Joseph Doherty
d5bd4226ee
Task 26 — the P2 milestone gate. Ran the live /run verification on an isolated
docker-dev rig (project otopcua-mqtt, ports 9210/4850-4851/14350, image built
from this branch) against the real Mosquitto TLS+auth broker and the C#
Sparkplug edge-node simulator on 10.100.0.35, and recorded the result.
The gate found three defects. Two are the same defect class the P1 gate found
twice — a hand-maintained AdminUI surface left behind by a driver-side feature —
and the third is a pre-existing cross-driver bug that only a Sparkplug flow
could surface.
1. CRITICAL, FIXED — MqttDriverForm still shipped its P1 Sparkplug PLACEHOLDER.
Switching Mode to SparkplugB rendered a "not available yet" notice and NO
Group ID field, so with Sparkplug ingest fully shipped there was still no
way to author a Sparkplug driver from the AdminUI at all. Sparkplug.GroupId
is the driver's entire subscription filter (spBv1.0/{GroupId}/#): blank ⇒
connected, Healthy, ingesting nothing. Now authors all five Sparkplug keys,
MERGES over the existing sub-object rather than replacing it (so a key a
newer driver adds inside it survives an older AdminUI), leaves it untouched
in Plain mode, and validates the group id as the topic segment it is.
Pinned by 8 MqttDriverFormModelTests cases, verified falsifiable — 8 RED
with the fix stubbed out.
2. PRE-EXISTING + CROSS-DRIVER, FIXED — every node label in the shared
DriverBrowseTree was an <a href="#">. In a Blazor Web App, blazor.web.js's
enhanced-navigation click interceptor resolves a bare "#" against
<base href="/">, so clicking ANY browse-tree node label navigated the whole
AdminUI to "/", tore down the circuit, and destroyed the hosting modal —
losing the browse session AND the tag selection. @onclick:preventDefault
does not help: it suppresses the browser's default action, not Blazor's own
interceptor. Labels are now <button type="button">. Dates to the component's
introduction (2026-05-28) and affects EVERY driver's picker; it surfaced
only now because choosing a rebirth scope is the first flow that requires
clicking a label rather than the ▶ toggle (always a button, always fine).
3. FIXED (mitigation) — the browse tree rendered exactly once, at open, and
never again, while OpenAsync returns as soon as the SUBSCRIBE is granted.
On Sparkplug that means it is almost always empty forever, because births
are never retained. Added a Refresh button that re-reads the root against
the SAME session (nothing reconnects, nothing observed is lost, the tag
selection is kept, only the armed rebirth scope is cleared).
Live gate result (all against the real broker + simulator, group OtOpcUaSim):
- driver authored end-to-end through the fixed MqttDriverForm; blob is
Mode:SparkplugB + Sparkplug.GroupId:OtOpcUaSim with enums as names
- browse: BROWSER OPEN chip, Sparkplug-only rebirth panel, tree renders
Group → EdgeNode → [Device] → Metric with the device folder Filler1 and
node-level metric leaves SIDE BY SIDE, and "Node Control/Rebirth" as ONE
leaf (the metric-name-is-not-a-topic-segment rule holding)
- rebirth: group scope names the group + the 32-node cap, Cancel published
NOTHING (simulator log unchanged); edge-node scope → "1 command published"
and the simulator logged "rebirth NCMD #1 received; republishing metadata";
group scope → "2 commands published", both edge nodes re-birthed; a device
and a metric both resolve UP to "edge node EdgeA"; the panel does NOT render
for a Plain MQTT device
- browse-commit wrote bindable tuples with no topic/address key —
{"groupId","edgeNodeId","metricName","deviceId"} for the device metric and
deviceId ABSENT (not blank) for the node-level one, datatypes inherited from
the birth (Int64 / Float)
- deployed (Sealed), and both nodes served live changing values through OPC UA
at the 2 s cadence — Good 0x00000000, no BadNodeIdUnknown
- death→STALE: stopping the simulator drove both nodes to 0x80000000 with an
empty value ~2 s later, and restarting it recovered them to Good on the new
birth (FillCount back to its birth-declared 1000, then counting)
- rediscovery fired exactly TWICE (once per authored scope: OtOpcUaSim/EdgeA
7 metrics, OtOpcUaSim/EdgeA/Filler1 3 metrics) and was then gated across
many subsequent births/rebirths — the anti-storm change gate working, and
EdgeB correctly filtered out as an unauthored scope
- tag editor: opens in SparkplugB (mode inference on reopen) with all four
descriptor fields populated; blank group → "A Sparkplug group ID is
required."; "Plant/1" rejected; "Node Control/Rebirth" ACCEPTED and saved
with the slash whole; dataType override persists and its key is ABSENT again
after selecting "(from birth certificate)"
Two things are NOT verified, and are recorded rather than claimed:
- Rediscovery is INERT in v3 and this is a platform gap, not an MQTT one:
nothing subscribes to IRediscoverable.OnRediscoveryNeeded and
DriverHostActor.HandleDiscoveredNodes hard-returns. A DBIRTH introducing a
metric does NOT change the OPC UA tree; redeploy. Verified from the driver's
log line only, exactly as far as it can be verified.
- A metric name containing "/" cannot be BROWSE-COMMITTED: the derived raw tag
Name is a RawPath segment and may not contain "/", so the spec-mandatory
"Node Control/Rebirth" is refused ("Row 3: Name must not contain '/'"). The
refusal is loud and all-or-nothing, never a silently mis-bound tag, and
Manual entry is the working path. Fixing it needs a name-sanitisation policy
with a collision answer, so it was recorded rather than guessed at.
Also left open + documented: an empty browse tree cannot arm a rebirth (the
scope comes from a tree click, and the session side already accepts a bare
{group}/{edgeNode} — only a UI path is missing); _canRebirth is captured at
browse-open; the tag editor injects the Plain-only payloadFormat key into a
Sparkplug blob (cosmetic — the factory routes on the tuple).
Suites: offline 1528 passed / 0 failed (581 Driver.Mqtt + 809 AdminUI + 138
Core.Abstractions); live 15/15 against the broker + simulator.
Docs: docs/drivers/Mqtt.md brought fully up to date for P2 (Sparkplug config
sub-object, both tag shapes, the ingest state machine, rediscovery, browse +
rebirth + Refresh, a Known-gaps table); Mqtt-Test-Fixture.md gains the simulator
and drops its "Sparkplug has no fixture" claims; infra/README.md §3 gains the
simulator row; CLAUDE.md gains the simulator endpoint facts; the tracking doc
marks MQTT/Sparkplug COMPLETE. docker-dev/docker-compose.mqtt.yml is the
isolated-rig overlay the gate ran on.
Claude-Session: https://claude.ai/code/session_01GASWkNEi68FSCtvr6rLoEW
OtOpcUa
OPC UA server (.NET 10 AnyCPU) that exposes a fleet of industrial drivers as a single OPC UA address space. Drivers ship in-process for AVEVA System Platform Galaxy (via the sibling mxaccessgw repo), Modbus TCP, Siemens S7, Allen-Bradley CIP (ControlLogix / CompactLogix), Allen-Bradley Legacy (SLC 500 / MicroLogix), Beckhoff TwinCAT (ADS), FANUC FOCAS, OPC UA Client (gateway), and MQTT (broker subscribe; Sparkplug B in progress).
A cross-platform client stack (.NET 10) — shared library, CLI, and Avalonia desktop app — connects to any OPC UA server.
Architecture
OPC UA Clients (CLI, Desktop UI, 3rd-party)
|
v
+-------------------------------------+
| OtOpcUa.Server (.NET 10 AnyCPU) |
| address space + capability fan-out|
+-------------------------------------+
| | | | | | | |
Galaxy Modbus S7 AbCip AbLeg TwinCAT FOCAS OpcUaClient MQTT
|
v
mxaccessgw (sibling repo, gRPC)
|
v
MXAccess COM (x86 worker, on AVEVA box)
Galaxy is the only driver with an external runtime: it speaks gRPC to a separately installed mxaccessgw server (sibling repo at c:\Users\dohertj2\Desktop\mxaccessgw\) which owns the MXAccess COM apartment and the x86/STA bitness constraint server-side. Everything in this repo is platform-agnostic .NET 10.
Prerequisites
- .NET 10 SDK (server, drivers, clients all target .NET 10)
- SQL Server reachable for the central config DB
- For Galaxy specifically: a running
mxaccessgwdeployment — see docs/v2/Galaxy.ParityRig.md - For historian read-back / alarm history / continuous historization: a running
ZB.MOM.WW.HistorianGatewaydeployment (the sole historian backend; consumed as theZB.MOM.WW.HistorianGateway.ClientgRPC package). It must runRuntimeDb:Enabled=true+RuntimeDb:EventReadsEnabled=true, and the API key must carryhistorian:read+historian:write+historian:tags:writescopes.
Quick Start
dotnet restore ZB.MOM.WW.OtOpcUa.slnx
dotnet build ZB.MOM.WW.OtOpcUa.slnx
dotnet test ZB.MOM.WW.OtOpcUa.slnx
# Run the server in dev (foreground)
dotnet run --project src/Server/ZB.MOM.WW.OtOpcUa.Host
The server starts on opc.tcp://localhost:4840 with the None security profile. Configure Security.Profiles in src/Server/ZB.MOM.WW.OtOpcUa.Host/appsettings.json to enable Basic256Sha256-Sign or Basic256Sha256-SignAndEncrypt. See docs/security.md.
Install as Windows Services
Production deployment is driven by scripts/install/Install-Services.ps1, which registers the OtOpcUa server service under a chosen service account. Historian support requires a separately deployed ZB.MOM.WW.HistorianGateway and Galaxy support a separately installed mxaccessgw — neither this repo nor the install script provisions them.
.\scripts\install\Install-Services.ps1 `
-InstallRoot 'C:\Program Files\OtOpcUa' `
-ServiceAccount 'DOMAIN\svc-otopcua'
The historian backend is the external ZB.MOM.WW.HistorianGateway (not installed by this script). See the script header and docs/ServiceHosting.md for full options.
Client CLI
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- connect -u opc.tcp://localhost:4840
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- browse -u opc.tcp://localhost:4840 -r -d 3
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- read -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode"
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- write -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode" -v 42
dotnet run --project src/Client/ZB.MOM.WW.OtOpcUa.Client.CLI -- subscribe -u opc.tcp://localhost:4840 -n "ns=2;s=SomeNode" -i 500
See docs/Client.CLI.md and docs/Client.UI.md.
Documentation
Architecture deep-dives
| Topic | Doc |
|---|---|
| OPC UA server composition, namespace fan-out, Polly invoker | docs/OpcUaServer.md |
| Address space layout | docs/AddressSpace.md |
| Read / Write dispatch (driver vs virtual vs scripted-alarm) | docs/ReadWriteOperations.md |
| Incremental sync (driver-backend rediscovery + config publishes) | docs/IncrementalSync.md |
| Service hosting (Server + Admin; external HistorianGateway backend) | docs/ServiceHosting.md |
| Security (transport, LDAP, certificates) | docs/security.md |
| Redundancy | docs/Redundancy.md |
| Status dashboard | docs/StatusDashboard.md |
Drivers
| Topic | Doc |
|---|---|
| Driver specs (per-driver capability surface, config, addressing) | docs/v2/driver-specs.md |
| Galaxy driver | docs/drivers/Galaxy.md |
| Modbus / S7 / AbCip / AbLegacy / TwinCAT / FOCAS / OpcUaClient / MQTT | docs/drivers/ |
| Galaxy parity rig (mxaccessgw setup) | docs/v2/Galaxy.ParityRig.md |
| Galaxy performance + tracing | docs/v2/Galaxy.Performance.md |
Clients
| Topic | Doc |
|---|---|
| Client CLI | docs/Client.CLI.md |
| Client UI (Avalonia desktop) | docs/Client.UI.md |
v1 archive
The original v1 in-process MXAccess docs (Galaxy.Host topology, Configuration env vars, AlarmTracking, DataTypeMapping, HistoricalDataAccess, Subscriptions, etc.) are preserved under docs/v1/ — historical reference only. PR 7.2 retired the v1 architecture on 2026-04-30; current state is documented in the sections above.
License
Internal use only.