make user_id in a shortcode dynamic based on who's logged in

Question

I basically have a contact form which generates a PDF output using a third-party plugin. The plugin allows for the use of shortcodes to add content to the final PDF.

I want to be able to display the avatar image of the currently logged in user so the PDF is customized for them and not just a default look. The shortcode below works great and if I manually change the user_id it will changes the image perfectly to whom ever that ID belongs to.

However I can't seem to find for the shortcode to dynamically change the user_id number to represent who's actually logged in ... or at least i've not understood clearly the route I need to take from other support posts.

[user_profile_avatar size="original" user_id="1"]

Can someone kindly guide me how to do this and where I need to place code etc. Would be much appreciated. I have some coding knowledge but still learning. I've tired the plugin developers wordpress support page but they haven't answered anyone's request in months.

Answer 1

One option is to register your own shortcode to act as a wrapper for the plugin's shortcode. In the wrapper callback you would then retrieve the current user's ID and pass it to the actual shortcode.

Simplified example,

add_shortcode( 'my_user_profile_avatar', 'my_user_profile_avatar_callback' );
function my_user_profile_avatar_callback( $atts, $content = null ) {
  // (int) The current user's ID, or 0 if no user is logged in.
  return do_shortcode(
    '[user_profile_avatar size="original" user_id="' . get_current_user_id() . '"]'
  );
}

N.B. not tested, but should work.

This would then be used as [my_user_profile_avatar] wherever shortcodes are accepted.

If you can find out the name of the actual shortcode's callback, then using it directly instead of do_shortcode() inside your shortcode's callback would be more efficient. Something along these lines,

function my_user_profile_avatar_callback( $atts ) {
  // (int) The current user's ID, or 0 if no user is logged in.
  $atts['user_id'] = get_current_user_id();
  // dig into the plugin's source code to find the callback's name
  return original_shortcode_callback_function($atts); // might require more parameters
}

The custom shortcode registration can be done in your (child) theme's functions.php file or with a custom plugin.