Can a plugin redirect product page based on IF condition?

Question

I am new at WordPress and just made my first plugin to add some custom fields to WooCommerce. Depending on these custom fields, I want to redirect my product page.

The active theme has a template override for single-product.php. I added some conditional logic there and used wp_redirect() to make it work. And that works just fine.

But when the theme will be updated, this conditional logic will be lost. Is it possible to override a template file using a plugin, but only if conditions are met?

Something like:

$redirectPage = true;
if ($redirectPage) { // don't use template, redirect to some page (this part works)
   $targetUrl = ...;
   wp_redirect($targetUrl, 301);
   exit();
} else {
   // now we want to keep normal behavior
   // use excisting single-product.php file from theme
   // how to do it?
}

Any insights if this is possible? Can someone point me in the right way? I understand I can make use of a subtheme but I would prefer to handle everything inside a plugin. Thanks.

Answer 1

Okay.. After some more reading I came to a working solution.

First we make the plugin listen IF the type of page is a product page. Then IF that is true, conditional logic can be implemented. This way it's update proof and it also works on any other template. Great!

Here 's the code I added in plugin (somewhat minified to the basics):

add_action( 'wp', 'redirect_single_product_page' );

function redirect_single_product_page() {
    if (is_product()) { // if the page is a single product page
        $redirectPage = true; // some dummy value for conditional logic
        if ($redirectPage) {
            $target_url = ...; // construct a target url
            wp_redirect($target_url, 301); // permanent redirect
            exit();
        }
    }
}

If the page does not meet the conditional logic, normally expected behavior applies.