WordPress MU

(Note: Donncha may want to look at this.)

I've been debugging a problem the last couple days, related to getting blog options from blogs other than the current blog. (Imagine widgets that render content from other blogs.)

What I noticed in debugging the code is that...

$val = get_option('foo');

...will access the "options" cache group.

While on the other hand...

$val = get_blog_option(1,'foo');

...will read from "site-options" cache group.

This seems like it could be a bug... as I assumed, and I think must plugin developers assumed that get_blog_option(1,'foo') would be the same as get_option('foo') from the blog_id=1 context.

In the old old old code (1.0 and earlier) get_blog_option() in fact did this, it would do a switch_to_blog() and then get_option().

As implemented today though, you could easily have someone setting/getting two different cache options that are out of sync.

Is this a bug? Should I report this on Trac?

Very nice spot, that's a bug for sure. I would make a trac ticket.

I know about this and it's intentional. There were cache poisoning issues when I tried to use the same cache in get_option() and get_blog_option(). Please open a trac ticket so this problem can be tracked properly.