[Resolved] Post relationships API help

[Author]

Posts

[geophray]

Tell us what you are trying to do?
I'm trying to write a function for calculating the value of a field when the post is updated based on the value of a different field in all related posts of a different type. Here is what I have so far with notes on what I'm trying to accomplish in each line.

// When a Staff Member bio is created or updated, trigger the updateStaffReviewStats() function.
add_action('save_post_{$post->staff}', 'updateStaffReviewStats', 10, 1);
// Function for updating the aggregate review rating and review count for a staff member
function updateStaffReviewStats($post_ID) {
    // Find out if there are any reviews related to the Staff Member
    $myReviews = toolset_get_related_posts(
        $post_ID,
        'staff-member-review',
        [
            'query_by_role'     => 'parent',
            'role_to_return'    => 'other',
            'args'              => [ 'post_status' => 'published' ]
        ]
    );
    // If there are no related reviews, exit function
    if(!$myReviews) { return; }
    // Otherwise set reviewSum and reviewCount to 0
    $reviewSum = 0;
    $reviewCount = 0;
    // Loop through related reviews
    foreach($myReviews as $review) {
        // Calculate the average rating value 
        $reviewSum = $reviewSum + $review['wpcf-review-rating'];
        // Count total number of reviews 
        $reviewCount++;
    }
    // Calculate the average and store it in $avgRating
    $avgRating = $reviewSum / $reviewCount;          
    // store avgRating in the wpcf-aggregate-staff-member-rating field for the current staff member
    // store the count in the wpcf-total-reviews-for-staff-member field for the current staff member
    // Update post 37
    $staff_post = array(
        'ID'           => $post_ID, 
        'wpcf-aggregate-staff-member-rating'   => $avgRating,
        'wpcf-total-reviews-for-staff-member' => $reviewCount
    );

    // Update the post into the database
    wp_update_post( $staff_post );
}

When I update a test post of type "staff" that has multiple reviews associated with it, nothing seems to happen, and I'm not 100% sure where to go from here with regard to troubleshooting.

Is there any documentation that you are following?
https://toolset.com/documentation/customizing-sites-using-php/post-relationships-api/#toolset_get_related_posts

Any guidance you can give with regard to using the toolset api would be greatly appreciated. I know this is beyond the scope of your normal support, so if you can't help me I completely understand. Even a nudge in the right direction would be appreciated.

Thanks a million. 🙂

[Nigel]

Hi there

A couple of observations:

You can't use save_post_{$post->staff} for your action, you need to use the generic save_post action with a priority of at least 30 (https://toolset.com/documentation/customizing-sites-using-php/updating-types-fields-using-php/).

You seem to be treating custom fields (stored in wp_postmeta) as if they were standard fields that are part of the post object (those stored in wp_posts).

toolset_get_related_posts will return an array of post IDs by default (although you can specify it should return an array of post objects), see https://toolset.com/documentation/customizing-sites-using-php/post-relationships-api/#toolset_get_related_posts. But even an array of post objects has standard fields, not custom fields, and you need to use get_post_meta to retrieve the custom field values (https://developer.wordpress.org/reference/functions/get_post_meta/).

Likewise, wp_update_post will set your standard field values, but to update custom field values you would use update_post_meta (https://developer.wordpress.org/reference/functions/update_post_meta/).

[geophray]

Thank you Nigel... this is all VERY helpful. I appreciate the gentle nudge in the right direction. I haven't been able to jump back into this quite yet but I wanted to thank you for your time before my ticket was auto-closed. 🙂