# WCF Status Evidence

Commands:

```powershell
dotnet run --no-build --project tools\AVEVA.Historian.ReverseEngineering -- wcf-status localhost 32568
dotnet run --no-build --project tools\AVEVA.Historian.ReverseEngineering -- wcf-status localhost 32568 Version
```

Confirmed:

- The local status endpoint is `net.tcp://localhost:32568/Stat`.
- `IStatusServiceContract2` is a static WCF contract named `Stat` in namespace
  `aa`. The managed definitions now include `GetSystemParameter`, `GETHI`,
  `PNGS`, and `PNGP`.
- `GetInterfaceVersion` returns code `0`, version `0` on the local 2020
  install.
- The decompiled `CStatusConnectionWCF.GetServerTime` implementation is a
  WCF-path stub that returns success without calling the `Stat` service. The
  managed direct call likewise returns code `0` with size `0` and no buffer.

Observed sanitized localhost results:

- `GetSystemTimeZoneName(handle: 0)` returns code `4` and no value.
- `IsDBCaseSensitive(handle: 0)` returns code `4`.
- `GetSystemParameter(handle: 0, "Version")` returns `false` with no error
  buffer.

Re-tested 2026-06-20 with a **real authenticated client handle** (full Open2 auth
chain), not `handle: 0`:

- `GetSystemParameter(handle, "HistorianVersion")` → real version string (works;
  shipped as `GetSystemParameterAsync`).
- `GetSystemTimeZoneName(handle)` → return code `0x00000000` (success) but an
  **empty value string**. Same channel/handle that makes `GetSystemParameter`
  return real data, so this is the op's own behavior, not an auth/marshalling
  gap. `GetSystemTimeZoneName` is a member of the `GetServerTime` stub family:
  the 2020 WCF path returns success without producing a value (the native client
  computes the zone locally). It only becomes a real round-trip on the 2023 R2
  gRPC front door (`Status.GetSystemTimeZoneName`), which is absent on this box.

Interpretation:

- `Stat` endpoint routing is confirmed, but status operations that require a
  real client handle are not usable until managed session open is solved.
- `GetServerTime` should not be promoted into the public SDK as a real server
  time call from this WCF path; native evidence shows it is a no-op stub here.
- **`GetServerTimeZoneAsync` (roadmap R1.3) is NOT a trivial WCF op on 2020** — it
  is a stub returning empty. Do not ship it over the 2020 WCF transport. Deliver
  it only against a live 2023 R2 gRPC server. Reclassified in `docs/plans/hcal-roadmap.md`.

## GETRP / GetRuntimeParameter (roadmap R1.2) — DONE, live-verified 2026-06-20

Captured the native `HistorianAccess.GetRuntimeParameter(List<string>, out List<object>)`
WCF traffic with `scripts/Capture-RuntimeParam.ps1` (instrument-wcf-{write,read}message).
Findings:

- The WCF op is **`aa/Stat/GETRP`** — `bool GETRP(string handle, byte[] pRequestBuff,
  out byte[] pResponseBuff, out byte[] errorBuffer)`, i.e. the **same string-handle +
  request/response-buffer shape as GETHI**, *not* the simple `GetSystemParameter(uint, string)`
  shape the roadmap originally assumed.
- The `string handle` is the **Open2 storage-session GUID** (the value
  `ParseOpenConnectionResponse` reads from `outBuff[5..21]`), sent **UPPERCASE, dash-separated,
  no braces** (`ToString("D").ToUpperInvariant()`).
- Unlike GETHI (which the earlier probe found blocked), **GETRP succeeds from the pure-managed
  client** with that handle: `GetRuntimeParameter("HistorianVersion")` → `20,0,000,000`.
- `pRequestBuff` = `54 67 01 00` (sig+version) + uint nameCount + per name(uint charCount +
  UTF-16LE). `pResponseBuff` = version(1) + uint resultCount + CRetVariant(`0x43` VT_BSTR +
  uint16 payloadLen + uint16 charCount + UTF-16LE).

Shipped as `HistorianClient.GetRuntimeParameterAsync(name)`. See
`HistorianRuntimeParameterProtocol`, golden `WcfRuntimeParameterProtocolTests`, and the
handle-format lead in `wcf-string-handle-wall.md` §Update (retry GETHI/ExeC uppercased).