I have a meta field called `postexpiry`, and I want to set the value to the publish date, + 2 weeks.
So if today were October 3rd, I want the field to be set to October 17th.

I was thinking about creating a hook to the `publish_post` filter, but I am not sure how to add 2 weeks on to `get_the_date()`. 

I know with php I can do something like this `$dateInTwoWeeks = strtotime('+2 weeks');` but I'm not sure how to use that with `get_the_date()`

Thanks!

**UPDATE**

I tried the following code, but it didn't do anything:

```
function dp_expiry() {

$dp_new_expiry_date = strtotime( '+2 weeks', strtotime( $post->post_date ) );
update_post_meta( get_the_ID(), 'postexpiry', $dp_new_expiry_date );
}

add_action( 'publish_post', 'dp_expiry' );

```

**Also**, my theme requires that the date be in `yyyy-mm-dd` format.

**UPDATE 2**

This code outputs "1209600" to the field. Any ideas? Thanks!

```
add_action('publish_post', 'dp_expiry');
function dp_expiry( $data ) {

$dp_new_expiry_date = strtotime( '+2 weeks', strtotime( $post->post_date ) );

update_post_meta( $data['post_id'], 'postexpiry', $dp_new_expiry_date );
}

```