- BucketPlan: reverse processed reads anchored at the later time for every
aggregate: window (end, start], partial interval earliest, results stamped
with the later edge, latest first (SDK CreateSlice/GetTimestamp/backward
GetValues). SqlServer adds @bucketAdjustTicks + flips the window predicate;
QuestDB binds BucketBaseUnixTicks. IndexOf is the C# statement of the math.
- Partial bit on the interval the tag's data starts inside (SDK m_startOfData),
every aggregate but Average; per-sample reads fetch the earliest sample.
- Node manager: non-default client AggregateConfiguration =>
BadAggregateConfigurationRejected per node (ServerAggregateConfiguration,
pinned to the SDK AggregateManager defaults).
- GatewayTagProvisioner sends IntegralDivisor = 1.
- SDK parity oracle (Opc.Ua.Server calculators) in unit + both backends'
conformance suites, forward and reverse; remaining divergences documented.
- docs/Historian.md + CLAUDE.md release note (client-visible).
- EndpointSelector rewrites host AND port to the user-supplied URL (same scheme only)
- AggregateType/mapper/CLI/UI gain TimeAverage, TimeAverage2, Total, Total2, Interpolative
- HistoryReadCommand turns ServiceResultException into a one-line CommandException
- NodeManagerHistoryReadTests non-historized case sets IsReadModified=false
Every HistoryUpdate a SQL backend applies now leaves a modification trail
(prior value, principal, Part 11 update type, modification time), and
HistoryReadRaw with IsReadModified=true serves it as HistoryModifiedData.
- Core: HistoryUpdateContext threaded into all three IHistorianDataUpdater
methods; IHistorianDataSource.ReadModifiedAsync (default NotSupported =>
BadHistoryOperationUnsupported on Gateway/Null); HistoryModified* contracts.
- SqlServer: schema v2 (002_sample_modified.sql, RequiredVersion=2, docs copy);
trail written by OUTPUT ... INTO on the same MERGE/DELETE statement, so a
failed update leaves no audit row; retention purges SampleModified per tag on
the source-time cutoff; ReadModifiedAsync keyed on (SourceTimeUtc, ModifiedId).
- QuestDB: append-only {prefix}sample_modified (TTL like samples), trail row
written BEFORE the change (orphan-on-crash, never an untracked change);
existence reads now carry the prior value; ReadModifiedAsync.
- Node manager: modified reads dispatch + page via the #669 continuation store
(HistoryContinuationState gains HistoryCursorKind + LastModifiedId), gated by
the existing HistoryRead decision; session principal / key id passed to the
updater. IsDeleteModified stays unsupported.
- Client.CLI: historyread --modified.
- Tests: node-manager dispatch/paging/cursor binding/principal threading,
over-the-wire HistoryModifiedData, shared ModifiedValueConformance on both
backends, SqlServer atomicity (forced trail failure => no change) + v1->v2
upgrade + retention trail purge.
- Docs: Historian.md (Modified-value history section, schema v2 upgrade note),
security.md, Client.CLI.md, CLAUDE.md.
M1: the time-weighted family (incl. Total, formerly a pushed-down SUM) streams
raw window rows into the C# evaluator. New shared knob
ServerHistorian:MaxTimeWeightedRawRows (default 1,000,000; <=0 unbounded with a
Validate warning) flows through HistorianBackendRegistry into both providers.
The window query is capped at cap+1 (SQL Server TOP (@maxRows), QuestDB LIMIT $4);
one row past the cap throws the new Core.Abstractions
HistoryReadLimitExceededException, which the node manager maps to
BadTooManyOperations for that node. Not counted as a backend health failure;
bound rows are not counted; per-sample aggregates are not capped.
M2: reverse Interpolative is anchored at the later time (Part 13): points at
End - i*interval, emitted latest first. 10:00->09:00 @1h yields 10:00.
L1: Partial bit (0x4, = Opc.Ua.AggregateBits.Partial) on non-Bad results of a
truncated last interval (time-weighted family; per-sample family is a follow-up).
L2/L3: aligned with the SDK AggregateCalculator.GetTimeBasedStatusCode
(decompiled from Opc.Ua.Server 1.5.378.106): TreatUncertainAsBad=false counts
Uncertain time (Uncertain samples, held-into-outage, extrapolation) as Good
time; data but no non-Bad time => generic Bad (0x80000000); BadNoData only
when there is no data at all. Consequence: a live tag's latest interval reads
Good (documented).
L5: release note no longer claims Total matches the Gateway Integral exactly
(AVEVA's divisor is unverified); it notes Total is now evaluated in C# and
subject to the cap.
Tests: unit (reverse Interpolative x3, Partial, Bad vs BadNoData incl. an
open-ended outage, cap helpers, SDK bit oracles); conformance (reverse
Interpolative, raw-row cap at/over/0, bounds not counted, health unaffected);
node manager BadTooManyOperations; options default + warning. Each new
behaviour falsified by mutation (aggregator x9, data-source cap checks on
both backends against the real DBs, node-manager catch).
New AggregateFamily.TimeWeighted serving TimeAverage, TimeAverage2, Total,
Total2 and Interpolative, evaluated by the shared Sql.Common
TimeWeightedAggregator for both SQL backends (identical results by
construction). HistoryAggregateType gains TimeAverage2 + Total2 (appended);
OtOpcUaNodeManager.MapAggregate maps their NodeIds. Gateway's mapper already
refuses unknown defined members => BadAggregateNotSupported per node.
Semantics (server defaults, client AggregateConfiguration ignored):
TreatUncertainAsBad=false, PercentDataBad=PercentDataGood=100,
UseSlopedExtrapolation=false. Sloped for Double/Int64, stepped for Boolean;
a usable sample followed by a Bad one is held up to the outage (AtTime rule);
stepped Uncertain extrapolation past the last sample. TimeAverage/Total use
interpolated bounding (bridge outages); TimeAverage2/Total2 exclude Bad time.
Bounding values: latest usable + latest any before start, first any + first
usable at/after end (four TOP 1 / LIMIT 1 seeks).
CLIENT-VISIBLE: Total on SqlServer/QuestDb was SUM of samples; it is now the
time-weighted integral (TimeAverage x interval seconds), matching Gateway's
Integral. Release note in docs/Historian.md.
Trade-off (deviation from the preferred hybrid pushdown, allowed by the
design): the time-weighted family is NOT pushed down. Each read streams the
window's rows plus the four bounds (SQL Server: one five-result-set batch;
QuestDB: bounds UNION ALL + window select) into the C# evaluator. Network is
O(samples in window), memory O(buckets). Writing the per-segment
interpolation/edge splitting twice in two SQL dialects and keeping them
bit-identical was judged the bigger risk; this also makes the QuestDB
lag/lead spike moot.
Tests: 35 hand-computed TimeWeightedAggregator unit cases (each of 10
implementation mutations goes red); served-aggregate pin 13 -> 17;
conformance sparse fixture (intervals wider and narrower than sample gaps)
+ an outage straddling both window edges (each of the four SQL seeks
disabled in turn goes red); node-manager NodeId mapping test.
The tests probe a free port (bind 0, release) and start the SDK server later; under a
highly parallel run another test can take the port in between and the SDK fails with
'Failed to establish tcp listener sockets for Ipv4 and IPv6.'. OpcUaHostStart.StartAsync
builds a fresh host + server on a fresh port per attempt (up to 5) when the failure is a
bind failure; all 45 start sites in OpcUaServer.Tests, OpcUaServer.IntegrationTests and
Runtime.Tests use it. Per-attempt GUID ApplicationUris are hoisted out of the host factory
because a changed URI against a reused PKI store fails with 'Cannot access private key'.
Claude-Session: https://claude.ai/code/session_01Ef2ozxS7QPanGT8uoATbTe
H1 (HIGH): write-routing key now (AddressSpaceRealm, bareId), not bare-only.
A raw s=<RawPath> and a UNS s=<Area/Line/Equip/Eff> can collide as bare
strings; the bare-only key let a colliding raw+UNS pair route to the WRONG
driver ref (last-writer-wins). The realm the node manager resolves (RealmOf)
is now threaded through IOpcUaNodeWriteGateway.WriteAsync -> RouteNodeWrite ->
_driverRefByNodeId keyed by (realm, bareId). New regression test:
Colliding_raw_and_uns_bare_ids_route_to_their_own_driver_by_realm.
M1 (MEDIUM): discovered-node injection made coherently DORMANT. HandleDiscoveredNodes
hard-short-circuits (single enforcement point; _discoveredByDriver never
populates so the re-inject tail is inert too), with a clear log pointing at the
/raw browse-commit flow. New pin: Discovered_nodes_are_ignored_dormant_in_v3;
the 16+2 v2 injection scenarios re-pointed to an accurate skip reason
(DiscoveryInjectionDormantV3).
M2 (MEDIUM): realm-qualified dual-node self-correction tests —
Failed_uns_write_reverts_uns_node_and_leaves_raw_node_untouched +
Raw_realm_revert_reverts_raw_node_only (the second fails if the realm is dropped).
L1: removed the = AddressSpaceRealm.Uns defaults from the consequential
node-manager mutation methods (WriteValue/WriteAlarmCondition/MaterialiseAlarmCondition/
EnsureFolder/EnsureVariable/UpdateFolderDisplayName/UpdateTagAttributes/
RaiseNodesAddedModelChange/Remove*/RevertOptimisticWriteIfNeeded) + the
AttributeValueUpdate/AlarmStateUpdate records, so the compiler forces explicit
realm; read-only accessors + internal builders retain their defaults.
L3: fixed the stale VirtualTagHostActor class comment (V3NodeIds.Uns, not the
retired EquipmentNodeIds.Variable).
Also: DeploymentArtifactRawUnsParityTests — Raw/UNS node-set byte-parity
round-trip between AddressSpaceComposer.Compose and DeploymentArtifact.ParseComposition.
Claude-Session: https://claude.ai/code/session_01LVneM3eh1UtJxEisFXgmox
Fix A: add Raw_multi_node_per_node_error_isolation test — two historized variables
(eqA/good→A.PV, eqB/bad→B.PV) in one Raw batch; per-tagname fake throws for B.PV,
returns a sample for A.PV; asserts errors[0]=Good+sample, errors[1]=Bad,
HistoryData[1]=null (no cross-slot leak), no exception escapes.
Fix B: collapse double ConcurrentDictionary lookup in ServeNode — TryGetHistorizedTagname
now captures `out var tagname` on the guard; the resolved tagname is threaded into the
read callback as a second parameter (Func<IHistorianDataSource, string, Task<HistorianRead>>),
removing the redundant ResolveTagname helper (deleted) and the tiny race window between
the check and the second lookup. All three call-sites (Raw/Processed/AtTime) updated.
Fix C: rewrite the IsReadModified comment at NodeManagerHistoryReadTests.cs:102 — the
SDK's ReadRawModifiedDetails.Initialize() sets m_isReadModified=true (generated ctor body
in Opc.Ua.DataTypes.cs), so the default IS true; the test must explicitly clear it to
false for a plain raw read. Previous comment said the same thing but imprecisely; now
cites the SDK mechanism (Initialize() call in the public ctor).
Joseph Doherty