Placement of Code in Plugin for hooking `save_post`

Question

I ran into a strange Problem today developing a new Plugin.

I set it up as usual, creating the f711-roomprice folder in the Plugindirectory, and creating the f711-roomprice.php as well as an inc directory in there.

Everything worked fine with the activation hook and the included functions, until i created an include:

include('inc/filter-savepost.php');

this file contained the following code:

add_action( 'save_post', 'f711_roomprice_meta_box_save' );  
function f711_roomprice_meta_box_save( $post_id ) {

    if( !isset( $_POST['f711_roomprice_prices'] ) ) return;

    if( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) return; 

    if( !isset( $_POST['meta_box_nonce'] ) || !wp_verify_nonce( $_POST['meta_box_nonce'], 'f711_roomprice_box_nonce' ) ) return; 

    if( !current_user_can( 'edit_post', $post_id ) ) return;

    foreach( $_POST['f711_roomprice_prices'] as $room => $seasons ) {
        foreach( $seasons as $season => $price ) {

            f711_roomprice_insert( $room, $season, $price );

        }

    }

}  

After including the file in my main plugin file, I got an Error resulting in a white screen on Saving a post, everything else worked fine.

The function f711_roomprice_meta_box_save is called, confirmed this with an wp_die('f711_roomprice_meta_box_saveis called') in there.

Now the strangest thing is, i placed the code (exactly the same as in the include file) in my main Plugin file, and skipped the include of course. Now it works just as I want it to.

I also tried just adding the save_post action in the main Plugin file and including the function from inc/filter-savepost.php, still got the wrong result as before.

What am I doing wrong here? Is the placement of the Code (Hooks, Functions) really important in a Plugin, or is it just something on my part gone wrong?

Answer 1

I'm not sure if

if( !current_user_can( 'edit_post', $post_id ) ) return;

really works. Maybe the current user isn't set up there and you'll have to work around it by passing the user ID in a hidden field, then retrieving it using

$user = get_user_by( 'id', esc_attr( $_POST['user_id'] ) );
wp_set_current_user( $user->user_id );
if ( ! current_user_can( 'edit_post', $post_id )
    wp_die( 'Not allowed' );

Answer 2

Browsing through my old questions, I reopened this one and tested some things out in my plugin.

The solution was quite simple, although I am not sure if it had something to do with a new version of WordPress as well.

I refactored the plugin and noticed different encodings than last time I tested this. I don't know how I did not recognize this. Now, everything being UTF-8 without BOM, and nicely structured into different files (as it was planned), it works fine.