[vaind]

Sentry's git endpoint (getsentry/sentry#128444) relays git requests through GitRelay with Sentry's BlacklistAdapter, so a GitHub Enterprise or self-managed GitLab host that resolves to an internal address is refused. The adapter refuses by raising Sentry's own RestrictedIPAddress. scm doesn't know that exception, so GitServer counts the refusal as unhandled_exception and re-raises it, and Sentry's view has to catch, report and answer it itself.

Approach

• GitRelay(map_error=...) takes a function that gets an exception from the upstream request and returns either a coded error to raise in its place or None to let the original through unchanged. scm can't import Sentry's exception, so the caller decides which of its adapter's errors mean what. Without a mapper, nothing changes.
• The relay's own handling runs first: requests and urllib3 exceptions still become ResourceGatewayTimeout, ResourceServiceUnavailable and the rest, and the relay's own coded errors (such as the client going away mid-body) pass straight through. So the mapper never sees an exception that holds the Authorization header, and can't relabel those.
• A mapped error is raised from None. A refusal raised as urllib3 connects has a traceback that runs through urllib3 frames holding the Authorization header.
• New coded error GitRemoteRefused (git_remote_refused) for a refused host. Its message doesn't name the host or address, like the relay's other errors.
• GitServer answers it with a 502, next to git_remote_not_https, the other remote the relay won't connect to. A 503 there means "temporarily unavailable, the request can be retried" (resource_service_unavailable), and retrying a refused host never helps. Sentry answers this case with a 503 today; after the bump it becomes a 502.

Usage, for an adapter that refuses with HostRefused:

GitRelay(adapter=..., map_error=lambda e: GitRemoteRefused() if isinstance(e, HostRefused) else None)

Tests

A test adapter refuses the way BlacklistAdapter does, from inside urllib3's connect.

• Mapped, the refusal becomes GitRemoteRefused with no cause, a suppressed context, and neither the token nor the address. GitServer answers it with a 502 and counts git_remote_refused rather than unhandled_exception.
• With no mapper, or a mapper returning None, the original propagates as raised.
• A requests error, a urllib3 error and the relay's own client_closed_request never reach the mapper.

Dropping from None, the _STATUS entry or the pass-through of the relay's own errors, or calling the mapper before the requests handling, each fails a test.

After release

feat makes this a minor release. Sentry's bump PR then passes map_error=lambda e: GitRemoteRefused() if isinstance(e, RestrictedIPAddress) else None in make_git_server() and drops the view's own except RestrictedIPAddress branch.