The SDK memoizes INodeManager3.ValidateEventRolePermissions per (item, event type,
SourceNode). #826 kept it fresh by reflecting into the private
MonitoredNode2.InvalidatePermissionCaches (plus a detach/re-attach fallback). Since #855
condition events never take that channel, and the search for #878 found nothing
production-raised that does except a condition's SDK method audits, which reach it only
with auditing on, SignAndEncrypt and a SecurityAdmin session (nothing grants that role).
Under enforcement the channel verdict is now a flat deny for items on our nodes, so no
cached verdict depends on a grant, and InvalidateFolderEventVerdicts, the reflection,
the fallback, its counter and the guard test are removed. Method audits still reach
Server-object items, decided per event.
Tests: FolderEventVerdictInvalidationTests -> FolderEventVerdictFreshnessTests; new
revoked-grant test (positive control: a still-granted session) and method-audit test
(SecurityAdmin mapped for the test; positive controls: Server-object item, flag off);
the plain-event test runs each mode on a fresh server. Mutation-checked.
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
A notifier folder read one event source, its NodeId identifier (a RawPath or an EquipmentId). AVEVA stores a
Galaxy object's A&E history under the object's tag_name (Source_Object), so AVEVA's own alarm and event
history reached no production folder. Its lower-case property keys were also missed, so every row read
Severity 1 with no ConditionName.
Sources. A folder's event history now reads its own source plus the Galaxy object of every native condition
that fires on it live: those parented under it and those WireAlarmNotifiers wired to it. Live and history use
the same membership. The object comes from the condition's Galaxy alarm reference, its raw tag's attributeRef,
up to the first '.':
- The composer reads it with the driver's own parser (GalaxyAttributeRef, shared with GalaxyDriver), only for
a GalaxyMxGateway tag with an alarm (RawTagPlan.NativeAlarmReference, part of plan equality).
- The applier binds it after materialising the condition (IOpcUaAddressSpaceSink.BindNativeAlarmHistory,
forwarded by the deferred sink). A rebuild or the condition's removal forgets it.
Each object is read with the #882 rule: its own events and <Object>.<Attribute> rows, never a prefix sibling.
Fan-out. historiangw's ReadEvents filter is a single predicate, so there is one request per source; the wire
contract is unchanged. EventSourceFanOut merges the reads as one source:
- order is (time, source position, arrival), reversed for a reverse read; ties are never re-sorted by EventId,
so the boundary skip stays stable;
- duplicates by EventId are dropped and the merge is cut to the cap;
- a truncated source bounds the page at the time it stopped.
Paging, continuation points (bound to the whole source set), the walked-back reverse read and the tie-cluster
over-fetch are unchanged. A folder with one source is read exactly as before.
ACL. Every source is read inside the folder's own HistoryRead, after AuthorizeHistoryRead (#826). A denied
folder reads nothing and fails closed.
Mapping (EventMapper, property names now case-insensitive):
- Severity: an AVEVA row's priority goes through GalaxyAlarmPriority, the table live Galaxy alarms use
(MxAccessSeverityMapper now delegates to it), so history matches live. Otherwise severity (OtOpcUa's own
rows, which AVEVA stores lower-cased), clamped. AVEVA's own 1-4 severity is ignored. The table ranks a
higher priority as more severe, which inverts AVEVA's convention: filed as #887.
- An AVEVA row whose source_conditionvariable names a native condition that fires on the folder takes that
condition's SourceNode and live ConditionName. Otherwise ConditionName is alarmname or the condition
variable's attribute.
- alarm_id/alarmid map to AlarmId.
Tests:
- GalaxyEquipmentEventHistoryWireTests (4, real SDK session, production Gateway backend, AVEVA-shaped fake
gateway): equipment EqA backed by objects Oven_007 + OvenDoor_07. Covers object and attribute events from
both objects, the prefix sibling excluded, cross-object and in-object ties, forward paging at 1-4 a page,
reverse whole and paged, SourceNode/ConditionName/Severity, the raw device folder, ACL deny with no backend
call plus a granted positive control, and a rebuild forgetting the bindings.
- EventSourceFanOutTests (8), EventMapper AVEVA cases (11), GalaxyAttributeRefTests (16), a composer test and
an applier ordering test.
- Mutation-checked, 17 mutants, all killed. Covered: parent-only membership, no scope, a case-sensitive
condition match, no condition rewrite, no truncation bound, EventId tie order, no sort, no cap, no stop at
the bound, unreversed source order, no dedupe, no '.' boundary, priority ignored, case-sensitive keys, no
applier bind, no deferred forward, and a composer that ignores the driver type. The forget-on-rematerialise
guard survives as belt-and-braces: the rebuild clear covers it.
- Live, read-only, no WinRM, vd03 HistorianGateway ea9f21c: equipment folder EQ-886-ZipsenLeft (objects
DevWinPlatform + Left_001). It read 0 events before and 92 now, equal to the unfiltered read's rows for both
objects. 1/7-event pages and reverse whole/5-event pages agree, and 73 rows resolve to their live condition.
diff_runs vs the #882 run: 221/226 identical. The 5 that differ are expected: DevWinPlatform Severity
1 -> 750/1000, and #881 capabilities.
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
ConfigurationBinder appends configured collection items to an existing list, so
the pre-filled [None, Sign, SignAndEncrypt] default made "drop None" a no-op:
every deployment that listed only the secure profiles still advertised an
unsigned/unencrypted None endpoint.
EnabledSecurityProfiles is now null by default; ResolveEnabledSecurityProfiles()
applies the unchanged three-profile default only when nothing is configured.
A set-but-empty list fails startup validation and BuildSecurityPolicies no
longer falls back to a None endpoint on empty input (it throws). Sweep of all
options classes found no other non-empty pre-filled collection default.
Tests: options binding (indexed, JSON, env forms, default, empty, bad name), a
booted-server wire test (no None endpoint, None connection refused with
BadSecurityPolicyRejected, secure connection works; default case is the control).
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
The SDK starts Server.ServiceLevel at 255 (full service), and OpcUaPublishActor publishes nothing
until the node's first redundancy snapshot arrives, so a restarting pair node advertised 255 for the
~10-13 s it took to join, out-ranking the real Primary (250) for any client that picks the highest
ServiceLevel.
OtOpcUaSdkServer now writes StartupServiceLevel = 0 in OnNodeManagerStartedAsync: after the SDK's
CreateServerObjectAsync wrote 255 and before the server goes Running, so no session can ever read
255. 0 is the design's existing Down / Detached tier (ServiceLevelCalculator returns 0 for a member
that is not Up/Joining, and a node with no snapshot has no role yet). It is below the SDK 2
session-headroom floor (200), so it stands through session churn before the #884 claim, and the
claim's bind replays any level already requested. Single-node deployments are unaffected beyond
the window: the first snapshot publishes 250 as before.
New Node_with_no_requested_level_advertises_the_startup_level_until_one_is_published: reads 0
before the bind, 0 after a bind with nothing to replay, then 250 once published. Without the
startup write it reads 255 on the first session (mutation-checked). docs/Redundancy.md updated for
#884 and #885.
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
SDK 2.0.1 recomputes Server.ServiceLevel from session headroom on every session create/close and
overwrites any value >= 200 unless a provider has claimed it through
IServerServiceLevelControl.ClaimServiceLevelControl. SdkServiceLevelPublisher never claimed it, so on
the docker-dev pair both nodes read 255 as soon as a client connected while their own metrics showed
250 (Primary) and 240 (Secondary); the Stale tier's 200 was lifted to 255 too. Levels below 200 (100,
0) were untouched, which is why the bootstrap 100 showed briefly.
The publisher now claims the value at construction and writes through the SDK's writer; a server
without the claim (test doubles) keeps the diagnostics-guarded write. New
Published_level_survives_later_sessions (250/240/200) fails without the claim (reads 255) and passes
with it.
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
Every Boolean under Server/ServerCapabilities/HistoryServerCapabilities read
false (the SDK default) even though data and event history were served, so a
spec-following client skipped HistoryRead entirely.
Each backend now declares what it serves through its own interface:
- IHistorianDataSource.ReadCapabilities (Data / Events / ServerTimestamps):
Gateway Data|Events; SqlServer + QuestDb add ServerTimestamps (they store
ServerTimeUtc, the Gateway stamps read time); Null declares None. A
reflection guard requires every production source to declare it itself.
- IHistorianDataUpdater.Capabilities (required member): SqlServer and QuestDb
declare Insert/Replace/Update/DeleteRaw/DeleteAtTime; the Gateway provider
has no updater.
The node manager writes the flags on every source/updater assignment
(AdvertisedHistoryCapabilities), and the same declarations drive dispatch:
an update the updater does not declare is BadHistoryOperationUnsupported
without reaching it, the HistoryWrite AccessLevel bit follows a non-empty
declaration, and event-history notifier promotion follows the Events flag.
Event and annotation update flags stay false (nothing dispatches them).
Tests: booted-server wire test per backend + Null + a SqlServer->Gateway
rewire pairing on one session; dispatch gating unit test; the #801 live
gate now asserts the Gateway flags (not run here).
Claude-Session: https://claude.ai/code/session_01GT67ACmpMR7b9LGRPLijMi
OpcUaApplicationHost left ServerConfiguration.MaxRegistrationInterval at the
SDK default (30000) with a null RegistrationEndpoint, so SDK 2.0.1's
StandardServer armed its registration timer against opc.tcp://localhost:4840,
which on an OtOpcUa node is the server itself (no LDS). It answered
BadServiceUnsupported and the SDK retried forever, visible since #874.
Registration is now opt-in: ApplyDiscoveryRegistration sets
MaxRegistrationInterval = 0 (the value that keeps StandardServer from arming
the timer) unless OpcUa:DiscoveryServerUrl is set, in which case the server
registers against that URL every OpcUa:DiscoveryRegistrationIntervalMs
(default 30000) over SignAndEncrypt/Basic256Sha256, like the SDK's own
default endpoint. The validator requires an absolute opc.tcp:// URL and a
positive interval when the URL is set. Documented in Configuration.md and
OpcUaServer.md.
Co-Authored-By: Claude <noreply@anthropic.com>
The host handed the SDK a provider-less telemetry context, so SDK-side
refusals — identity-token decryption (the SDK 2 RsaEncryptedSecret clock
window, #873), certificate validation, secure-channel faults — left no server
log line (found on windev during the #800 Windows validation). The hosted
service now creates one ServerSdkTelemetry context from its ILoggerFactory
(Warning and above, SDK categories, rate-limited 20/min per category) and
shares it between OtOpcUaSdkServer and the ApplicationInstance; released on
dispose. Test: an untrusted client's rejection reaches the captured log.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
Since #855 condition events are queued to folder event items under the node
manager Lock. At a full DiscardOldest queue the SDK's EventQueueHandler
dequeues the head of EventMonitoredItemQueue, a List.RemoveAt(0) shift of the
whole queue (~1 us/item at QueueSize 1000, ~10 us at 10000).
OtOpcUaSdkServer.CreateMonitoredItemQueueFactory now wraps the SDK factory in
RingEventQueueFactory: event queues are RingEventMonitoredItemQueue (O(1)
discard), data-change queues, durable requests and disposal go to the SDK
factory unchanged. A factory set through StandardServer.MonitoredItemQueueFactory
is used as-is.
The SDK queue is storage only (decompiled 2.0.1): DiscardOldest, overflow-event
positions and discarded/overflow counters live in EventQueueHandler, which is
unchanged. The ring reproduces QueueSize 0 initial + BadInternalError enqueue,
drop-oldest at Count == QueueSize, FIFO dequeue, SetQueueSize keep-newest /
keep-oldest, the newest-1000 duplicate window via IsEventRaisedFor, no-op
Dispose. RingEventMonitoredItemQueueParityTests drive both queues, and the SDK
EventQueueHandler over both factories, with the same random sequences.
FolderEventDeliveryPerfTests gains Ring_vs_sdk_event_queue (A/B in one process
via the internal OtOpcUaSdkServer.RingEventQueues switch).
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- The sweep threshold never rises above the 4096 cap (a threshold the count
could not reach stopped sweeping, and sharing, for good); at the cap a
sweep for dead shapes runs after every 256 refusals.
- The per-report "queued" mark is taken after the filter group resolves,
so a failure there leaves the item unmarked.
- The bucket key also carries TypeDefinitionId and IndexRange.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- The filter-group registry holds groups weakly (the filter->group table is
the only strong reference), sweeps dead entries amortised and counts only
live shapes against the 4096 cap; filters past the cap are counted on the
new meter otopcua.opcua.condition_events.filter_groups_unshared.
- A group validates its where clause too (restored, never-validated filters
evaluate like validated ones).
- Test: value-equal filters cost one projection per locale set per report.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- Filter-group buckets include the where clause's (value-based) hash, so
per-source filters sharing a select list are not all scanned under Lock.
- Locale keys are cached per session array.
- Tests: a notifier reached twice in one walk (Line above two wired
equipment) gets each event once on both paths (fails without the
per-report set); queued events re-projected by a modify are identical on
both paths; locale keys unambiguous and where clauses hash by value.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- A filter group owns a deep clone of its first filter, validated once and
evaluated under the group's lock: no item-owned filter is mutated or raced
(Validate mutates a select clause).
- The projection is computed in the SDK's order: where clause first, fields
only for an item that will queue.
- Unambiguous locale key; counter for filters given a private group past the
registry cap; DeliveryCache getter returns its own allocation.
- UseProjectedEventDelivery=false also asks the role and grant checks per
item, so the equivalence test compares against the pre-optimisation path.
- Equivalence test: same select list under three where clauses, a filter
modified mid-run, a session with other locales, an ungranted anonymous
Server-object item, per-rig counter; plus a small overflowing queue with
DiscardOldest true and false.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
Condition events delivered to many event items (folder and Server-object)
no longer pay the SDK's per-item QueueEvent(IFilterTarget) work under the
node-manager Lock: the role-permission verdict is shared per (session,
identity), the #826 grant check per identity per hop, and the where clause +
select-clause projection per (value-equal EventFilter, locales); each item
gets its own EventFieldList over the shared read-only fields. The SDK's
QueueEvent body is reproduced under the item's own lock (three private SDK
members, guard-tested); anything outside that shape falls back to the SDK.
The per-report duplicate check replaces the SDK's O(queue) scan.
ProjectedEventDeliveryWireTests compares both paths over the wire.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- RefreshDirectItemsWithCut keys its "decided off Lock" set per (item,
condition), so a condition one item's walk saw is still decided for another.
- The deferral warning no longer blames slow folder subscribers (no folder of
ours defers since #855).
- FolderEventFloodWireTests' removal test now asserts the folder item got
nothing and the Server object exactly the pre-stall event (it passed with
the post-stall liveness re-check deleted).
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- Both plain ConditionRefresh paths (Server object and folder) skip a
condition a deploy removed or replaced between the off-Lock walk and the
queueing (the SDK base did not either; only the cut path checked).
- A failure delivering at one notifier hop is logged and the walk continues
to the remaining hops; a failure deciding the Server-object items withholds
only them.
- Test: a condition removed during a plain refresh (folder + Server object).
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- QueueFrozenReplay's verdict refuses a condition a deploy removed or replaced
since the cut (Server-object and folder), so the cut path cannot replay a
ghost or judge a replaced scripted alarm on its old folder.
- DeliverToNotifierItems resolves the #826 decision's item-independent part
(live condition, notifier check, scopes) once per hop; only the grant and
SDK role checks stay per item.
- A deferred delivery's drain starts on the pool, never inline under Lock.
- Test: a condition removed between the cut and its replay (folder + Server
object).
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
- QueueFrozenReplay re-asks each item's verdict right before each entry's gate
hold (Server-object and folder cut paths): a grant revoked between the
pre-Lock verdicts and the replay no longer lets the replay through. A denied
entry is also removed from the cut's re-sent set.
- ReportEventWithoutBlocking logs and returns on a delivery that faulted
inline instead of booking it as a deferral episode (which ran the drain and
ClearStaleRefreshCuts under the event-report gate while Lock was held).
- OnConditionReportEvent isolates failures per Server-object item.
- Tests: revocation between cut and replay (folder + Server object), throwing
hop not booked as a deferral; production-overload sampling inside Lock.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
When the data starts inside an interval (no start bound) and its first value is
Uncertain, the frozen 1.5.378.182 AverageAggregateCalculator integrated the
uncovered span as a ramp from 0 and divided TimeAverage by the whole interval:
GetRegionsInValueSet (ignoreBadData, sloped) overwrites the BadNoData start
region's status with UncertainDataSubNormal in its one branch without a not-Bad
guard. Live AggregateFilter therefore disagreed with HistoryRead and Part 13
§5.4.3.6/§5.4.3.8 ("No Start Bound: Calculate Partial Interval"); QP: Total
188.96 vs 163.96, TimeAverage 9.448 vs 10.931. SDK 2.0.1 stock does the same.
Owner-approved 2026-11-11.
- New app-owned CoveredTimeAverageAggregateCalculator subclasses the baseline
and recomputes only TimeAverage/Total, restoring the Bad status of a region
that starts at a Bad point (only the start bound can). Only such an interval's
value changes; status, timestamps, type and bits are the baseline's. Stepped
and TreatUncertainAsBad=true never reached the defect. CompatibilityAggregate-
Factory routes exactly those two IDs; copied SDK files untouched.
- Golden test: 0 fixture vectors change (every data set has a usable value at
-10 s), asserted. New sweep over late-start variants of every data set (cut
+5 s / +25 s, first non-Bad sample Uncertain, all directions/stepping/configs/
incremental): 150 / 142 of 384 change, each pinned to a baseline-derived
oracle (untouched baseline's value with that sample Good, its status/bits on
the variant itself) - never our calculator. Plus a hand-computed case.
- Live-vs-HistoryRead parity (TimeWeightedAggregator) forward + reverse, no
masks, with discrimination against the pre-#821 baseline; QualityMix now
compares QP's TimeAverage/Total with the live oracle on both SQL backends;
booted-runtime facts test expects 163.96 / 10.93.
- README recorded decision, ServerAggregateConfiguration remarks, oracle
remarks, docs/Historian.md and .claude/rules/historian.md updated.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
Condition events reaching one of our notifiers no longer go through the SDK
MonitoredNode2 channel: the walk serves the attached items itself, per item and
per event (audit guard, uncached INodeManager3 verdict, item gate/cut,
QueueEvent), as the Server-object path does. No notifier of ours defers any
more; the #838 deferral queue and the #854 cut stay as the safety net and
folder items share the cut (RefreshDirectItems, flag on and off). An event
whose walk suspends is marked deferred before it suspends.
Tests produce deferral with a notifier-stall probe instead of holding a folder
item's SDK lock (which would now block the reporter). New
FolderConditionRefreshWireTests; design note in docs/plans.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
The frozen 1.5.378.182 StatusAggregateCalculator counts Uncertain regions as
Good under TreatUncertainAsBad=false, so live AggregateFilter PercentGood /
DurationGood disagreed with HistoryRead (Part 13 §5.4.3.31/§5.4.3.33, Mantis
0006166) whenever Uncertain data was present. Owner-approved 2026-11-11.
- New app-owned GoodOnlyStatusAggregateCalculator subclasses the baseline and
replaces only the PercentGood/DurationGood computation (Good regions only);
CompatibilityAggregateFactory routes exactly those two IDs to it. The copied
SDK files are untouched; the other 35 aggregates are byte-identical.
- Golden test: the 64 changed vectors (38 PercentGood + 26 DurationGood) are
exempted exactly — those whose baseline output differs from the same case's
baseline TreatUncertainAsBad=true twin — and pinned to that twin (baseline
evidence, not regenerated from the implementation); plus a full Good-only
pin over all 352 PercentGood/DurationGood vectors and a hand-computed case.
- Live-vs-history parity over Good/Uncertain/Bad mixes (no masks), with a
discrimination check against the pre-#809 baseline; the booted-runtime facts
test now expects 8000 ms / 40 %.
- SdkAggregateOracle: Run/RunLive = the registered factory; RunSdkAsIs = the
untouched baseline; its Part13GoodCalculator duplicate is removed.
- README (recorded decision), ServerAggregateConfiguration remarks,
docs/Historian.md and .claude/rules/historian.md updated.
Claude-Session: https://claude.ai/code/session_01GT67AD99zQQqpLCVm3p7xk
Review of 1622d07f:
1. Perf: every i=2253 refresh ran the whole notifier walk + permission checks +
QueueEvent under Lock. Now, with nothing deferred (the common case), the refresh is
the SDK-shaped walk off Lock (Lock only to copy the root notifiers), kept only if no
deferral episode existed at any moment of it (count 0 before and after, episode
unchanged); otherwise the cut path also runs and its later replay supersedes. The
cut path takes ACL/role verdicts off Lock, then one short Lock hold: watermark +
frozen snapshots of Retain conditions from _alarmConditions (no tree walk) + per-item
cut and "replay pending" marker; the replay is queued OFF Lock, one event per hold of
the item gate. While pending, a condition event newer than the cut marks its
condition so the older frozen entry is dropped rather than following it. A
concurrent fast-path refresh cancels a pending cut replay of the same item.
Measured, 3000 retained conditions, longest Lock wait seen by another thread during
one refresh: 1622d07f 95-106 ms idle / 102-127 ms deferring; now 0-3 ms idle /
23-32 ms deferring.
2. ACL: a retained condition omitted from the replay for want of a grant is never
withheld (RefreshCut.RetainedAtCut); only Retain=true events of a condition omitted
because it was NOT retained are.
3. One gate/cut state per item for its lifetime (ConditionalWeakTable keyed by the
item): an unsubscribe + resubscribe between refresh and drain keeps the cut.
4. Cuts carry their deferral episode; ClearStaleRefreshCuts runs when the count
returns to zero, and a stale-episode cut is inert.
5. Dispose guard for the custom refresh (ObjectDisposedException once disposing;
Dispose waits for refreshes in flight).
6. Docs: a refresh waits at most for one in-progress QueueEvent on the item.
Tests: resubscribe variants, ACL-grant-lands test, pending-replay probe test,
dispose test, 3000-condition Lock-hold measurement with a probe pinning that neither
path queues its replay under Lock; stress invariant tightened (never backwards outside a
refresh; each refresh ends on the newest delivered state) and tolerant of the SDK's own
BadRefreshInProgress overlap refusal. Each new test fails against its targeted mutation.
While a folder subscriber's SDK channel is full, a condition's later events wait in
its #838 deferral queue and reach i=2253 items only when the drain gets to them, off
Lock. A ConditionRefresh in that window replayed the current state, then the older
deferred events followed RefreshEnd (stale state, or a condition the refresh had just
dropped re-added until the newest drained).
- Condition events are reported as ConditionEventSnapshot (an InstanceStateSnapshot
carrying a report sequence, condition NodeId and Retain); events queued behind a
deferred report are marked Deferred.
- Server-object refresh (ConditionRefresh and ConditionRefresh2, flag on AND off) now
runs in RefreshServerObjectItems: watermark, "anything deferred?", the replay and its
queueing in ONE Lock hold, so the replay is exactly the state at the cut. Per item it
queues the replay and installs a RefreshCut under the item's gate.
- OnConditionReportEvent holds that gate across "superseded? -> QueueEvent" for
deferred events only. Withheld from that item alone: events at/below the cut whose
condition the replay re-sent, or Retain=true events of a condition it omitted; an
older Retain=false event of an omitted condition is still delivered. Queues, other
Server-object items and folder items are untouched; refresh never waits for a drain.
- Lock order Lock -> item gate -> SDK item lock, same as a synchronous report.
- Meter otopcua.opcua.condition_events.superseded.
- Folder items keep a documented residual (SDK channel backlog + memoised per-item
verdict leave no per-event hook).
Tests: ConditionRefreshDeferralWireTests (deterministic overload by holding the folder
item's SDK lock; 6 variants fail before the fix; probe-driven gate test fails with the
gate removed; concurrent reports/refreshes/stall stress test fails before the fix).
#838 review of 91e28e87:
1. Ghost events. The deferred report ran the SDK walk off Lock with no
liveness check, so an event waiting behind a full channel when a deploy
removed its condition still reached i=2253 subscribers after the NodeDeleted
(a ghost Retain alarm for ScadaBridge) and folder items. Delivery now walks
the SDK path itself (OnReportEvent, OnReportEventAsync, inverse notifiers,
then the Parent as BaseInstanceState does) re-checking before EVERY hop that
the condition is the live instance; OnConditionReportEvent checks the same,
which also stops a non-live scripted condition being admitted through its
old equipment folder (#808). A guard test pins that only NodeState and
BaseInstanceState define the walk. New wire test removes the condition in
the same Lock hold as a flood; the flag-off variant fails without the checks.
2. Back-pressure. Deferral is per condition (one condition's events stay
ordered; others are not held up). Overflow policy: coalesce, newest wins --
past 1024 waiting per condition or 65,536 total, the oldest not-yet-started
event is discarded (a condition event carries full state). Warning on
entering deferral (<=1/min), Information on draining, meters
otopcua.opcua.condition_events.deferred / .discarded{reason}.
3. Verified by decompiling SDK 2.0.1: the notifier list is snapshotted under the
node's own lock, MonitoredNode2.Dispose completes its writer (pending writes
fail with ChannelClosedException, swallowed), and the consumer catches
per-event exceptions -- no fix needed; documented.
4. ConditionRefresh does not flush deferrals; documented as a residual.
#844 review: DescribeCredential canonicalises the key id (trim, lowercase;
non-hex ids fold into one identity) and the username, since ConfigDbApiKeyStore
matches with SQL Server's case-insensitive, trailing-space-blind `=`.
#838(a): each notifier's SDK MonitoredNode2 drains a bounded channel (4096,
FullMode=Wait) and the synchronous NodeState.ReportEvent blocks when it is
full. Condition events are reported under Lock, and the delivery task takes
Lock on a verdict-cache miss (the SDK's own GetNodeMetadata, flag off too, and
#826's IsNotifierEventVisibleTo). A burst of >4096 events under one Lock hold
therefore deadlocked the node manager -- FolderEventFloodWireTests stalled at
exactly 4097 events with enforcement on AND off (so it predates #826).
ReportConditionEvent now goes through ReportEventWithoutBlocking:
ReportEventAsync completes inline while channels have room (unchanged normal
path); on overflow the report continues asynchronously holding no thread or
lock, and later reports queue behind it so events keep report order. The
deferred work holds only frozen snapshots and drains once Lock is released;
client delivery stays bounded by each item's queue.
#838(b): documented in docs/security.md that Part 3 ReceiveEvents applies to
the event's EventType and SourceNode (the SDK check, kept first), not to the
notifier; our decision is layered on top and non-condition events on a folder
item fail closed under enforcement. The reflection item stays open.
#844: a success cleared the whole per-client count, so a client holding a valid
key could make four guesses at another key id, sign in with its own, and repeat
forever. Failures are now charged to the (client, credential identity) pair --
IOpcUaUserAuthenticator.DescribeCredential, key:<keyId> for API keys -- and to
the client as a whole. A success clears only its own identity's count; the
per-identity threshold locks that identity; a new per-client cap
(OpcUa:CredentialLockout:MaxFailedAttemptsPerClient, default 2 x
MaxFailedAttempts) that a success never resets bounds spraying across key ids
and locks every credential. Slots are bounded on both counts; a waiter whose
identity has room is not held behind one whose identity has none.
#845: (1) store timeouts, miss-budget refusals, store/authenticator exceptions,
an unset pepper and cancellation are reported Transient
(OpcUaUserAuthResult.Unavailable) and released uncounted, so a ConfigDb stall
can no longer lock every keyed client out; the client still sees the same
opaque denial. (2) a full 4096-entry table defers its next prune until the
earliest entry could age out instead of rescanning under the lock per failure.
(3) ApplicationUri deliberately NOT added to the key: on a None channel it is a
free string, so it would let an attacker reset the count per guess --
documented. (4) wire tests: distinct client certificates on a Sign endpoint are
locked out separately; the ApplicationConfigPath branch keeps the SDK lockout
off (falsified by removing the loaded-branch disable).
A legitimate consumer opening several keyed sessions at once from one key
(e.g. a ScadaBridge site node behind one NAT IP on a None endpoint) must
never see BadUserAccessDenied for parallelism. BeginAsync now hands out at
most MaxFailedAttempts - recordedFailures verification slots per key;
further activations queue FIFO and are woken as slots free. A waiter is
refused only when the key locks out (never reaching the authenticator) or,
uncounted, after OpcUa:CredentialLockout:SlotWaitSeconds (default 10,
BadTimeout). Cancelled waiters are dequeued; pruning accounts for waiters.
The security property is unchanged: no more than MaxFailedAttempts
unverified guesses in progress-or-failed per window.
- Reserve an in-flight slot per client before authenticating (TryBegin /
Complete / Abandon under one lock); refuse once recorded failures +
in-flight attempts reach MaxFailedAttempts, so a parallel burst cannot
pass the check before its first failure is recorded.
- An expired lockout resets the count (LockoutSeconds < FailureWindowSeconds
relocked on every single failure after the first lockout).
- Validate OpcUa:CredentialLockout at host start: disabled, or both
durations > 0.
- Log the first refusal of a lockout episode at Information, the rest at
Debug.
- Document that on None endpoints the key is effectively IP-only (NAT
neighbours share a UserName count) and a null peer shares one key.
1. Orphaned subscriptions (session closed without deleting subs) have Session == null, so the public
MonitoredNode2.InvalidatePermissionCacheForSession never reached their items: a cached allow survived a
deploy, the moved alarm's events were queued and delivered on TransferSubscriptions. Each notifier's
cache is now cleared whole through the SDK's private MonitoredNode2.InvalidatePermissionCaches
(reflection, guard-tested; fallback = per-session drop + Remove/Add of session-less items).
2. The verdict is decided on the condition LIVE under the event's NodeId, not the event's own instance:
the SDK key has no instance identity, so a replaced instance's late event cached a deny its successor
inherited until the next invalidation.
3. Invalidation is skipped while enforcement is off (forced across an on/off authorizer transition) and is
one O(cache) clear per node instead of a whole-cache scan per item.
4. TagReferencingEquipment carries alarm-bearing raw tags only (TagConfigIntent.Alarm); the snapshot adopts
an OrdinalIgnoreCase set instead of copying it again.
Tests (each fails with its fix reverted): FolderEventVerdictInvalidationTests (orphan + deploy + transfer;
replaced instance's late event; ACL-off skip; SDK private-method guard), DeploymentArtifactScopePathTests
(alarm-bearing projection).
Event items on an equipment / raw device folder were fed by the SDK's MonitoredNode2 fan-out with no ACL
decision, so after a deploy moved a scripted alarm (or dropped the reference projecting a native alarm into
an equipment) the OLD folder's subscribers kept receiving it - EventId included - until the rebuild landed,
indefinitely after a failed apply.
- OtOpcUaNodeManager re-implements INodeManager3 so ValidateEventRolePermissions (the SDK's per-event,
per-item hook; base not virtual) adds IsNotifierEventVisibleTo: live condition instance, notifier still a
legitimate notifier of it, and the #586/#808 Server-object rule (IsConditionVisibleTo over
ConditionVisibilityScopes).
- The SDK memoizes that verdict per (item, event type, SourceNode): InvalidateFolderEventVerdicts runs on the
authority/authorizer setters, RevalidateMonitoredItems (deploy + timer) and CompleteAddressSpaceApply.
- ConditionRefresh on direct items goes through RefreshDirectItems (base loop + the same decision).
- New generation field TagReferencingEquipment (RawPath -> EquipmentIds, from the artifact's
UnsTagReferences via AclScopePathResolver.ResolveTagRawPath): a native alarm's wired equipment folder only
counts (folder delivery AND Server-object scopes) while the current generation still references it.
- Secondary #808 edge: UNS variables wired UNS->Raw Organizes by AddReference are tracked and always placed
as reference variables (an Area named like its equipment's id no longer narrows them).
Tests: UnsFolderScopeWireTests (moved alarm on a folder item + ConditionRefresh + rebuild; area named like
equipment id), NativeAlarmFolderEventAclWireTests (dropped reference: folder + Server object + refresh +
restore), DeploymentArtifactScopePathTests (projection). Rig/event tests now supply tag references.
OPC Foundation SDK 2.0.1's SessionManager lockout refused EVERY
activation (Anonymous included, before the token is read) from a client
with 5 failed identity validations in 60 s, for 5 minutes, keyed on cert
thumbprint else peer IP. Disable it (MaxFailedAuthenticationAttempts=0
on built and loaded configs) and enforce FailedCredentialLockout in the
identity-registry adapter instead: UserName activations only, keyed on
thumbprint+peer together, same 5/60s/300s defaults, configurable via
OpcUa:CredentialLockout.
Review of af5c9744:
1. UNS reference variables (s=Area/Line/Equip/Eff) of a moved or renamed
equipment stayed readable/writable under the OLD names' grants: they now
resolve as ReferenceVariable and are authorized at their split path only
while it equals their live equipment folder's placement (live chain ==
generation chain) + one name; otherwise denied (Read and Write).
2. TryPlaceScriptedCondition now also requires the owner folder's live chain
to match the generation (AuthorizeScriptedCondition gains ownerFolderChain),
so a moved equipment's alarm/children/commands follow its folder.
3. Identifiers containing NUL are denied before the decision cache, keeping
client ids disjoint from the NUL-prefixed resolved-scope keys (a client
could otherwise poison a real folder's cached verdict for its key shard).
4. An id no live node holds is Unknown: placed at [\0unknown] so only
Cluster / Namespace-uns grants decide it (a removed opaque id can no longer
split onto a same-named narrow grant; narrow grantees get no NodeDeleted for
removed UNS folders/vtags/conditions — documented); 4-segment
reference-shaped ids keep their split.
5. A wire test drives placements from DeploymentArtifact.ParseDataPlaneAuthority.
Baseline updates: #797 owner tests (unit + wire) and Sdk2RepeatedAlarmAuthority
now install folder scopes; Sdk2HistoryAuthority's UNS alias used the RAW path
as its UNS id (never minted in production) and now carries EqA/HistoryAlias.
Each new guard was falsified (reverting it fails its test).
UNS Area/Line/Equipment folders are minted under their opaque entity ids
(s=UA-/UL-/EQ-...), virtual tags under s=EQ-.../Name and scripted conditions
(+ #629 children) under s=<ScriptedAlarmId>[/...], while every UNS grant is
planted at a NAME path. DataPlaneAuthorizer split those ids, so with
Security:Acl:Enabled a narrow (Area/Line/Equipment) grant could not Browse,
Read, subscribe or HistoryRead them, and Server-object delivery never reached
it — so a narrow key never held the EventId Ack/Confirm/AddComment need.
- The generation carries UnsFolderScopes (folderId -> path + id chain), built
by DeploymentArtifact from the same AclScopePathResolver as the grants; ids
two entity kinds share are dropped; plumbed through IDataPlaneAuthoritySink.
- OtOpcUaNodeManager.ResolveUnsAclSubject reports live facts (folder id
ancestry / scripted owner binding); attached by the Authorizer setter.
- Evaluate places the subject against the CURRENT generation before the
decision cache, which now caches the walk keyed on the resolved scope.
Folders require live chain == generation chain (a moved equipment is denied
under old and new line until the rebuild). Owned nodes (vtags, conditions,
children) get owner path + a reserved segment, so Tag grants and their
Browse transit never expose them. Conditions share TryPlaceScriptedCondition
with the #797 command gate.
- Server-object visibility of a scripted condition is decided on the
condition alone, so a moved alarm cannot reach its old owner there.
Tests: UnsFolderScopeWireTests (opaque ids, end-to-end browse -> EventId ->
Acknowledge on an Equipment grant; sibling denied; Tag-only grant; moved alarm
and moved equipment stale windows). Rig tests now install folder scopes
explicitly (ServerEventRig.FolderScopes); the #797 recreate test deliberately
asserts the moved alarm is invisible to the Cluster observer in the window.
Review of 3d1b86b4: OpcUaPublishActor installs a new authority generation
before applying its address space, and an apply that throws keeps the old one.
A scripted alarm moved from equipment A to B therefore stayed commandable with
A's grant under B's generation (briefly before the rebuild, or indefinitely
after a failed apply).
The generation now carries ScriptedAlarmOwners (ScriptedAlarmId -> EquipmentId,
decoded by ParseDataPlaneAuthority from the artifact's ScriptedAlarms rows, the
same rows the composition materialises from). AuthorizeScriptedCondition denies
unless the node manager's live binding names the same owner as the generation:
a moved alarm is denied under the old owner's, the new owner's and a Cluster
grant until the address space re-binds it; an alarm the generation no longer
deploys is denied. Install/apply order unchanged.
Tests: window (a) generation moved / binding stale => both owners and Cluster
denied, then rebuild under the new owner => new owner allowed, old denied;
window (b) apply failed after install => denied across clock and further
generations, then a successful rebuild restores the new owner only; undeployed
alarm denied; artifact decode of the owner map.
Scripted condition NodeIds are opaque ScriptedAlarmIds, so splitting them as a
topology path could never match an Equipment grant: a narrow equipment grant was
denied while a Cluster grant passed.
- OtOpcUaNodeManager binds each LIVE scripted condition instance to the
EquipmentId it was materialised under (only when it hangs under that folder);
dropped on remove / drop-recreate / equipment-subtree removal / rebuild; a
same-id re-materialise under another equipment re-parents and re-binds.
- DataPlaneAuthoritySnapshot carries EquipmentScopePaths (EquipmentId ->
[uns, Area, Line, Equipment]) decoded from the artifact by the same
AclScopePathResolver call that plants Equipment grants.
- DataPlaneAuthorizer.AuthorizeScriptedCondition re-reads key, grant and
generation per call (uncached) and evaluates at the owner path; unbound,
replaced or unplaceable owners deny under every grant. No id-split or
realm-root fallback.
- Native conditions (RawPath) and the ACL-off role gate are unchanged.
NodeIds and AlarmCommand.AlarmId are unchanged.
Sdk2OpaqueScriptedScopeBaselineTests deliberately flipped: it pinned the denial
and now pins owner-grant allow / sibling deny / cluster allow. Follow-up #808
(folder ids + Server-object event visibility for narrow UNS grants).
Joseph Doherty