Dynamically populate custom field with attachment id created by post image field

Hello,

First things first - Gravity Forms is amazing. Taking a look at the code under the hood... Me Gusta!

And on to my issue...

I am trying to populate a custom field's value with the attachment id generated by a separate post image field. I'm figuring I'll need to do something with functions fired on the gform_post_submission or gform_post_data hooks, but I'm really not sure how to get at the attachment ids properly.

Here is what I have now. It sort of gets the job done, but it's also pretty fragile due to the way that I'm determining the attachment IDs.

<?php
add_action( "gform_post_submission", "post_submission_handler" );
function post_submission_handler( $entry ){

  // Hacky way of determining attachment id
  #update_post_meta( $entry['post_id'], 'my_meta_key', $entry['post_id'] + 1); 

  // Less hacky, but still hacky way of determining the attachment id.
  $meta_key = 'my_meta_key';
  $attachment_index = 0; // 0 indexed. For example, GF post image field 1 will be the first attachment.
  $args = array(
    'order'          => 'ASC',
    'post_type'      => 'attachment',
    'post_parent'    => $entry['post_id'],
    'post_mime_type' => 'image',
    'post_status'    => null,
    'numberposts'    => -1,
  );
  $attachments = get_posts( $args );

  if ( $attachments ) {
    $counter = 0;
    foreach ( $attachments as $attachment ) {
      if ( $counter == $attachment_index ) {
        update_post_meta( $entry['post_id'], $meta_key, $attachment->ID );
        break;
      }
    }
  }

  return $entry;
}

I also toyed around with this idea, but it won't work because the GF image url is not the same as a post guid (not that this is a good approach to begin with, but at this point, I'm trying to just make it work.)

<?php
add_filter("gform_post_data", "gfcustom_set_pattern_post_type", 10, 2);
function gfcustom_set_pattern_post_type($post_data, $form){

  global $wpdb;
  $image_url = $post_data['images'][0]['url']; // this is not a guid though... (not to mention the 0 index approach being weak)

  // ...so this will not work:
  $thepost = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE guid = '$image_url'" ) );
  $post_data['post_custom_fields']['my_custom_field'] = $thepost->ID;

  return $post_data;
}

-goto10 (via wilson)

Hi Wilrevehl,

Since the post these images are attached to has just been created, there will be no other attachments to this post besides the image being uploaded in conjunction with the form submission. Because of this, it would be safe to use the method where you retrieve all attachments of the post that was just created. Since there will only be one attachment it is also safe to use the '0' index to retrieve the properties of that attachment. Here is the code I used to complete this:

http://pastie.org/1541593

Agreed! This would be a really nice feature. In the mean time can the code David Smith posted be used to retrieve the attachment URL of the first 'post image' field regardless of how many 'post image' fields are used in the same form?

All i wish to do is set the featured image of a post with the first image uploaded on a form via the 'post image' field.

Thanks for any help.