Files
mxaccess/design
Joseph Doherty e5b31fadb1
rust / build / test / clippy / fmt (push) Has been cancelled
rust / cargo public-api drift check (F41) (push) Has been cancelled
[F49] live-test scaffolding for F54 OnWriteComplete + COM probe diagnostic
Live attempt against AVEVA on this dev host produced two artefacts:

**`crates/mxaccess-compat/tests/lmx_write_complete_live.rs`** — the
F54 OnWriteComplete round-trip test. Compiles + runs against the
live AVEVA install via either path:
- `--features live-windows-com` (preferred): uses
  `Session::connect_nmx_auto` so the COM activation reference is
  held in-process for the duration of the test.
- Default features (fallback): shells out to
  `MxNativeClient.Probe --probe-resolve-oxid-managed-ntlm-integrity`
  + `--probe-remqi-managed` to learn the per-session NMX endpoint +
  INmxService2 IPID, then uses `Session::connect_nmx`.

Both code paths are wired and the test runs through endpoint
resolution + IPID extraction successfully. The connect step itself
fails with `Status { detail: 1722 }` (RPC_S_SERVER_UNAVAILABLE).

**`crates/mxaccess-rpc/examples/com-marshal-probe.rs`** — minimal
one-shot binary that calls
`marshal_activated_iunknown_objref("NmxSvc.NmxService",
DifferentMachine)` in isolation. Confirms the COM activation +
CoMarshalInterface chain works fine standalone (returns a 338-byte
OBJREF with valid OXID/IPID structure). The 1722 in the live test
is therefore downstream of the activation — likely a COM-apartment
threading interaction with the tokio multi-thread runtime.

This is an F12-related issue (auto-resolve hardening), not an F54
issue. F54's correctness is covered by the existing unit-level
integration tests:
- `mxaccess::session::tests::router_populates_operation_status_context_from_pending_ops_fifo`
- `mxaccess::session::tests::write_handle_correlates_with_router_emitted_status`
- `mxaccess_compat::tests::drain_routes_write_status_to_on_write_complete`
- `mxaccess_compat::tests::drain_routes_non_write_status_to_on_operation_complete`

`design/followups.md` F49 entry updated to reflect:
- F54 added as a fifth row in the live-verification scope.
- "Live attempt 2026-05-06" sub-section documents the 1722 issue +
  what was verified (.NET probe end-to-end works against same
  install; Rust COM activation works in isolation; the failure is
  Rust-port-specific to `connect_nmx_auto` under tokio).
- F49 now Blocked-by F12 hardening (the 1722 path).

New `live-windows-com` feature on `mxaccess-compat` propagates to
`mxaccess/windows-com` for the test binary.

Workspace 824 → 824 tests; clippy + rustdoc clean across both
feature configurations.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-06 08:23:01 -04:00
..

design/ — Rust port architectural plan

This folder is the design contract for the Rust replacement of AVEVA/Wonderware MXAccess. It is the gap between the .NET reference in src/ and the Rust crates that will be written under a sibling rust/ workspace (per CLAUDE.md).

The folder is structured as a small set of focused documents. Read in order; each builds on the previous.

File Purpose
00-overview.md Mission, two-layer goal, architectural principles, non-goals
10-raw-layer.md Byte-accurate raw MXAccess layer (codec + transport + session)
20-async-layer.md Idiomatic Tokio async layer on top of the raw layer
30-crate-topology.md Cargo workspace, crates, dependencies, build/test commands
40-protocol-invariants.md Bill of materials: IIDs, opnums, envelope/handle bytes
50-error-model.md MxStatus, error types, panic/cancellation policy
60-roadmap.md Milestones M0..M6, validation strategy
70-risks-and-open-questions.md Parity gaps, unproven flows, cross-platform constraints
dependencies.md Cross- and within-milestone parallelism map; agent budget per phase
review.md Adversarial review log (BLOCKER/MAJOR/MINOR/NIT findings, all resolved)
prompt.md /loop driver prompt for autonomous M2M6 execution
followups.md Open / resolved deferred work items; auto-triaged by prompt.md Step 0 (created on first /loop run if missing)

The design is grounded in the .NET reference at src/ and the protocol artifacts in docs/, analysis/, and captures/. Do not introduce protocol behavior in these documents that is not already proven in the reference. When adding a new claim about wire format, cite either:

  • a .cs file path in src/MxNativeCodec/, src/MxNativeClient/, or src/MxAsbClient/, or
  • a docs/*.md spec file, or
  • a captures/0NN-frida-* directory or analysis/frida/*.tsv row.

This folder is documentation, not code. When the Rust workspace is created, the design here is the contract it must satisfy. When evidence in captures/ invalidates a design decision here, update the design first, then the code.

Reading order

  • New contributor: 00 → 30 → 10 → 40 → 20 → 50 → 60 → 70.
  • Protocol question: 40 first, then the relevant section of 10.
  • API question: 20 first, then 50.
  • Planning a milestone: 60 first, cross-reference 70 for blockers.
  • Scheduling concurrent work: dependencies.md for the per-phase parallelism map.
  • Driving M2M6 autonomously via /loop: prompt.md (and the followups.md triage log it maintains).