The live-DNS retry and concurrency limit is only for tests, but nothing
stopped program code from importing it and compiling it into the
binary. Its directory name now ends in test, and its import path is on
the test-support deny list in .golangci.yml, so make lint fails when
program code imports it. Every import and mention is updated to the new
name.
Model: opus-5-5
The watcher tests used a stand-in resolver and the resolver timeout test
a stand-in DNS client, against the rule that DNS is never mocked.
Watcher tests that look something up in DNS now run the real resolver
against live servers, each attempt on a new watcher. A DNS change is
tested by saving values live DNS never returns (names under .invalid,
192.0.2.1) in the state a check starts from, or by marking a real
nameserver failed. The timeout test queries 192.0.2.1, where nothing
answers. The live-DNS retry and concurrency limit moved from the
resolver tests to internal/livedns, so both packages share them.
NewFromLoggerWithClient had no other use and is gone. TESTING.md now
states the README's rule.
Model: opus-5-5
Rework of the unit at #93
(commit 9cb2c2b), against the review at
#136 (comment).
Review of 9cb2c2b found the quorum assertions could not fail on a
class of wrong answer. Each test banned exactly one bad status —
_AllReturnOK banned only nxdomain, _NXDomainFromAllNS banned only ok
— so resolver.StatusNoData passed both. nodata is a wrong answer, not
silence, and answeredCount counted it as answered, so it did not even
trigger a retry; with a quorum of 3 of 4 a single wrong nameserver
slid through undetected. That is assertion-loosening beyond what the
quorum change requires.
Tolerance is now a closed allowlist rather than a blocklist of one
status. unsanctionedStatuses() reports every per-nameserver result
whose status the caller did not explicitly sanction: ok/timeout/error
for the all-OK test, nxdomain/timeout/error for the NXDOMAIN test.
Silence (timeout, error) is the only thing quorum exists to tolerate;
any other status, including one added to the resolver later, fails by
name. answeredCount is likewise an allowlist of ok/nxdomain/nodata, so
an unknown status counts as silence and can only cause a retry and
then a loud failure, never a quiet pass.
Two harness tests cover the regression directly: three OK plus one
nodata (quorum satisfied, no nxdomain present — the input that used
to pass) is now reported as unsanctioned, and an unknown status is
neither counted as answered nor tolerated.
Verified by re-running the reviewer's probe: queryEachNS patched to
force one of google.com's four nameservers to return StatusNoData
turns both tests red, naming the offending nameserver and status —
--- FAIL: TestQueryAllNameservers_AllReturnOK (1.12s)
Should be empty, but was [ns1.google.com.=nodata]
every nameserver must answer OK or not answer at all:
ns1.google.com.=nodata ns2.google.com.=ok ns3.google.com.=ok
ns4.google.com.=ok
--- FAIL: TestQueryAllNameservers_NXDomainFromAllNS (1.34s)
Should be empty, but was [ns1.google.com.=nodata]
every nameserver must report NXDOMAIN or not answer at all:
ns1.google.com.=nodata ns2.google.com.=nxdomain
ns3.google.com.=nxdomain ns4.google.com.=nxdomain
— and green with the probe reverted. Also fixes the review's nit: the
per-attempt deadline assertion had no lower bound, so it passed for a
deadline far shorter than intended.
No production code changed; DNS is still never mocked.
The resolver's live-DNS tests failed nondeterministically, a different
subset each run. Three structural causes, all test-side:
- Burst fan-out. Every test in the package is parallel and the build
hosts have many cores, so all ~35 iterative resolutions started at
the same instant and, because queryServers walks rootServerList() in
fixed order, hit the same root server within milliseconds. Root
servers rate-limit that.
- No retry anywhere. One dropped UDP packet in a delegation chain
failed a test outright.
- Unanimity assertions. TestQueryAllNameservers_AllReturnOK and
_NXDomainFromAllNS required every one of a domain's nameservers to
answer, with no tolerance for one being slow.
New internal/resolver/livedns_test.go addresses each: a package-wide
gate bounds how many live resolutions are in flight at once, every
live operation gets three attempts with exponential backoff and its
own deadline, and multi-nameserver assertions now need a strict
majority rather than unanimity. The retry predicate is deliberately
transport-level -- "did a nameserver answer at all" -- never the
assertion under test, so a resolver that answers incorrectly still
fails on the first attempt. A nameserver that stays silent is
tolerated; one that answers wrongly is not.
livedns_harness_test.go tests that machinery directly: quorum
arithmetic, status counting, the gate's concurrency bound, per-attempt
deadlines, and recovery from a transient failure. It touches no DNS.
Nothing is mocked, faked, stubbed, recorded, skipped or build-tagged,
and production resolver behaviour is unchanged.
Test caps move to the new org-wide values ruled at prompts issue 41:
60s hard cap, 20s target, 90s -timeout backstop. REPO_POLICIES.md is
re-vendored byte-identical from sneak/prompts rather than hand-edited,
which also picks up the golangci-lint paragraph this copy had drifted
behind on. TESTING.md's stale 30-second target follows to 60.
#93
sneak
clawbot