The Charts view could break usage down by user, group or total, but not
by model. Per-model data existed only as day-window attempt and failure
counts, which measure availability rather than delivered usage.
A served model now accumulates the same four metrics a user or group
does. The scope kind is "model" and its id is the canonical
"provider/model", so a request that fails over counts against the
provider that answered it, and one bare id served by two providers ranks
as two rows.
The request counter is written after the response, in the batch that
already writes tokens and cost. That is the first point at which the
serving model is known, so no extra round trip is needed and admission
never double counts.
GET /admin/api/usage/models ranks models for one metric and window. It
returns only models with non-zero usage, by operator requirement: the
catalog runs to hundreds of models and a padded ranking is unreadable.
The read stays one storeGetMulti over the catalog.
The Charts view gains a Models tab with its own metric picker, and the
scope picker gains the models that have traffic.
bareWinner picked the first provider in global sorted order that served
a bare model id, ignoring which providers the caller's group could
actually use. resolveAgainst then denied the request whenever that
provider fell outside the group, even when another provider serving the
identical id was already permitted. A caller entitled to a model could
receive errModelDenied purely because an unrelated, invisible provider
sorted first alphabetically.
bareWinner now takes the group and prefers the sorted-first provider it
may use, falling back to the global sorted-first provider only when the
group is authorized for none of them. That fallback keeps a genuinely
unauthorized request returning errModelDenied, not the wrong
errModelUnknown a "no visible owner" result would produce. resolve,
resolveAliasTarget, and the alias-shadow collision check all route
through this corrected selection.
listFor now computes each bare id's owner from the group's own visible
providers and adds "provider/model" disambiguating entries only when the
group can see two or more owners of that id. A provider invisible to the
group never appears in that group's catalog, bare or prefixed.
warnCollisionOnce keeps logging the global collision unchanged, since a
provider collision is a fact about the fleet's configuration that every
operator must see regardless of which group lists models first. Its
message now says winner is the global default, because a group's own
request can resolve to a different provider than the one logged.
Adds registry_test.go coverage for the production repro, the
both-allowed and neither-allowed non-regression cases, the listing
behavior, and the alias path. Adds a yaegi-check probe proving the fix
resolves and serves under the real interpreter, and updates one existing
listFor test that asserted the pre-fix prefixed-form behavior.
The README claimed discovery runs again on discoveryInterval "in the
background", which reads as a periodic timer. There is none. maybeRefresh
is called from ServeHTTP only, so the interval is checked per incoming
request and a refresh is spawned when it has elapsed.
That distinction is what an operator actually needs, because it has three
consequences the old wording hid: an idle gateway never refreshes at all,
a newly published upstream model takes up to discoveryInterval to appear,
and there is no manual trigger since the admin API is read-only.
The plugin runs inside the Traefik process, so declining to start a
periodic goroutine is deliberate rather than an oversight. Documented as
behaviour, with the option of lowering discoveryInterval on the providers
whose catalogues actually change. Also corrected the two provider config
table rows that carried the same implication. Documentation only.
The federated /mcp endpoint ignored the Accept header and always
returned application/json. A real MCP client that sends Accept:
application/json, text/event-stream expects SSE framing. It fails with
no data line in SSE response when it receives plain JSON instead.
handleMCPFederated now negotiates the response format once per request
from the Accept header. It threads the result through
writeJSONRPCEnvelope, writeJSONRPCResult, and writeJSONRPCErrorResponse
as an explicit parameter. A request with no Accept header, or one that
omits text/event-stream, still gets byte-identical plain JSON. Only an
explicit text/event-stream token in the Accept list switches the
response to SSE framing. SSE framing is one data line carrying the
JSON-RPC envelope, terminated by the required blank line.
Error responses and every method path honor the negotiated format.
Notification responses stay 202 with no body regardless of Accept.
The SSE branch reuses sse.go newSSEWriter and writeData instead of a
second encoder. writeData already writes the single-frame, correctly
terminated shape this route needs.
Adds a compiled test file with a captured pre-change JSON byte
baseline. It also adds explicit SSE negotiation and framing tests. A
new yaegi-check probe exercises both framings under the real
interpreter.
Add a provenance-est provider whose upstream answers with no "usage"
field at all, driving a real, non-streaming chat completion against it
under Yaegi. exerciseUsageProvenance then parses GET /metrics with the
real Prometheus TextParser and confirms both new families
(llmgateway_usage_provenance_requests_total and
-_tokens_total) render as COUNTER type with a distinct "estimated"
series for this provider and a distinct "reported" series for openai's
own already-driven traffic, then confirms GET /admin/api/overview
surfaces the identical estimated observation and never leaks a
"reported" key into the compact admin summary.
Run at the end of run(), after every other probe that already reads
/metrics or /admin/api/overview, so it never perturbs a counter an
earlier probe asserted on.
Rebuilds webui/dist/ via vite build and re-runs webui/generate.mjs to
bake the usage-provenance badge changes into admin_assets_gen.go, the
file admin.go's serveAdminPage/serveAdminAsset actually serve.
Add AdminProvenanceView and AdminProviderView.provenance to types/api.ts,
mirroring admin.go's new fields, then surface two badges beside the
existing health and latency badges in ProvidersView.vue: "estimated N"
(secondary variant) and "unbilled N" (destructive variant), each with a
hover title explaining what happened and why it matters. Neither badge
renders when that provenance kind has no observations yet, matching the
existing health/latency badges' own convention.
Estimated and unbilled stay two separate badges, never merged into one
indicator: collapsing them would hide the one thing this feature exists
to surface, that a provider serving completions entirely free against
every budget is a materially different failure than an approximated
bill.
Built with shadcn-vue's existing Badge component; no hand-rolled markup.
Add adminProviderView.Provenance to GET /admin/api/overview: a compact,
per-provider map keyed by provenance kind, populated only for
"estimated" and "unbilled" observations. "reported" never appears here,
since it is the healthy default and AttemptsDay/FailuresDay already
describe it; the full reported/estimated/unbilled breakdown, by request
and by token, stays on GET /metrics.
buildAdminProvenanceViews mirrors buildAdminLatencyViews' own shape:
one batched g.provenance.snapshot() read per response, grouped by
provider, so this adds no additional store round trip and keeps the
already-large overview response small, matching the existing latency
summary's own size budget.
A test proves the reported/estimated/unbilled filtering, verified
against a real mutation of the exclusion guard before being kept.
Token accounting has three provenances today: reported (real provider
usage), estimated (a non-streaming response with no usage, prompt
substituted from request body size), and unbilled (a streaming response
with no usage, request counted but zero tokens billed). Nothing on any
read surface distinguished them before this change.
Add a per-process provenanceStore (metrics.go), recorded in
runUnified right after the existing estimated/unbilled classification
(routes_unified.go), for a candidate whose response actually completed.
A failed-over candidate is never recorded, so ordinary failover noise
never pollutes the unbilled signal.
Expose two new counter families on GET /metrics:
llmgateway_usage_provenance_requests_total and
llmgateway_usage_provenance_tokens_total, both labeled by provider and
provenance. Together they answer the three operator questions this
change targets: what fraction of billed tokens came from real reported
usage, which providers produce estimated or unbilled accounting, and
how often the unbilled case happens at all. Both families are
in-process only, so sum() is the correct cross-replica aggregation,
matching this file's other per-process families.
Billing itself is unchanged: this only records which provenance an
already-billed number took, never a new number.
Tests cover reported/estimated/unbilled classification, that billing
matches the pre-existing contract exactly, and that estimated and
unbilled never collapse into one series. Each behavioral assertion was
verified against a real mutation of the source before being kept.
Add streaming and non-streaming latency badges beside the discovery
health badge on each provider row. Streaming shows average time to
first byte, labeled ttfb, since it is the only load-sensitive figure
this data provides. Non-streaming shows average total duration,
labeled avg, never latency or ttfb, because a non-streaming provider
buffers the whole completion before sending anything and its ttfb
carries the same output-length contamination as its duration.
Badges omit entirely when a provider has no observations yet, so
absence never reads as a fabricated zero. Every badge title states the
per-replica, in-process scope explicitly: this data comes from the
same in-process accumulator the rate-limit counters use, never Redis,
so a single poll reflects only whichever replica answered it.
Mirror admin.go's adminLatencyView type in types/api.ts, keyed by the
literal streaming/non-streaming union admin.go emits. Add
formatLatencyMs to lib/format.ts with spec tests alongside its
siblings in format.spec.ts.
Add exerciseLatencyMetrics, proving the new upstream-latency histograms
render correctly under the real Yaegi interpreter, not merely that a
compiled go test accepts the same bytes. Compiled tests have repeatedly
passed on this codebase while the interpreted shape failed, which is
exactly what this probe caught: two bugs in the core feature commit,
found and fixed only because this harness exists.
Parse the rendered body with prometheus/common/expfmt's real
TextParser, the same library a real Prometheus server's scrape loop
uses, instead of this project's own hand-rolled parser. A malformed
histogram fails to parse outright under a real parser, matching the
failure mode a live scrape target actually hits, rather than merely
failing one hand-written assertion.
No new traffic is driven here: the existing exerciseAttemptAccounting
sub-probe already posts one real, non-streaming chat completion against
the openai provider, so the duration histogram already carries a real
observation by the time this probe runs.
Add github.com/prometheus/common/expfmt as a dependency of this
harness module only, isolated from the plugin's own stdlib-only go.mod
by design (this package's own doc comment). Go raised this module's go
directive from 1.22 to 1.25.0 to satisfy the new dependency; the
plugin module itself is untouched.
Add time-to-first-byte and total-duration histograms for every upstream
call, observation only. No throttling, priorities, or control logic
reads this data. The operator wants strain-based throttling later and
needs real traffic data first.
Extend watchdogBody (timeout.go) rather than add a new interception
layer: it already wraps every upstream response body for provider
adapters, native passthrough, and the MCP/A2A target proxy, and already
observes the first successful read. armLatency arms a watchdogBody
after construction, so newWatchdogBody keeps its existing signature and
behavior; its own pinned tests still pass unchanged. A timestamp plus a
few atomics are the only added cost; Read and Close each pay one nil
check when latency collection is disabled.
Expose llmgateway_upstream_ttfb_seconds and
llmgateway_upstream_duration_seconds on the existing Prometheus
endpoint (metrics.go). Both are in-process, per-replica histograms,
never store-backed, so sum() is always the correct cross-replica
aggregation. Buckets run 0.1s to 600s, chosen to resolve fast TTFB and
short completions finely, cover the bulk of real chat completions, and
bracket the five-minute default request timeout. Labels are provider
and stream always, model only when Config.Metrics.ModelLabel is set,
matching the existing per-model opt-in convention. Add a compact
per-provider, per-stream average summary to GET /admin/api/overview,
sourced from the same in-process store, without a full histogram or a
per-model breakdown.
Every write path is gated on metricsEnabled(cfg), so a deployment with
metrics disabled collects nothing and the histogram families never
render. No behavior change to request handling: same responses, status
codes, headers, and accounting.
Fix a Yaegi-only bug this feature's own context-threading change
exposed: two distinct empty struct types used as context.WithValue keys
compare equal to each other under the interpreter's interface equality,
though never under compiled Go. Threading a second recorder
(latencyRecorder) alongside the existing attemptRecorder made this
observable for the first time, since compiled tests never see it and
the plugin previously carried only one such key. Give
latencyRecorderCtxKey a field so its size differs from
attemptRecorderCtxKey's, confirmed against a minimal Yaegi reproduction
before and after the fix.
Fix a second bug, reproducible under compiled Go too: io.Reader may
legally return its final data together with io.EOF in one call, and
Go's real net/http body reader does this for small, fully-buffered
responses. The original TTFB capture lived inside the err == nil
branch, so it never fired for a typical small non-streaming completion.
Move the check ahead of the error branch so it fires on any n > 0,
leaving the pinned timer-reset and Close semantics untouched.
Tests mutate the real source per case and confirm each one fails first,
recorded in each test's own doc comment.
The Traefik Plugin Catalog analyzer rejected v1.0.43:
import "github.com/lukaszraczylo/oss-telemetry" error:
unable to find source related to: "github.com/lukaszraczylo/oss-telemetry"
piceus fetches the source archive at the released tag and interprets it
with Yaegi. It never runs go mod download, so every non-stdlib import in
production code must exist in the archive own vendor/ tree.
.gitattributes carried "vendor/ export-ignore" with an explicit warning
to remove it the moment production code imported a third-party package.
That happened when llmgateway.go took on oss-telemetry for anonymous
usage reporting, and the warning was missed. The tag itself always had
vendor/; git archive stripped it, so the tarball shipped a go.mod
requiring a module whose source was absent.
Verified by reproducing the analyzer: the v1.0.43 archive contains 0
vendor entries, the fixed archive contains 71, and interpreting the
extracted archive under yaegi passes.
F2: the idle timer resets on DECODED body bytes, after net/http's own
gzip decompression. A gzip'd response whose compressed bytes arrive
steadily but whose deflate stream yields nothing for the whole window
still gets aborted. The previous wording claimed a slow-but-progressing
body is always unaffected; adds a qualifying paragraph explaining the
gzip case and why fixing it (measuring wire bytes) is out of scope at
the five-minute default.
F3: reworded the "silence ends a request, never elapsed time" framing.
A streaming forwarder reads a chunk, writes it to the client, then
reads again; the write is not watched, so time blocked on a slow
client counts against the same idle window as a silent provider.
Aborting is still correct, but the log line no longer claims the
provider specifically caused it.
F5: documents that neither timeout is ever retried, and why: a
ResponseHeaderTimeout failure wraps context.DeadlineExceeded, which
Retry's own transient classification excludes; a mid-body watchdog
timeout fires after the retry mechanism has already returned.
F8: softened "Every upstream request this gateway makes" to the
routes actually covered, and added a "Federated MCP" note: the
federated /mcp endpoint's two direct calls are not wrapped by the
idle-progress watchdog, but are not unbounded either — they still get
ResponseHeaderTimeout from the shared client, plus their own 20s/120s/
5s context.WithTimeout budgets. Worst case is a bounded stall, not a
forever one.
exerciseRequestTimeout only drove a provider that never sends headers,
so it exercised Transport.ResponseHeaderTimeout alone.
watchdogBody.fire — the interpreted method value handed to
time.AfterFunc, plus context.CancelFunc and sync/atomic's function API
— never ran under that probe, since the request never got far enough
to construct a watchdogBody at all (finding F7, coordinator
adversarial review, 2026-08-23).
Adds hungbody, a provider whose upstream sends headers immediately and
then stalls, and exerciseRequestTimeoutMidBodyStall to drive it.
Verified the two probes exercise different code paths: removing
watchdogBody's construction from upstreamBytes left the existing
header-timeout probe passing unchanged, while the new probe failed
with status 200 instead of 502. Reverted before this commit.
F1: TestModelRegistry_MaybeRefresh_Throttled_OnePerInterval mutated a
plain `now` variable while a background refresh goroutine read it
through nowFn, racing under -race in about 14% of full-suite runs once
this branch's timer-heavy tests shared the parallel phase. Guards the
clock with a mutex instead. registry.go is untouched.
F4: a mid-body watchdog timeout never reached provider-health
accounting. limiter.recordProviderAttempt only ran at header-arrival
time, so a provider that reliably stalled mid-body reported
attempts=1 failures=0 forever. watchdogBody.fire now invokes the same
attemptRecorder a second time, as a failure, when it fires. Reuses the
existing recorder rather than adding new plumbing; this does mean two
attempts are recorded for one logical request (one success at header
time, one failure at watchdog-fire time), not one attempt marked
failed outright.
F6: watchdogBody.Read reset the timer on any err == nil read,
regardless of n. A reader returning (0, nil) forever would have held
the watchdog open indefinitely. Reset now only fires when n > 0.
F9 (three items):
- proxyUpstream passed logPrefix as a bare providerName, which
newWatchdogBody wrapped in a hardcoded `provider %q` — labeling an
MCP/A2A target as a provider. watchdogBody now takes an
already-formatted label from the caller instead.
- errUpstream was wrapped twice: once in watchdogBody's own error, once
again by every caller that already wraps it. watchdogBody now wraps
only errProviderTimeout; callers' existing wraps still make
errors.Is(err, errUpstream) hold.
- timeout_test.go read wb.timedOut directly in one place while every
other access is atomic; switched to atomic.LoadInt32.
Also rewords errProviderTimeout's message from "provider request timed
out" to "upstream progress stalled" (finding F3, documented not fixed
per coordinator ruling): the watchdog measures time since the last
successful upstream read, which can go quiet because of a slow client
write between reads, not only a slow provider. The new wording no
longer asserts which side caused it.
New tests: TestChatCompletion_Stream_StallsMidBody_RecordsProviderFailure,
TestWatchdogBody_ZeroByteRead_DoesNotResetTimer,
TestWatchdogBody_TimeoutError_UsesCallerLabel_NotHardcodedProvider.
Each mutation-verified per its own doc comment.
The VMServiceScrape example scraped Traefik's pods directly, so the
request carried Host: <pod-ip>:<port>. Traefik evaluates a router's
match rule before any middleware runs, and the only router in this
file requires Host(`llm.example.com`). The scrape request never
matched it, the llmgateway middleware never ran, and /metrics 404ed
before the plugin ever saw the request.
Add a second, Host-free IngressRoute matching PathPrefix(`/metrics`)
and carrying the same middleware, so an in-cluster scraper reaches the
route regardless of what Host header it sends. Document the
reachability trade-off this introduces (this route is not
Host-restricted, though /metrics stays gated by its own auth inside
the plugin) and name the alternative fix the review also offered:
relabelConfigs rewriting __address__ to the ingress hostname before
the request is sent, keeping one Host-scoped router instead.
Three blocking fixes from a second round of adversarial verification,
plus two should-fix items bundled in since they touch the same code.
storeDown detection covered only the fail-CLOSED path. failOpen
defaults to true (newConfiguredLimiter), so on the shipped default a
broken store made storeGetMulti return ok=true after silently reading
the empty in-process fallback, bypassing every storeDown guard in
metrics.go. Add limiter.configuredStoreDown, checked alongside ok in
currentUsage and providerUsage, so a fail-open read served from the
fallback is treated the same as a fail-closed refusal. The pinning
test previously hand-set failOpen=false, which meant it only ever
exercised the case that was already correct; it now leaves failOpen at
its true default.
The escaping rewrite from the previous round achieved injectivity by
copying an invalid UTF-8 byte through raw, which can make the output
itself invalid UTF-8. Measured against a real Prometheus scrape parser
this round: invalid UTF-8 in a label value is fatal, the scrape target
goes down, which is worse than the duplicate series the previous round
was fixing (measured non-fatal, dropped and logged, target stays up).
Replace an invalid byte with a deterministic \xHH marker instead,
proven injective and always valid UTF-8 by an exhaustive test over
every 1- and 2-byte input, not merely spot-checked. Also adds the fast
path a benchmark showed the byte-oriented rewrite needed: unescaped,
already-valid-UTF-8 input, the common case, returns unchanged with
zero allocations instead of paying a full copy.
llmgateway_rate_limit_rejections_total's HELP text claimed it "resets
only on restart", which stopped being true once the previous round
added generation-rotation bounding and reload-triggered eviction: a
scope resets when its user is removed, and every tracked scope resets
together in bulk the instant the tracked-scope cap is exceeded. The
HELP text and README now say so.
Adds llmgateway_limit_store_up, a per-replica gauge for this process's
own connection health to the configured limit store: with the store
flapping faster than its fail latch, every store-backed family can go
silent scrape after scrape with nothing on the endpoint itself saying
why. Also adds a test pinning that Gateway.pruneRejectionsAfterReload
runs only when authStore.maybeReload reports a real reload, never on
every request.
Fix one must-fix and one should-fix finding from re-verification of
d45125e, plus two smaller findings from the same pass.
MUST FIX: the F2 header clear ran on the first candidate attempt too,
so it ran on the default, failover-disabled path and deleted response
headers a different, earlier Traefik middleware had already staged
before this plugin ran (CORS, HSTS, request-id, and similar). Scope the
clear to i > 0, the only case that ever needs it. Add a test proving a
header staged before the gateway runs survives the default path, on
both a cache hit and a cache miss.
SHOULD FIX, coordinator ruling: drop the all-candidates cache pre-pass.
It silently served a different candidate's cached response while the
primary was perfectly healthy, which is failover with no failure. Check
each candidate's own cache entry immediately before that candidate's
own attempt instead. Request-path health, now fixed in the prior round,
is the correct mechanism for skipping a genuinely dead primary: once it
is marked unhealthy it is excluded from the candidate list entirely, so
a later request still reaches the next candidate's cache without the
dead one being dialed. Update the existing cache regression test to
drive enough requests to trip the health breaker before asserting no
repeat call, and add a dedicated test proving a healthy primary is never
bypassed for another candidate's cached response.
Guard the request-health record call with the enabled check. That state
is never read on the disabled path, so recording it there was dead work
plus a new contention point on requestHealthTracker's tracker-wide mutex
on every metered request, disabled or not. Add a test asserting the
tracker's internal state stays empty across the disabled path.
Add a test proving the 404 loud-log line is not rate-limited: drive two
404 failovers through the same Gateway in one request and assert both
lines appear, since a version that wrapped the 404 line in the same
rate limiter as the generic line would still pass every other test
(each of which only ever drives one 404 event against a fresh gate).
Document, but do not fix, that the cost guard cannot see a model
declared free via modelMeta: it resolves pricing only through the same
source real billing uses (pricing and the built-in table), which is
correct and consistent, but means an operator who declares a model free
the modelMeta way loses it as a failover candidate without realizing
why. README now says to use pricing instead for that case.
Every fix is proven by a dedicated regression test, and each was
verified by reverting the fix in place and confirming the corresponding
test fails before restoring it.
Adds a "Request timeout" section explaining the progress-based design,
the two mechanisms, the global/per-provider override rule, and error
classification. States plainly that this changes behavior for every
deployment, since no timeout existed before.
Adds requestTimeout rows to the Config and ProviderConfig reference
tables.
Adds exerciseRequestTimeout: a provider (hungtimeout) with an 80ms
ProviderConfig.RequestTimeout, backed by an upstream that stays silent
for 600ms. The request carries no client-side deadline of its own, so
a pass proves the gateway's own adapter-level timeout aborts the hang,
not a caller-supplied context.
This complements the existing slowProviderName probe, which proves a
CLIENT-set deadline classifies correctly. It does not prove the
adapter's own timeout mechanism runs correctly interpreted, since it
never exercises it without client help.
Verified the probe is not a no-op: temporarily removing
Transport.ResponseHeaderTimeout from newAdapterHTTPClient made make
yaegi-check fail with status 200 instead of 502. Reverted before this
commit.
timeoutProviderModel uses a distinct id, not testDataWantModel:
reusing it made the new provider win bare-id model resolution and
silently hijacked an unrelated existing probe.
TestWatchdogBody_NoBlockingGoroutineLeak_AcrossManyRequests drove its
timed-out iterations against a server that never wrote headers. That
hits Transport.ResponseHeaderTimeout inside client.Do and returns
before a response ever exists, so watchdogBody.fire never runs and the
test could not have caught a leak in fire itself.
The mutation-verification pass (manually adding a permanently blocked
goroutine to fire, then reverting) confirmed this: the test passed
even with that goroutine present. Fixing the stalling server to write
headers first, mirroring the mid-body-stall tests above it, makes
fire run on every iteration. Re-running the same mutation now fails
the test as intended.
Adapters previously issued upstream requests with no timeout at all.
A provider that accepted a connection and then stalled hung the
gateway request forever. newAdapterHTTPClient now sets
Transport.ResponseHeaderTimeout, and every response body read
(providers.go's upstreamBytes, routes_passthrough.go's proxyUpstream)
runs through a watchdogBody that resets on every successful read and
cancels the request once timeout passes with no progress.
The idle-progress design lets a long stream that keeps emitting tokens
run indefinitely. Only silence, never total duration, ends a request.
Config.RequestTimeout sets the global default (five minutes when
unset). ProviderConfig.RequestTimeout overrides it per provider. Both
are Go duration strings, validated at construction; a zero or negative
value is rejected rather than treated as unlimited, since that would
reintroduce the hang this feature fixes.
Native passthrough (routes_passthrough.go) and the MCP/A2A target
proxy (mcp_a2a.go) share the identical watchdog mechanism through
proxyUpstream's new timeout parameter.
A watchdog-fired timeout wraps errProviderTimeout and names the
provider. It never wraps context.Canceled, so it stays distinguishable
from a genuine client disconnect in every existing log classification.
Flip FailoverConfig.Enabled to default false. A version upgrade with no
config change must preserve prior behaviour, and failover changes which
provider serves a request. Update tests, README, and the yaegi-check
probe to opt in explicitly.
Add a mandatory cost guard. A candidate is skipped unless its input AND
output cost per token are each no greater than the primary candidate's,
resolved through the same canonical-then-bare pricing path the real
billing code uses. Unknown pricing is never treated as free: a known
primary against an unknown candidate skips, an unknown primary against a
known non-zero candidate skips, everything else that is equal is
allowed. Not configurable.
Fix four blocking findings from adversarial review of commit 5d62479.
F1: openai-type adapters mutate the request map in place to force
stream usage reporting. Reusing one map across candidates let a later
candidate read back an earlier candidate's own injection and leak a
usage-only SSE chunk to a client that never asked for it. Every
candidate now attempts against a fresh copy of the original request.
F2: a streaming candidate that fails before writing anything still
stages SSE-only response headers. Those headers now get cleared before
every candidate attempt, so they cannot survive into a later
candidate's plain JSON response.
F3: the request-health gate used the retry-shaped isTransient
classification, which treats a non-429 4xx as a successful outcome. A
provider with a dead API key was never skipped and was retried forever.
The gate now reuses failoverEligible's own classification instead.
F4: a shared request context that an earlier candidate exhausted was
attributed to whichever candidate happened to run next, opening a
healthy provider's breaker for a timeout that was not its fault. A
candidate is no longer attempted once the shared context is already
done; the loop stops and reports the last real error instead.
Also fix three should-fix findings from the same review.
F5: a failure arriving while the request-health breaker is already open
but not yet past its cooldown window is now a no-op, instead of
resetting backoff and sliding the open window forward on every such
failure.
F6: the request-health gate now records at most one outcome per
candidate per logical request, not one per same-provider retry attempt,
so retry.attempts alone can no longer open the breaker on a single
request.
F7: every candidate's cache entry is now checked before any candidate
is attempted, so a cached failover response no longer costs a round
trip to a still-broken primary first.
F10: the generic "failing over" log line is now rate-limited to once
per 30 seconds during a sustained outage, reusing the existing logGate
type. The 404 loud-log line stays unthrottled, as ruled.
F9 (optional): skip building the failover candidate pool entirely when
failover is disabled.
Correct an overstated test comment on
TestHandleChat_Failover_DiscoveryUnhealthy_StillTried: it proves alpha
is still tried, not that ordering places it second.
Document, but do not fix here, that this plugin's HTTP client sets no
per-attempt timeout, so a provider that accepts a connection and then
hangs will never trigger failover. This is a pre-existing property of
the shared HTTP client, not specific to failover.
Deferred: F8 (surfacing request-health state on the admin dashboard)
touches admin.go, which a sibling branch is also editing concurrently;
left for a follow-up to avoid a merge conflict in a file this change
does not otherwise need.
Every fix above is proven by a dedicated regression test, and each was
verified by reverting the fix in place and confirming the corresponding
test fails before restoring it.
The metrics feature shipped in code only: no README section, no
metrics block in .traefik.yml testData, nothing under examples/. The
Go doc comments were the entire manual for a human operator or a
config-generating assistant.
Add a README Metrics section covering the served path, both auth
modes (admin bearer token, optional CIDR allowlist), the CIDR-sizing
warning with the live-reproduced SNAT failure mode, the modelLabel
cardinality trade-off, the exposed metric families, the cross-replica
aggregation contract, label escaping, and store-outage behaviour. Add
a MetricsConfig reference table matching the existing AdminConfig
one, and a metrics row in the top-level Config table.
Add metrics: {enabled: true} to .traefik.yml's testData, the
catalog-facing smoke-test config, deliberately without allowedCIDRs
so a copy-pasted example never skips the README's own sizing
guidance.
Add a metrics block to the Kubernetes Middleware example and a
VMServiceScrape resource: the target cluster runs VictoriaMetrics, not
Prometheus, so the CRD differs even though the exposition format does
not. Verified the VMServiceScrape shape (apiVersion, selector,
endpoints, path) against the victoriametrics/operator documentation
rather than assuming it. Notes that /metrics is served by Traefik
itself, not by any backend service, since this middleware intercepts
the path before a backend is ever reached.
Add a third configured user whose name contains a double quote, a
backslash, and a newline, then assert GET /metrics renders its
Prometheus-escaped form and never the raw name. auth.go validates a
user name as non-empty only, so this is a real, legal configuration,
not a contrived one.
The compiled suite already proves escapeLabelValue correct
(TestMetrics_LabelValuesWithSpecialChars_Escaped,
TestEscapeLabelValue_InvalidUTF8_Injective), but this codebase's own
history is that a compiled pass has repeatedly said nothing about the
interpreted shape. json.Marshal produces the JSON-escaped literal for
the harness's own hand-built config document, kept separate from the
Prometheus escaping the probe actually verifies in the rendered body.
Three fixes from adversarial verification.
writeProviderMetrics rendered a storeDown providerCounters entry as a
hard zero, the same fabricated-reset hazard the request/token/cost
families already guarded against. Skip a storeDown provider or
provider-model entry instead of emitting it.
escapeLabelValue ranged over the string as runes, and Go substitutes
U+FFFD for every invalid UTF-8 byte. Two distinct configured names
that both contain invalid UTF-8 could therefore render as the
identical escaped value, colliding two series into one duplicate
series and failing the whole scrape target. Escaping is now
byte-oriented, which is injective and also avoids the per-rune decode
cost on a large value.
Every store-backed family's HELP text now states its aggregation
contract: with Redis configured, the value is the gateway-wide total
and identical on every replica, so summing across replicas overcounts
by the replica count and a cost alert fires early. Aggregate with
max() instead. Without Redis, the same family becomes genuinely
per-process and sum() becomes correct instead. The rejection counter
and the provider-healthy gauge get their own notes: the former is
always per-process regardless of Redis, the latter reflects each
replica's own independently-running discovery breaker.
Also replaces the AllowedCIDRs doc example (10.0.0.0/8) with a
cluster pod CIDR (10.42.0.0/16) and states plainly that a whole
RFC1918 range is never correct, since a SNAT-ing router or load
balancer makes external traffic arrive from inside it — reproduced
live against the target cluster.
Adds tests pinning three properties mutation-proofed against this
suite: every storeDown skip (deleting any of them now fails
TestMetrics_StoreDown_SkipsRatherThanFabricatesZero), the CIDR-check
running before auth.identify (TestMetrics_
AllowlistedRequest_NeverTouchesAuthFailureTracking), and
escapeLabelValue's injectivity under invalid UTF-8
(TestEscapeLabelValue_InvalidUTF8_Injective). Also covers the new
rejection-counter pruning end to end through a real file-sourced
reload.
Two correctness fixes from adversarial verification.
providerUsage returned every counter at its zero value on a
failed-closed store read, with no signal distinguishing that from a
real zero. metrics.go rendered the zero as a hard value. A single
Redis blip therefore read as a counter reset, and the recovery scrape
counted the whole prior total as a fresh increase, painting a phantom
multi-thousand-request spike from one transient error. Add storeDown
to providerCounters and set it on the failed-closed path, mirroring
scopeUsage's existing contract.
limiter.rejections grew without bound: nothing ever removed a scope
whose user was renamed or deleted from a hot-reloaded users file, so a
long-running process kept exporting a series for every name ever seen.
Bound the map with the same current/previous generation-rotation
authFailureTracker already uses, and evict a user's entry when
authStore.maybeReload performs a real reload. maybeReload now returns
whether it actually reloaded, so ServeHTTP only runs the eviction walk
on that rare event, never on every request.
Also corrects a stale comment: the rejection counter's store-down
branch fires on every request during a full outage, not rarely, as an
earlier comment claimed.
Cover an undefended half of runMeteredCall's own cacheable guard
(routes_unified.go): "!streaming" was asserted nowhere end to end.
Existing streaming tests only checked chunk delivery and mid-stream
accounting, never the cache header or store state.
Add a test that drives a real streaming chat-completion request
through a Gateway with caching enabled and proves no X-Llmgw-Cache
header appears, and that the cache holds no entry under the key a
non-streaming request for the same body would use.
Confirmed to fail against a real mutation (dropping "!streaming" from
the cacheable expression) before being kept; the mutation and its
revert are recorded in the test's own doc comment.
Cover failPolicyIncrBy (0% covered), and add direct tests for
storeIncrBy and storeGet against a real store, not only the nil-store
fallback path the existing suite exercised.
Each direct test proves four branches: a nil store always uses the
in-process fallback, a configured store's success returns the store's
own value rather than the fallback's, a store error records the
failure and falls through to the fail-open/fail-closed policy, and an
open store-down latch skips the network call entirely until it
expires.
Add a direct test for logSpawnDrop (0% covered), proving it logs once
per storeErrorLogEvery like its sibling logStoreError, sharing the
same rate-limit gate by design.
Every test was confirmed to fail against a real mutation of the
target function before being kept; each mutation and its revert are
recorded in the test's own doc comment.
Cover four zero-coverage functions on the /v1/messages route Claude
Code drives on nearly every call: openAIToolsFromAnthropic,
openAIToolChoiceFromAnthropic, responseTranslationError.Error, and
writeAnthropicProviderUpstreamError.
Add table-driven tests for every tool_choice form (auto, any,
tool-by-name, unrecognized, absent, non-map, nil), a multi-tool
mapping test that checks field order, description omission, and
malformed-entry skipping, a full request-to-response round trip
through a forced tool call, and a test proving no-tools/no-tool-choice
omits both keys rather than sending an empty array.
Add direct tests for the Anthropic-shaped upstream error envelope
(status passthrough, error.code, decoded error.upstream) and for the
translation-failure error prefix.
Every test was confirmed to fail against a real mutation of the
target function before being kept; each mutation and its revert are
recorded in the test's own doc comment.
Add failover.go with the full candidate pipeline. resolveWithCandidates
resolves a request exactly like resolve does, then adds every other
provider sharing the identical bare model id. orderedFailoverCandidates
applies a hard skip for request-path-unhealthy providers, deprioritizes
discovery-unhealthy providers without dropping them, fails open when
every candidate reads unhealthy, and caps the list at maxAttempts.
Add requestHealthTracker, a separate per-pod request-path health signal
fed by the same isTransient/isDeadlineExceeded classification
recordProviderAttempt already uses. It never widens the existing
discovery circuit breaker, per that breaker's own documented scope.
Rewrite runMeteredCall (routes_unified.go) to loop over candidates
instead of resolving once. Each attempt rebinds the attempt recorder to
its own provider, recomputes the cache key before the response is
cached, and re-injects the alias echo key an adapter may have deleted on
a prior failed attempt. Failover never runs once any byte has reached
the client, since statusTrackingWriter already tracks that state.
A failure falls through on everything except HTTP 400, matching the
brief exactly. A 404 failover logs loudly, naming both providers and the
model, since it usually signals a real configuration mistake.
Add FailoverConfig (Config.Failover): an Enabled pointer defaulting to
true, and a MaxAttempts bound between 1 and 10, defaulting to 3. A
single-provider deployment, or one with no overlapping bare model ids,
behaves exactly as before regardless of this setting.
Add a yaegi-check probe (tools/yaegi-check/main.go) driving two
providers under the real interpreter, one failing and one serving,
proving the candidate loop runs correctly interpreted.
Update README.md with a Failover section and correct the Retry
section's stale claim that no cross-provider failover exists.
Media routes (images, audio speech, audio transcriptions) do not get
failover in this change. Each has its own request-shape handling that
needs its own scoped follow-up.
Compiled tests have repeatedly passed on this codebase while the
interpreted shape failed, so the metrics feature needs its own probe
in this harness, not just go test coverage.
Enable metrics in the harness config, with modelLabel on so the
opt-in provider-model breakdown runs interpreted too. Add
exerciseMetricsRoute, driving four real requests: unauthenticated
from outside the allowed CIDR block returns 401, a non-admin key
returns 403, the admin key returns 200 with the expected TYPE lines
and live provider and model data in the body, and a keyless request
from inside the allowed CIDR block returns 200.
Run the new probe last, after the breaker probe settles, since GET
/metrics triggers the same maybeRefresh call every route does and
the breaker probe's own hit counting is timing-sensitive.
Serve a hand-written Prometheus text-exposition document at a
configurable path, defaulting to /metrics. The plugin is stdlib-only
under Yaegi, so this cannot use a client library.
Add MetricsConfig: Enabled gates the route, Path overrides it,
AllowedCIDRs lets an unauthenticated caller scrape from a trusted
source address, and ModelLabel opts into a per-(provider,model)
breakdown that defaults off to avoid a series-count explosion.
Reuse the existing admin bearer-token auth path instead of adding a
second credential check. Reuse the batched, chunked reads GET
/admin/api/overview and GET /admin/api/usage already use, so a scrape
costs no extra store round trip.
Expose request, token, and cost counters per scope, provider attempt
and failure counters, a provider-health gauge from the discovery
circuit breaker, and a budget-consumed-ratio gauge per limited scope
for Prometheus alerting. Add a rate-limit-rejection counter in
limits.go: this is the one number with no existing accounting to read
back, so checkAndCount now increments a small in-process,
per-process-lifetime counter on every violation.
Escape every label value for backslash, double quote, and newline. An
unescaped quote in a label value, such as a discovered model id, makes
the whole scrape unparseable, and Prometheus reports an unparseable
scrape as the target being down rather than as one bad line.
Cover the auth gate matrix, exposition structure (TYPE per family,
counters ending _total, no duplicate series), label escaping
round-trips, the model-label opt-in, and counters reflecting real
seeded usage rather than zeros.
Replace the alias-echo rewrite on the Anthropic passthrough branch
with a byte-preserving field replacement. The prior version decoded
the response into a Go map and re-marshaled it. This silently
corrupted a JSON integer beyond float64's exact range. It also
rewrote 1.0 to 1, HTML-escaped angle brackets and ampersands, and
re-sorted every key. A tool_use block's "input" is arbitrary
model-generated JSON. A long numeric id inside tool arguments could
be silently corrupted on a route documented as passthrough.
rewriteModelField now walks the response with a JSON decoder and
copies every field but "model" as raw bytes.
Add a test with a 20-digit integer, a 1.0 float, and a literal "<"
character inside tool_use input. It asserts the response is
byte-identical to the source apart from the model field.
Add a negative test for the anthropic-beta header allowlist. It
asserts Authorization and Cookie never reach the upstream. It also
asserts the upstream sees exactly one x-api-key value: the gateway's
own key, never the client's. A single Get() call could miss a second,
leaked value, since Set() and Add() interact in a way a naive check
would not catch. The test checks the Values() length explicitly.
Add a test case for the native passthrough route's prompt-cache
billing. It fails if cache_creation_input_tokens or
cache_read_input_tokens drop out of the billed prompt count. This
closes a production billing change that previously carried no
coverage at all.
Decouple response delivery from usage extraction on the passthrough
branch. A response body read failure, or a malformed usage field, no
longer both discard the response and misreport the failure as an
upstream connection error. A read failure still returns an error, now
correctly classified as a translation failure. A malformed usage
field no longer blocks the response at all: the client still gets
it, and the existing zero-usage estimate takes over for accounting.
Return the adapter's own usage value on a chatCompletion error in the
translated path, instead of discarding it. This has no effect while
streaming stays rejected up front. It prevents the same critical bug
from resurfacing once streaming support lands.
Normalize tool_result content to a plain string before applying the
error prefix. The prior version only prefixed a Go string. Anthropic's
array content form, which Claude Code sends, lost the is_error signal
entirely. Absent content now becomes an empty string instead of the
JSON null OpenAI rejects.
Treat "stream": null the same as an absent key. The prior fix for a
non-boolean stream value also rejected null. An SDK that serializes an
unset optional field as null must still get an ordinary non-streaming
response.
Drop a yaegi-check assertion that could not fail. The fixture
configures no cache, so the header it checked was never set regardless
of what the code under test did. A mutation pass confirmed this: it
deleted the line the assertion was meant to guard, and make
yaegi-check still reported OK.
Document that this route now intercepts POST /v1/messages
unconditionally, even under passthroughUnknown, where it previously
fell through to the next handler. Add the note to both the new README
section and Known limitations. Correct the passthrough table's claim
about response bytes to describe the actual guarantee.
ProvidersView.vue's accordion detail row hardcoded text-destructive red
for any non-closed health state, while the trigger row's Badge
deliberately used grey (secondary) for half-open and red (destructive)
only for open. Add healthDetailClass so the detail row's color always
matches the badge's own severity, instead of overstating a half-open
probe as an error.
Add a describe block for formatUntil to format.spec.ts, covering the
unset sentinel, undefined, a future timestamp, and a past one. It had
no test coverage since being added in the previous round.
The Provider health section claimed a broken provider stops being
re-probed "every single interval forever", while its own third bullet
said the opposite: under stock config the interval remained the
binding constraint and nothing was actually suppressed. Rewrite the
opening paragraph and the bullet to state the real relationship
plainly: the backoff window only ever reduces re-probe frequency once
it exceeds discoveryInterval, and the shipped defaults are chosen so
that holds.
Update every remaining reference to the old 30m maxOpenDuration default
to the new 6h value, in the BreakerConfig reference table and the
Provider health section, and explain what a misconfigured relationship
between discoveryInterval and maxOpenDuration does.
Address the design finding and remaining defects from round 3 of
adversarial review.
Raise defaultBreakerMaxOpenDuration from 30m to 6h. Round 2 fixed the
breaker so it never retries more than plain interval throttling, but
left it cadence-neutral: with maxOpenDuration shorter than the 1h
default interval, the interval always dominated and backoff never
suppressed anything. Measured over 24h with stock config, admits
equaled the interval-only baseline exactly. At 6h, a permanently broken
provider now backs off 1h, 2h, 4h, 6h, 6h, roughly 5 attempts a day
instead of 24. The 24h cadence test now asserts admits are strictly
fewer than baseline, not merely no worse.
Correct the emitted openUntil to account for the interval floor.
Because the interval gate applies unconditionally, the real next probe
time is max(openUntil, lastRefresh+interval), not the raw backoff value
alone. On pure defaults a fresh trip set the raw value to +1m while the
real next probe was at +1h, a 59 minute skew the dashboard rendered as
a countdown that reached zero and then silently vanished. snapshot now
emits the corrected value while open; closed and half-open are
unaffected.
Revert a canceled half-open probe to open instead of leaving it at
half-open. A half-open breaker reports healthy by design, so a canceled
probe previously left a still-broken provider reading healthy until the
next attempt happened to land. Reverting costs nothing extra, since the
interval gate already governs when that next attempt is admitted either
way.
Rewrite the discovery-suppression claims in doc comments: the earlier
wording claimed re-probing stops "every single interval forever" under
all conditions, which the interval-floor fix from round 2 already made
false, and which contradicted this file's own surrounding explanation.
Both now state plainly that suppression only occurs once backoff
exceeds discoveryInterval.
Add a sentence to recordHealthLocked's doc comment stating that
context.DeadlineExceeded counts as a plain failure, matching
recordProviderAttempt's SHOULD-1 ruling, and a named test proving it.
Tests: two new snapshot tests pin the openUntil correction in both
directions. The cadence test's baseline comparison is now strict. A new
test proves the zero value truly disables the breaker rather than
tripping on the first failure. A new test proves a canceled context
never gets misclassified as a failure, completing the bidirectional
check the existing success-direction test already had. The concurrent
test now asserts backoff stays within its ceiling and health stays a
valid state on every iteration, rather than only checking for panics
and data races.
lukaszraczylo