test(resilience): fill the gaps in the resilience and failure-mode tests - #1333
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The old test stalled a request body against a backend that never read it, so the backend answered right away and the test passed no matter what the proxy did. It now uses an echo backend, so the body matters, and checks that the proxy cuts the upload off with its 400 inside the timeout window. Renamed to match what it actually sends. Signed-off-by: Shane Utt <shaneutt@linux.com>
The suite only drove the breaker open, half-open, and back open again. Now it also checks the other half: a good probe closes the circuit and resets the failure streak, and while that probe is still in flight every other request gets the breaker's 503 without touching the backend. The backend starts out healthy because the harness's readiness probe goes through the breaker and would otherwise count as the first failure. Signed-off-by: Shane Utt <shaneutt@linux.com>
Every misbehaving backend in the suite gave up before finishing its header block, so nothing checked what happens once a response is already streaming. Three new cases do: a backend that sends more than its Content-Length (the client gets exactly the declared bytes and the connection never goes back into the pool), one that resets the connection partway through the body, and one that stalls mid-body under a read timeout. In the last two the client has to see a short body and a closed connection, and the proxy keeps serving afterwards. The reset case needs SO_LINGER 0, which tokio already exposes, so the suite now asks for tokio's net feature directly instead of getting it through the test harness. Signed-off-by: Shane Utt <shaneutt@linux.com>
A backend hostname that doesn't resolve now has an end-to-end test: the request fails fast, the negative cache answers the retry just as fast, and other clusters keep working. It comes back as a 500, though, while the iterative request router turns the same failure into a 502, so the test that pins 502 is checked in but ignored until that's settled. On the TLS side, the wrong-certificate case was already covered. These add a backend that never answers the handshake (504 once total_connection_timeout_ms runs out), a plaintext backend behind a tls: cluster (502), and an expired certificate (502, next to an in-date control). TestCertificates grows a generate_expired helper for that last one. Signed-off-by: Shane Utt <shaneutt@linux.com>
A backend that accepts a 16 MiB upload and never reads it now gets the request a 504 that names the write timeout. The write timeout doesn't end the request on its own: the proxy stops sending but still waits for a response in case the upstream already answered, so the test pairs it with a read timeout. Without the write timeout the request just hangs, because a blocked body write keeps the read timeout from ever firing. The concurrency suite also gets a mixed burst: 32 workers sending GET, DELETE, POST, and PUT across two routes, with bodies anywhere from empty to 256 KiB. Every echoed body is checked byte for byte so a crossed response would show, and the proxy has to answer normally afterwards. Signed-off-by: Shane Utt <shaneutt@linux.com>
Raw garbage and a cut-off header block from the upstream already had 502 tests, but nothing covered a status line that's almost right (no code, a non-numeric or four-digit code, no space after the version) or a header line with no colon. The response parser only relaxes spaces after a field name and obs-fold, so all of those have to come back as 502. A well-formed line through the same backend is the control in each test. Signed-off-by: Shane Utt <shaneutt@linux.com>
The cluster timeout docs promised a 502, but read, write, and total connection timeouts all come back to an HTTP client as 504 (the new resilience tests pin each one). The read timeout doc also pointed at total_connection_timeout_ms for bounding the whole exchange, which only covers connection setup, so that line is gone. It now says what happens once a response is already streaming, and the write timeout doc explains that the proxy still waits for a response after a body write times out, so it needs a read timeout next to it. Signed-off-by: Shane Utt <shaneutt@linux.com>
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Included review availability: This review used your included allowance. Your plan provides up to 10 included reviews per hour; 8 remain after this review. 📝 WalkthroughWalkthroughThis pull request updates cluster timeout documentation and expands HTTP conformance and resilience tests. The tests cover malformed upstream responses, backend failures, circuit-breaker recovery, DNS and TLS failures, and concurrent mixed requests. ChangesHTTP conformance and resilience coverage
Priority: ➖ Normal Estimated code review effort: 3 (Moderate) | ~25 minutes Change: Other Suggested reviewers: Merge Risk: ⚪ Minimal · up to This change expands resilience coverage and clarifies timeout documentation without establishing a production behavior regression. The unresolved DNS status-code expectation is ignored, so no specific production mismatch remains to block merging. 🚥 Pre-merge checks | ✅ 4 | ❌ 1❌ Failed checks (1 warning)
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Full details: Linked Issues checkExplanation PR Resolution Add or establish reviewable coverage for connection-pool exhaustion, DNS resolution timeout, rate-limit refill at the window boundary, and memory stability during large streamed responses. Resolve the DNS error mapping and activate the required status assertion when the expected behavior is defined. Autopilot is paused · Paused
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Inline comments:
Review comments at @tests/conformance/tests/suite/rfcs/test_utils.rs:
- Around line 142-144: Update the doc comment on start_status_line_backend to
explain why tests need caller-supplied raw status-line bytes, rather than merely
describing its behavior. Remove the redundant comment on
handle_status_line_connection and retain a doc comment on the test helper.
Review comments at @tests/resilience/tests/suite/backend_failure.rs:
- Line 404: Remove the inline size comment from the chunk declaration in the
backend failure test; keep the 65_536 value and test behavior unchanged.
Review comments at @tests/resilience/tests/suite/circuit_breaker_resilience.rs:
- Around line 289-295: Update start_switchable_backend to use the shared guarded
backend harness instead of creating an ad hoc listener and detached accept
thread. Reuse or expose the harness’s cloneable per-connection handler to
capture Arc<BackendSwitches> and select the response per request; return or
retain a BackendGuard so dropping the backend shuts down its listener.
Review comments at @tests/resilience/tests/suite/dns_failure.rs:
- Line 29: Set a request deadline shorter than the five-second assertion window
for the http_get call in the DNS failure test, so a stalled resolver cannot
consume the entire window; keep the elapsed-time assertion unchanged.
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Signed-off-by: Shane Utt <shaneutt@linux.com>
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What does this PR do?
Adds the resilience tests the gap checklist was still missing: circuit breaker recovery, upstream resets, overreads and stalled bodies, upload write timeouts, DNS failures, broken upstream TLS handshakes, malformed upstream responses, and a mixed concurrent burst. Test code only, plus one doc fix the tests turned up (the cluster timeout docs promised 502 where the proxy answers 504).
write_timeout_mson its own doesn't end a stalled upload, only alongsideread_timeout_ms; the docs now say so.max_connectionsisn't enforced yet), rate-limit refill timing, and a memory ceiling, each needing a product decision first.Which issue(s) does this relate to?
Fixes #636
Checklist
git commit -s)make lint && make test && make test-integrationpasses locallyDoes this introduce a breaking change?
No.
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