How to update a taxonomy term for a custom post type with auto incrementing number

Question

I am trying to do something similar to this block of code - but with tax terms within a taxonomy rather than custom fields in a post

In short, I want to auto increment a simple number value in a taxonomy term for a custom taxonomy when the term is saved so that, each time a new term is created in the cms, it is auto assigned the next number higher from the previous term - so I would end with a list of tax terms like this

taxonomy: job number terms: 1, 2, 3, 4, 5, 6 and so on

Thanks

/**
* Add an auto-incrementing Project ID field to Design feedback posts
*/
function auto_assign_ids( $post_id, $post, $update ) {

// Only assign ID to new design posts
if ( $post->post_status == 'publish' && $post->post_type == 'designapprovalsystem' ) {

    // get the most recent Project post
    $project_args = array(
        'numberposts'       =>   2,
        'post_type'         =>   'designapprovalsystem',
        'orderby'           =>   'post_date',
        'order'             =>   'DESC'
    );
    $projects = get_posts( $project_args );

    // get the project_id of the prior post
    //get the custom field value of a post
    $last_id = get_post_meta( $projects[1]->ID, 'job_number', true );

    // increment
    $last_id++;

    // set the project_id of the current post
    update_post_meta( $post_id, 'job_number', $last_id );
    }
 }
add_action( 'save_post', 'auto_assign_ids', 100, 3 );

Answer 1

/**
* Add an auto-incrementing Project ID field to Design feedback posts
*/
function auto_assign_ids( $post_id, $post, $update ) {

// Only assign ID to new design posts
if ( $post->post_status == 'publish' && $post->post_type == 'designapprovalsystem' ) {

    // get the most recent Project post
    $project_args = array(
        'numberposts'       =>   2,
        'post_type'         =>   'designapprovalsystem',
        'orderby'           =>   'post_date',
        'order'             =>   'DESC'
    );
    $projects = get_posts( $project_args );

    // get the project_id of the prior post
    //get the custom field value of a post
    $last_id = get_post_meta( $projects[1]->ID, 'job_number', true );

    // increment
    $last_id++;

     // set the project_id of the current post
     if ( !add_post_meta( $post_id, 'job_number', $last_id, true ) ) { 

     update_post_meta( $post_id, 'job_number', $last_id );

     }

    }
 }
add_action( 'save_post', 'auto_assign_ids', 100, 3 );

I'm not 100% sure but I think the issue is that the page doesn't have an ID yet so you can't update it, you have to insert it first.