Build 227 mounted Gemini and turned TestGeminiFiles::test_gemini_file_upload
red. litellm's two Gemini endpoints disagree about what api_base means.
Chat composes {api_base}/models/{model}:{endpoint} and defaults api_base to
https://generativelanguage.googleapis.com/v1beta, so the version lives
inside it. File upload composes {api_base}/upload/v1beta/files and defaults
to the host root, so the version lives outside it. A single api_base cannot
satisfy both, and a registration carries no signal about which endpoint the
deployment will be used for, so the edge cannot route one and not the other.
Backing it out rather than working around it. The cache must never turn a
passing test red, which is the same rule the Bedrock model allowlist
follows, and Gemini was 7 of roughly 1030 edge calls in that build. Anyone
pointing litellm's Gemini provider at an AI gateway or a corporate proxy
hits this too, so the fix belongs in litellm; mounting Gemini is one line
once it lands.
This reverts commit 8a553ceb58.
Build 226's 62 Bedrock rejections are the question this is trying to
answer, and "incomplete" would have covered both candidate causes at once.
Replaying the completeness rules over eight streams captured from live
Bedrock, covering tool use, extended thinking and a max-tokens stop on
both streaming endpoints, accepts every one of them, so a rule that is too
strict is the less likely half. A provider that answered 429 or 5xx and
was retried out of sight is the other, and it now counts as
rejected_error_status rather than being folded in with a grammar failure.
Build 226 routed Bedrock streaming for the first time and rejected 62 of
220 misses on that mount, and the counters could not say why. A flat
rejected count covers three unrelated things with opposite fixes: the
consumer walking away mid-capture, a body that arrived whole and failed
its endpoint's rule, and a provider that could not be reached. Each now
also counts its own reason.
A consumer that walks away was counting nothing at all. Abandoning the
capture generator raises GeneratorExit at its yield, so neither branch of
the old accounting ran and the miss simply vanished from the report, which
is also why misses could exceed writes plus rejected with nothing to
explain the gap. The decision moves into settle() so the generator's
finally owns the accounting and an abandoned capture is counted like any
other rejection.
Gemini needs none of the machinery Bedrock needed. litellm composes
{api_base}/models/{model}:{endpoint} from a custom api_base, so a plain
path-prefixed mount reaches it, and the credential travels as a static
x-goog-api-key header that no host rewrite invalidates. Nothing is
re-signed and nothing leaves the cache key, so a recording still cannot
cross credentials.
A finished turn names a finishReason on every candidate and reports
usageMetadata. The reason is read as a string rather than compared to
STOP: MAX_TOKENS and the safety reasons end a turn just as finally, and
rejecting them would send every one of them upstream forever. Streaming
is the half worth care. Gemini repeats usageMetadata on every chunk and
names a finishReason only on the last, so the terminator is the final
event rather than any event, and a stream the connection cut short ends
on a chunk carrying usage and no reason.
The mount's upstream base carries the API version, so the path the rules
see is /v1beta/models/..., not the one the proxy sent. The first version
of this anchored the rule at the start of that path, which passed every
test against a stub with no version prefix and would have cached nothing
at all in a real run. Caught by replaying the rules over responses
captured from live gemini-2.5-flash, which is also why the tests now
mount their stub under the version prefix.
Vertex stays unmounted and is a separate provider here: litellm grafts
the default Vertex path onto an api_base only when that api_base has no
path of its own, so Vertex needs a root-mounted edge on its own port.
The Claude Code compat cells drive the real CLI, which always streams, so
converse-stream and invoke-with-response-stream were most of the suite's
Bedrock traffic and all of it bypassed the edge.
AWS frames those as binary vnd.amazon.eventstream rather than SSE, so
botocore's own parser reads the frames and validates both CRCs, and each
endpoint is then held to its terminal grammar. Two details drove the rule.
A ConverseStream ends with metadata, not with messageStop, and metadata is
what carries the token usage litellm prices the call from, so a stream cut
between the two names a stop reason but would replay as a free call. And a
dropped connection is invisible to the parser: it yields the frames it did
receive and silently discards a trailing partial one, so a stream cut one
byte short parses clean. The body is checked against the frame lengths it
declares to catch that.
The invoke stream carries the ordinary Anthropic event grammar inside its
chunk frames, so it shares the completeness rule with the SSE mounts.
Validated against three real Bedrock eventstream captures, and the tests
build their own frames rather than pasting a capture, with one test holding
that framing to botocore's parser.
