Foundation for response decoding. Adds:
* `contracts::ItemStatus` — ports `AsbContracts.cs:639-722`. Wire
layout matches `WriteToStream` exactly: Item (ItemIdentity binary)
→ Status (AsbStatus binary, from F24) → ErrorCode (u16) →
ErrorCodeSpecified (u8 bool). Note this is NOT the DataMember
declaration order — the binary serialiser hand-picks Item-first.
* `encode_item_status_array` / `decode_item_status_array` — same
4-byte int32 count + per-element WriteToStream pattern as the
ItemIdentity array codec.
* `operations::collect_asbidata_payloads(tokens, field_name)` — walks
an NBFX token stream and pulls out `<{field}><ASBIData>{Bytes}
</ASBIData></{field}>` payload bytes. Returns Vec<Vec<u8>> because
some response shapes (ReadResponse) carry multiple ASBIData
payloads (Status + Values).
* `decode_register_items_response` / `decode_unregister_items_response`
— parse SOAP body NBFX tokens into typed RegisterItemsResponse /
UnregisterItemsResponse. The optional ItemCapabilities array (XML-
serialised, not binary) is recorded as a presence flag for now;
decoding the individual ItemRegistration records is a follow-up.
* `build_read_request_body(items)` — simplest unary IASBIDataV2
request, just `<ReadRequest xmlns="..."><Items><ASBIData>...
</ASBIData></Items></ReadRequest>`.
* `OperationError` — typed error for response-decode failures
(`MissingField { field }` and codec wraps).
9 new tests: ItemStatus round-trip (default + with id + with status
payload), ItemStatus array round-trip, RegisterItemsResponse
round-trip via synthetic body, ItemCapabilities presence detection,
UnregisterItemsResponse round-trip, multi-payload extraction (ReadResponse-
shape Status + Values), Read body shape correctness, MissingField
error when Status is absent.
Stubbed for next F25 iteration: Write / PublishWriteComplete /
CreateSubscription / AddMonitoredItems / DeleteMonitoredItems /
Publish builders, ReadResponse + WriteResponse decoders (need
WriteValue / RuntimeValue contract codecs), and the AsbClient
network loop.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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 M2–M6 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
.csfile path insrc/MxNativeCodec/,src/MxNativeClient/, orsrc/MxAsbClient/, or - a
docs/*.mdspec file, or - a
captures/0NN-frida-*directory oranalysis/frida/*.tsvrow.
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.mdfor the per-phase parallelism map. - Driving M2–M6 autonomously via
/loop:prompt.md(and thefollowups.mdtriage log it maintains).