I am using the function in this answer to upload, attach and then [set_the_post_tumbnail][2]/featured image to a post which I am creating from an RSS feed.
I ran a test and the output is showing that the attachment ID matches my thumbnail ID. I checked in the media library and it is assigning the correct IDs according to get_post_thumbnail_id but the problem is my featured image meta box is not displaying the image through the dashboard or when using [get the post thumbnail][4] in my template.
Am I missing any steps here? The code is mostly from the answer linked above with a few tests on the end.
global $wp_query;
wp_insert_post($my_post); // create a new post
$post_id = $wp_query->post->ID; // get the ID for the new post
$image_url = $thumbnail;
$upload_dir = wp_upload_dir();
$image_data = file_get_contents($image_url);
$filename = basename($image_url);
if(wp_mkdir_p($upload_dir['path']))
$file = $upload_dir['path'] . '/' . $filename;
else
$file = $upload_dir['basedir'] . '/' . $filename;
file_put_contents($file, $image_data);
$wp_filetype = wp_check_filetype($filename, null );
$attachment = array(
'post_mime_type' => $wp_filetype['type'],
'post_title' => sanitize_file_name($filename),
'post_content' => '',
'post_status' => 'inherit'
);
$attach_id = wp_insert_attachment( $attachment, $file, $post_id );
require_once(ABSPATH . 'wp-admin/includes/image.php');
$attach_data = wp_generate_attachment_metadata( $attach_id, $file );
wp_update_attachment_metadata( $attach_id, $attach_data );
set_post_thumbnail( $post_id, $attach_id );
echo "Attachment ID: " . $attach_id;
$post_thumbnail_id = get_post_thumbnail_id( $post_id );
echo "Thumbnail ID: " . $post_thumbnail_id;
get_the_post_thumbnail($post_id, 'full');
