Why does my file_exist check fail?

Question

So basically, I'm trying to check if the user wants to overwrite my plugin template in his theme.

I have a plugin with a Custom Post Type 'links'. According to WP template system my archive file is 'archive-links.php'.

So, why does my check for the file 'archive-links.php' in the template folder always return false?

if(is_post_type_archive('links')) {

    $file = get_template_directory_uri() . '/archive-links.php';

    if(file_exists($file)) {
        // echo('working');
        // template overwrite
        return get_template_directory_uri() . '/archive-links.php';
    } else {
        // echo('not working');
        // default plugin archive file
        return plugin_dir_path(__DIR__) . 'templates/archive-links.php';
    }
}

Answer 1

get_template_directory_uri doesn't return the directory name, it returns the URL of the directory. file_exists needs a file path, not a file URL.

Use get_template_directory instead, and don't forget to check get_stylesheet_directory too for those using child themes