaults", 10, 3 );

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

Contact Us

If you’re having any trouble using this hook or need some customization, don’t hesitate to reach out! Our team is here to help. [Contact Us](https://weplugins.com/contact) for more information.