Files
mxaccess/rust
Joseph Doherty af15fe7587 [F49 step 1 + F56] callback router: peel envelope before parsing subscription / 0x11 frames
The router used to call NmxSubscriptionMessage::parse_inner directly
on the COM-stub-delivered body, but the wire bytes arrive wrapped in
a ProcessDataReceived envelope (46-byte header + optional 4-byte
length prefix); parse_inner expects post-envelope bytes. Result:
every 0x33 DataUpdate that ever arrived was silently dropped.

Mirrors the .NET reference's MxNativeSession.OnCallbackReceived flow
at cs:582-606 — three sequential parse attempts:
  1. NmxOperationStatusMessage::try_parse_process_data_received_body  (already wired)
  2. NmxReferenceRegistrationResultMessage::try_parse_...              (NEW — was missing)
  3. NmxSubscriptionMessage::try_parse_process_data_received_body      (NEW — was wrong)

Adds:
- NmxSubscriptionMessage::try_parse_process_data_received_body — peels
  envelope via NmxObservedEnvelope::parse_process_data_received_body_flexible,
  then dispatches to existing parse_inner.
- NmxReferenceRegistrationResultMessage::try_parse_process_data_received_body —
  same shape, for the 0x11 registration-result frame.
- Router branch for 0x11 — currently traces the assigned item_handle and
  drops the frame (matches the .NET reference, which fires a
  ReferenceRegistrationReceived event with no consumer in the codebase).
- Router fall-through trace! when neither path matches, so future
  unparseable bodies surface in RUST_LOG=trace instead of vanishing.
- DcomCallbackSink::forward — trace! per inbound callback so
  RUST_LOG=mxaccess_callback=trace surfaces opnum + size.
- crates/mxaccess-compat/tests/buffered_subscribe_live.rs — F49 step 1
  live test that drives subscribe_buffered + a 500ms-cadence writer.
  Also pulls tracing-subscriber as a dev-dep so the test can dump
  router activity.

Existing router_task_decodes_callback_invoked_into_broadcast unit test
updated to wrap its synthetic 0x32 body in an envelope so the new
parse path actually accepts it.

Live result: F56 — the buffered round-trip *registers* successfully
(RegisterReference returns HRESULT 0; engine sends one 0x11
RegistrationResult + one 51-byte op-status per write, perfectly
clocked) but the engine never sends a 0x33 DataUpdate. Rust-port-
specific gap vs the .NET reference's working buffered path; root
cause is likely a field-level difference in the RegisterReference
body or a missing post-RegisterReference step. Captured as F56 in
design/followups.md, blocking F49 step 1; F56's DoD is the same
live test reporting >=3 DataChange arrivals.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-06 09:50:57 -04:00
..

mxaccess (Rust port)

Native Rust replacement for AVEVA / Wonderware MXAccess. See ../design/ for the architectural specification, ../src/ for the .NET reference (the executable spec), and ../CLAUDE.md for project-wide rules.

Status

M0 — Workspace skeleton. Stub types compile; nothing is implemented yet. See ../design/60-roadmap.md for the M0M6 milestone plan.

Layout

rust/
  Cargo.toml                 workspace root
  rust-toolchain.toml        1.85 stable
  crates/
    mxaccess-codec/          pure protocol codec, no I/O
    mxaccess-galaxy/         Galaxy SQL resolver (tiberius)
    mxaccess-rpc/            DCE/RPC + NTLMv2 + OXID + OBJREF
    mxaccess-callback/       INmxSvcCallback RPC server
    mxaccess-nmx/            INmxService2 client
    mxaccess-asb-nettcp/     net.tcp framing (MC-NMF + MC-NBFX/NBFS)
    mxaccess-asb/            IASBIDataV2 client
    mxaccess/                async session + Transport trait + public API
    mxaccess-compat/         LMXProxyServer-shaped facade

Build

cargo build --workspace
cargo test --workspace
cargo clippy --workspace -- -D warnings
cargo fmt --check

Live probes

. ..\tools\Setup-LiveProbeEnv.ps1
cargo test -p mxaccess --features live -- --ignored

The setup script fetches credentials from Infisical via wwtools/secrets/Get-Secret.ps1. Never inline plaintext credentials.

License

MIT — see ../LICENSE.