dohertj2/lmxopcua
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Extract historian into a runtime-loaded plugin so hosts without the Wonderware SDK can run with Historian.Enabled=false

Browse Source 
The aahClientManaged SDK is now isolated in ZB.MOM.WW.LmxOpcUa.Historian.Aveva and loaded via HistorianPluginLoader from a Historian/ subfolder only when enabled, removing the SDK from Host's compile-time and deploy-time surface.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
Joseph Doherty
2026-04-12 15:16:07 -04:00
parent 9e1a180ce3
commit 9b42b61eb6
40 changed files with 739 additions and 15855 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
docs/ServiceHosting.md
View File

@@ -61,7 +61,7 @@ This is necessary because Windows services default their working directory to `S
5. **Create and connect MXAccess client** -- Starts the STA COM thread, creates the `MxAccessClient`, and attempts an initial connection. If the connection fails, the service logs a warning and continues -- the monitor loop will retry in the background.
6. **Start MXAccess monitor** -- Starts the connectivity monitor loop that probes the runtime connection at the configured interval and handles auto-reconnect.
7. **Test Galaxy repository connection** -- Calls `TestConnectionAsync()` on the Galaxy repository to verify the SQL Server database is reachable. If it fails, the service continues without initial address-space data.
8. **Create OPC UA server host** -- Creates `OpcUaServerHost` with the effective MXAccess client (real, override, or null fallback), performance metrics, and optional historian data source.
8. **Create OPC UA server host** -- Creates `OpcUaServerHost` with the effective MXAccess client (real, override, or null fallback), performance metrics, and an optional `IHistorianDataSource` obtained from `HistorianPluginLoader.TryLoad` when `Historian.Enabled=true` (returns `null` if the plugin is absent or fails to load).
9. **Query Galaxy hierarchy** -- Fetches the object hierarchy and attribute definitions from the Galaxy repository database, recording object and attribute counts.
10. **Start server and build address space** -- Starts the OPC UA server, retrieves the `LmxNodeManager`, and calls `BuildAddressSpace()` with the queried hierarchy and attributes. If the query or build fails, the server still starts with an empty address space.
11. **Start change detection** -- Creates and starts `ChangeDetectionService`, which polls `galaxy.time_of_last_deploy` at the configured interval. When a change is detected, it triggers an address-space rebuild via the `OnGalaxyChanged` event.
@@ -153,21 +153,37 @@ See [Redundancy Guide](Redundancy.md) for full deployment details.
## Required Runtime Assemblies
The build uses Costura.Fody to embed all NuGet dependencies into the single `ZB.MOM.WW.LmxOpcUa.Host.exe`. However, the following ArchestrA and Historian DLLs are **excluded from embedding** and must be present alongside the executable at runtime:
The build uses Costura.Fody to embed all NuGet dependencies into the single `ZB.MOM.WW.LmxOpcUa.Host.exe`. The only native dependency that must sit alongside the executable in every deployment is the MXAccess COM toolkit:
| Assembly | Purpose |
|----------|---------|
| `ArchestrA.MxAccess.dll` | MXAccess COM interop — runtime data access to Galaxy tags |
| `aahClientManaged.dll` | Wonderware Historian managed SDK — historical data queries |
| `aahClient.dll` | Historian native dependency |
| `aahClientCommon.dll` | Historian native dependency |
| `Historian.CBE.dll` | Historian native dependency |
| `Historian.DPAPI.dll` | Historian native dependency |
| `ArchestrA.CloudHistorian.Contract.dll` | Historian contract dependency |
These DLLs are sourced from the `lib/` folder in the repository and are copied to the build output directory automatically. When deploying, ensure all seven DLLs are in the same directory as the executable.
The Wonderware Historian SDK is packaged as a **runtime-loaded plugin** so hosts that will not use historical data access do not need the SDK installed. The plugin lives in a `Historian/` subfolder next to `ZB.MOM.WW.LmxOpcUa.Host.exe`:
These assemblies are not redistributable — they are provided by the AVEVA System Platform and Historian installations on the target machine. The copies in `lib/` are taken from `Program Files (x86)\ArchestrA\Framework\bin` on a machine with the platform installed.
```
ZB.MOM.WW.LmxOpcUa.Host.exe
ArchestrA.MxAccess.dll
Historian/
ZB.MOM.WW.LmxOpcUa.Historian.Aveva.dll
aahClientManaged.dll
aahClientCommon.dll
aahClient.dll
Historian.CBE.dll
Historian.DPAPI.dll
ArchestrA.CloudHistorian.Contract.dll
```
At startup, if `Historian.Enabled=true` in `appsettings.json`, `HistorianPluginLoader` probes `Historian/ZB.MOM.WW.LmxOpcUa.Historian.Aveva.dll` via `Assembly.LoadFrom` and instantiates the plugin's entry point. An `AppDomain.AssemblyResolve` handler redirects the SDK assembly lookups (`aahClientManaged`, `aahClientCommon`, …) to the same subfolder so the CLR can resolve them when the plugin first JITs. If the plugin directory is absent or any SDK dependency fails to load, the loader logs a warning and the server continues to run with history support disabled — `LmxNodeManager` returns `BadHistoryOperationUnsupported` for every history call.
Deployment matrix:
| Scenario | Host exe | `ArchestrA.MxAccess.dll` | `Historian/` subfolder |
|----------|----------|--------------------------|------------------------|
| `Historian.Enabled=false` | required | required | **omit** |
| `Historian.Enabled=true` | required | required | required |
`ArchestrA.MxAccess.dll` and the historian SDK DLLs are not redistributable — they are provided by the AVEVA System Platform and Historian installations on the target machine. The copies in `lib/` are taken from `Program Files (x86)\ArchestrA\Framework\bin` on a machine with the platform installed.
## Platform Target