Activity Meta doesn't recognize 0 as a valid value

[saurabhshukla]

A meta key not existing and a meta key with a value of 0 are two different things and this distinction can be useful at times.

I attempted storing a privacy meta as 0 and I could never check for it. I wanted to distinguish between activities that have a deliberate privacy set to 0 and activities that never had any privacy set.

Can't do that anyway I tried, so I had to set it as -1 which makes me do extra bending around. This is in contrast to how WordPress post meta is stored and retrieved.

In fact I was mapping posts to activities and also mapping the corresponding metas.

The empty() check in the meta functions is the culprit. Are we open to replace this approach with something else?

[r-a-y]

Don't use an empty check.

Use a strict comparison check.

Like:

// check if meta is integer 0
if ( $meta === 0 ) {

See if that works for you.

I'm closing this because this doesn't sound like a bug with BP. But do feel to continue posting to see if what I stated works for you or not.

If it does end up being a BP problem, I'll reopen.

[saurabhshukla]

I'm not the one using a check. BuddyPress checks for empty($activity_meta) and hence I can't use 0 as a value for meta. As soon as I get my hands off rtMedia, I'll submit a patch.

in function bp_activity_update_meta() in bp-activity-functions.php

if ( empty( $meta_value ) )
		return bp_activity_delete_meta( $activity_id, $meta_key );

should've been

if ( $meta_value===false )
		return bp_activity_delete_meta( $activity_id, $meta_key );

If I try and store 0 as a value, the key gets deleted, offsetting the architecture of the code that I'm trying to write.

In fact, I don't see the sense in this code, even with the strict comparison. If I pass a false value for a meta (which could also be legitimate), the key itself gets deleted.

Hope, I've come across more clearly this time.

[boonebgorges]

saurabhshukla is correct that this is an issue. See #3139 for the corresponding report in the Groups component.

I don't mind putting in a fix for this particular issue, though it will require a once-over of the codebase to make sure that we're not breaking anything. I'll put this in the 1.9 milestone as a preliminary measure.

Also related: #3907, which proposes turning our custom meta functions into wrappers for update_metadata(), etc.

[r-a-y]

I'm not the one using a check. BuddyPress checks for empty($activity_meta) and hence I can't use 0 as a value for meta.

Good call, saurabhshukla. I should have looked through the codebase before posting!

[boonebgorges]

In 7576:

Allow 0 to be stored in activitymeta

Previously, any value where empty( $value ) evaluated to true would result
in the deletion of the row. This change allows for 0 to be stored as a
legitimate value.

This is a stopgap until BP's meta functions are refactored to use WP's core
*_metadata() functions.

Fixes #5083