ConfigComposer gzips the serialised snapshot (CompressionLevel.Fastest)
immediately after SerializeToUtf8Bytes and BEFORE taking the SHA-256, so
the compressed bytes ARE the artifact everywhere: Deployment.ArtifactBlob,
the LocalDb cache chunks, the gRPC fetch stream, and the RevisionHash a
FetchAndCache node verifies against. The invariant the deploy path rests on
— RevisionHash == SHA-256(stored/wire bytes) — is preserved, which is what
leaves the fetcher, the cache and the serve path untouched: nothing between
the composer and DeploymentArtifact.Open ever looks inside the blob.
Read side: Open() sniffs the gzip magic 1F 8B (valid JSON can never start
with 0x1F, so no framing of our own is needed) and inflates through a size
guard — MaxDecompressedBytes, 512 MiB, internal + mutable so the guard can
be exercised without inflating half a gigabyte per test run. Pre-upgrade
uncompressed blobs take the identical path they always did.
Every decompression failure — corrupt stream, truncated stream, over-limit
inflation — is reported as JsonException, the same exception family the
malformed-JSON path already owns. So the lenient static wrappers still
degrade to empty results and the apply paths still fail the apply and keep
last-known-good (#485); no caller's decision changes because the reason the
bytes are unusable changed.
gzip output is not guaranteed byte-stable across .NET releases. Harmless
here: the hash is computed FROM the emitted bytes at compose time and never
re-derived from the JSON, so the worst an implementation change costs is
one spurious "changed" revision after a runtime upgrade. Snapshot
determinism is unaffected — compression wraps the final bytes and reorders
nothing.
Tests: gzip/uncompressed parity through both the instance parses and the
statics, corrupt-gzip leniency through the wrappers, the size guard (with a
falsifiability control proving the same bytes inflate fine under the
production limit), and composer-side blob-starts-with-1F8B +
RevisionHash == SHA256(blob) with a control proving the hash is NOT over
the JSON.
Fix TESTS only (production already green) so the four in-scope test projects
compile + pass under the v3 dark address space:
- Core.Abstractions.Tests: drop AllowedNamespaceKinds/NamespaceKindCompatibility
from DriverTypeMetadata; rewrite EquipmentTagRefResolver tests to the single-func
RawPath-lookup contract (no parseRef/transient cache).
- Core.Tests: rewrite EquipmentNodeWalkerTests to EquipmentNamespaceContent(Areas,
Lines,Equipment,VirtualTags?,ScriptedAlarms?) — folders + VirtualTags +
ScriptedAlarms only; raw-tag variables dark (skipped Batch-4 placeholder). Drop
retired Equipment.DriverInstanceId.
- Runtime.Tests: rewrite golden corpus + TagConfigCorpusParityTests to the v3
RawPath/RawTagEntry round-trip (byte + TagConfigIntent parity; EquipmentTags dark).
Salvage VirtualTag + ScriptedAlarm artifact parity to the new Compose signature.
Retire the equipment-tag-materialization parity files (Array/Historize/Alias) and
the equipment-device-binding DeviceHost parity to documented skipped placeholders.
Skip 34 dark equipment-tag routing/value/alarm/write/discovery actor tests with a
shared DarkAddressSpaceReasons constant. Re-key cluster-scoped tests to v3 UNS
line->area attribution.
- ControlPlane.Tests: ConfigComposer round-trips re-keyed to RawFolder/Device (no
Namespaces); tag-config gate resolves driver via Device; deploy-gate collision test
re-keyed to UnsEffectiveNameCollision; drop retired BadCrossClusterNamespaceBinding
case.
The arch-review #10 sub-gap worried that per-instance ResilienceConfig never
reaches the runtime pipeline. The threading is in fact wired end-to-end (task #13):
ConfigComposer serialises the whole DriverInstance entity, so ResilienceConfig
rides the artifact into DriverInstanceSpec, which DriverHostActor layers onto the
driver's Polly pipeline. The only leg with no test was the real composer->artifact
serialization — the existing DeploymentArtifactTests hand-build the JSON.
Adds ResilienceConfig_survives_ConfigComposer_to_ParseDriverInstances_round_trip
(mirrors the DeviceHost round-trip guard): seeds a DriverInstance WITH a non-default
override + one WITHOUT, runs the real SnapshotAndFlattenAsync, and asserts
ParseDriverInstances recovers the override byte-for-byte (and null stays null).
Guards against a future projection / [JsonIgnore] silently reverting authored
resilience policy to tier defaults while hand-built artifact tests stay green.
ControlPlane.Tests ConfigComposerTests 6/6 green.
Adds <summary>, <param>, <typeparam>, and <inheritdoc/> tags to public
members surfaced by commentchecker — resolves 5,847 of 5,869 issues
(99.6%) across three /fixdocs passes.
Joseph Doherty