StartDeployment read the whole config DB twice with no transaction — DraftSnapshotFactory for
the validator, then ConfigComposer for the artifact, plus clusters/nodes and Script.SourceCode
again in between. An AdminUI save landing between the two shipped an artifact the DraftValidator
never saw.
- DraftSnapshot carries ServerClusters, ClusterNodes and ApiKeys; DraftSnapshotFactory reads
every table inside one SNAPSHOT transaction on a relational provider (no-op on InMemory or
under an ambient transaction).
- ConfigComposer.Compose(DraftSnapshot) is pure over the snapshot (ordinal-sorted keys);
SnapshotAndFlattenAsync(db) delegates to it, byte-identical.
- AdminOperationsActor validates topology, estimates compile cost and composes the artifact
from the one snapshot it holds.
- Migration EnableSnapshotIsolation: ALTER DATABASE CURRENT SET ALLOW_SNAPSHOT_ISOLATION ON
(suppressTransaction; no model change).
Tests: the SQL Server snapshot read ignores a row committed mid-read (positive control: a later
read sees it); an edit injected between the Equipment and Tags reads is absent from the shipped
artifact and rejected by the next deploy; Compose(snapshot) == SnapshotAndFlattenAsync(db).
Refs #733
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
WP1 wrote these against its interim VirtualTag-only collision rule; WP4a replaced it
with the broader UnsEffectiveNameCollision rule. Neither test-sweep scope covered these
two Configuration.Tests files, so the assertions went stale. Configuration.Tests 107/107.
Filter ExternalIdReservations to WHERE ReleasedAt IS NULL so
DraftSnapshot.ActiveReservations matches its documented semantics and
ValidateReservationPreflight cannot emit spurious BadDuplicateExternalIdentifier
errors from already-released rows. Adds a focused unit test seeding one active
and one released reservation and asserting only the active row is returned.
Joseph Doherty