Add limit 1 to get_blog_id_from_url

[spacedmonkey]

get_blog_id_from_url uses to get_sites to looks if site exists. But it only uses the first result. The param limit should be added to get_sites, limiting the query.

[danieltj]

Adds number parameter to limit by 1

[danieltj]

In 42073.diff, limits the query to get the first result from get_sites().

[flixos90]

We should consider simplifying the function further, by internally using the new get_site_by(). See https://core.trac.wordpress.org/ticket/40180#comment:24

• The advantage would be less code to maintain, and we could theoretically even deprecate this function at some point (not a necessity though).
• The disadvantage would be that get_site_by() returns a full object, while we only need an ID here. Not sure that's a real issue though, since it only queries for one result anyway, so it shouldn't have a significant impact on performance.

[jeremyfelt]

42073.2.diff​ uses get_site_by() and removes tests for blog-id-cache. If we go this route, we'll be able to remove blog-id-cache from a handful of other places as well.

[jeremyfelt]

As with #42072, I'm a little wary of the change in behavior here. Less so for get_blog_id_from_url(), but because we'll be removing blog-id-cache, I'd rather make the transition to get_site_by() earlier in a future release (5.0?).

Let's go with just the limit change for 4.9.

[jeremyfelt]

:facepalm:

[41736] has a commit message about domain_exists(), but that change was really for get_blog_id_from_url().

This ticket is fixed in [41736].