Unserialize deep when returning arrays of metadata

[nacin]

Currently when retrieving an array of metadata values for an object (no meta key specialized), they are retrieved as serialized. Only when meta key is specified do we unserialize.

We should array_map( 'maybe_unserialize' ) on what we plan to return instead of forcing plugins to call that themselves.

[westi]

Sounds reasonable.
What is the WP function your going to patch here?

[nacin]

Patches get_metadata()

[nacin]

According to dd32 this patch doesn't go deep enough, and needs to go one level down. Sounds about right.

[mattkeys]

Recursive unserialize meta

[mattkeys]

@boonebgorges I heard your talk at SF WordCamp last weekend, very inspiring. I'd like to wet my feet with contributing to core and I have submitted a possible solution to this ticket.

Can you take a look and let me know if I am moving in the right direction here?

[mattkeys]

Updated version using an anonymous function

[mattkeys]

Looking this over again, I think using an anonymous function here might be more appropriate to avoid needing the new callback function in /wp-includes/functions.php, since that function is not likely to be needed anywhere else.

[mattkeys]

Replying to mattkeys:

Looking this over again, I think using an anonymous function here might be more appropriate to avoid needing the new callback function in /wp-includes/functions.php, since that function is not likely to be needed anywhere else.

It looks like anonymous functions only became available in PHP 5.3, and WP supports PHP 5.2.4, so I guess we cannot use the anonymous function version of my patch.

[nacin]

Hey mattkeys, we're still PHP 5.2.4+.

[mattkeys]

Replying to nacin:

Hey mattkeys, we're still PHP 5.2.4+.

Yea I realized right after submitting that second version of the patch that the anonymous function was not going to be available to us. Any thoughts on the first version I posted?

[boonebgorges]

I think we can probably do this without writing a new function. Let's just loop over the values and map maybe_unserialize() on them.

[mattkeys]

replacing array_walk_recursive with simple foreach

[mattkeys]

Replying to boonebgorges:

I think we can probably do this without writing a new function. Let's just loop over the values and map maybe_unserialize() on them.

Yea I was overcomplicating things here. New patch submitted.

[boonebgorges]

mattkeys - Yup, that's exactly what I had in mind. I'll write a couple unit tests for it and we'll put it in. Thanks for the contribution!

[boonebgorges]

In 30115:

Unserialize get_metadata() results when 'key' is omitted.

Props mattkeys, nacin.
Fixes #15030.

[dd32]

This is kind of obvious, but this is one thing that's worth noting is no longer backwards compatible (and affects,get_post_custom(), get_post_meta(), and get_metadata()).

If anyone was expecting a serialized string and passing it to unserialize() things will now break. If they were using maybe_unserialize() it will silently still work.

[johnbillion]

We're seeing breakage on WordPress.com VIP due to this change. Reopening to consider a revert.

[boonebgorges]

I'm fine with a revert if this is considered unacceptable breakage.

[johnbillion]

In 30701:

Revert r30115 which was a breaking change for code which interacts with the return value of get_metadata() when no meta key is specified.

See #15030

[johnbillion]

In 30702:

Update the tests for get_metadata() to reflect the revert in r30701.

See #15030

[johnbillion]

Wontfixing. If anyone comes up with a backwards-compatible way of doing this then by all means please re-open the ticket.

[mbelchev]

#38352 was marked as a duplicate.