commit 2bbec900f1cb31ff9a8312188d3ae82433d080dc
author Vadim Shtayura <vadimsh@chromium.org> Tue Oct 08 01:19:30 2024
committer LUCI CQ <infra-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Oct 08 01:19:30 2024
tree 6aeea8f4970e31942c52f2f373b36967b5ee0ad1
parent efe7de00f4f652709094112168b47be362aaef94

[auth] Refactor GCE metadata emulation.

Previously we were emulating a bunch of very specific HTTP
calls that various tools are making. This required to
occasionally touch this code to add another way some new tool
queries metadata.

Instead this now implements most of the GCE metadata protocol
with all its quirks, but we populate only subset of metadata
that is actually expected to be used. This better covers all
the ways various tools interact with the metadata server.

There's also a change to "instance/name" and "instance/zone".
Before, they were exposed only when running on real GCE and
values were taken from the real GCE metadata when starting
the server.

Now "instance/name" is always exposed (but set to the
machine hostname when on non-GCE), and "instance/zone" is
queryable only on real GCE. "Proxying" to real GCE metadata
happens lazily, removing the need for AssumeNonGCE hack.

This was needed to make sure "instance/" listing works, since
"gcp-metadata" npm packages uses its presence to detect GCE
environment.

BUG=b/370833648
R=iannucci@chromium.org

Change-Id: Ia5286535bf980aa6391229038330c39a71b61a04
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/5906463
Reviewed-by: Robbie Iannucci <iannucci@chromium.org>
Commit-Queue: Vadim Shtayura <vadimsh@chromium.org>