tree 5804a488126f94ac35e63589fd9b60adfc27a870
parent d30e00c240341e9e2a2d9519c67bd95fde906c7b
author Dmitri Shuralyov <dmitshur@golang.org> 1547063520 -0500
committer Dmitri Shuralyov <dmitshur@golang.org> 1547085536 +0000

godoc/redirect: display Gerrit/Rietveld CL disambiguation page when needed

For CL numbers that are determined to be Rietveld CLs, instead of
immediately redirecting, check whether a Gerrit CL with the same
number also exists. Do so by querying the Gerrit API and caching
the existing CLs. If both exist, display a very simple disambiguation
HTML page.

Cache Gerrit CLs that exist, to avoid querying the remote API server
more than once per CL. We can't cache Gerrit CLs that don't exist,
since they might get created in the future.

Fixes golang/go#28836

Change-Id: I08c32dc82a0136788337c5c32028e87428e8d81e
Reviewed-on: https://go-review.googlesource.com/c/157197
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>