0

I want to write a simple Wordpress plugin. The plugin will:

  1. Read (if set) a cookie from the visitor
  2. Send a cookie (if not set) to the visitor
  3. Depending on the cookie value I will redirect the user to a new pages

I found some documentation for getting/setting cookies through WP, and I'm guessing I can just issue a redirect from PHP. So I downloaded the WordPress Boilerplate (WPBP) code and so far so good. But I'm stuck at:

  1. Which WP callback should I hook into for my code? (init ?) I found the plugin documentation but I'm struggling to understand where this type of code should hook into.
  2. Should I put any of my code into the main/global portion of the WPBP file? Or only in the called back function.
  3. This plugin will run on a WP multisite installation. Does that mean my plugin code would run on every site? If so, how could I restrict my plugin code to run on only a particular site? (PHP check for a URI?)

1 Answer 1

1

Your questions about how you should structure your plugin are somewhat too broad, but here is a specific answer to the title question.

To change headers before they’re sent, use the wp_headers filter.

function tsg_filter_headers( $headers ) 
{
    // For debug. This will break your page but you will see which headers are sent
    // print_r( $headers );

    // It’s a good idea to leave the admin alone
    if ( !is_admin() ) {

        // Add or redefine 'Content-Location' header
        $headers['Content-Location'] = '/my-receipts/42';
    }

    return $headers;     
}
add_filter( 'wp_headers', 'tsg_filter_headers' );

See the WordPress doc here.

1
  • 1
    Great thanks - and I'll split my question above
    – TSG
    Sep 25, 2019 at 22:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.