I want to run a function after the `wp();` line in the file `wp-blog-header.php`, what is the proper `hook` to use here?

```php
<?php
/**
 * Loads the WordPress environment and template.
 *
 * @package WordPress
 */

if ( !isset($wp_did_header) ) {

    $wp_did_header = true;

    // Load the WordPress library.
    require_once( dirname(__FILE__) . '/wp-load.php' );

    // Set up the WordPress query.
    wp();

    /********************************************
       I WANT TO RUN THE FUNCTION AT THIS POINT 
     ********************************************/

    // Load the theme template.
    require_once( ABSPATH . WPINC . '/template-loader.php' );

}

```

### Why do I need the hook

We are migrating to a new website and we have to care about the old URLs, so what I did:

1. Added the following `rewrite` rule to our `NGINX` config file:

`rewrite \D+(\/\d+\/\D+)$ /index.php?redirect=$1 break;`

This rule will add an extra parameter `redirect` to the URL (old URL) with a value that I will be using to get the new final URL.

2. Then I will run the following code to get this value from the incoming URL and get the final URL by querying a 2-columns table that maps each value `redirect_from` with a final URL `redirect_to`:

```php
/**
 * 1. Check if the URL has a parameter [redirect]
 * 2. If NO, proceed to the next step
 * 3. If YES, then get that parameter value and look into [redirects] table
 * 4. If you found a row that has that value, then get the [redirect_to] value
 * 5. Redirect to that URL [redirect_to]
 */

if (isset($_GET['redirect'])) {
    // Get the parameter value from the URL
    $redirect_from = $_GET['redirect'];
    // Add the table prefix to the table name
    $table_name = $wpdb->prefix . 'redirects';
    // The SQL query
    $query = "
        SELECT redirect_to
        FROM $table_name
        WHERE redirect_from = '$redirect_from';
    ";
    // Run the SQL query and get the results
    $result = $wpdb->get_results($query, OBJECT);

    // If there was a result then do the redirection and exit
    if (wp_redirect($result[0]->redirect_to)) {exit;}
}

```

**Note:**
No way to get the new URLs from old URLs, here is an example of the old and new URLs:

Redirect from:

`http://www.example.com/category/sub-category/post-id/slug`

to:

`https://www.example.com/category/sub-category/yyyy/mm/dd/slug`