Investigation continued via examples/asb-relay.rs middleman:
captured the .NET probe's verbatim AddMonitoredItems request bytes
(695 bytes with the 3-byte NMF SizedEnvelope header). Saved at
rust/crates/mxaccess-asb/tests/fixtures/add-monitored-items-request-wire.bin
as the ground-truth shape MxDataProvider actually accepts.
New tests/add_monitored_items_request_capture.rs runs decode_envelope
over the capture and dumps every NBFX token to stderr for inspection.
Decoded trace surfaces a SECOND, deeper issue:
The F30 dynamic-dict-resolution post-pass at
envelope.rs::resolve_dict_names_in_tokens mis-maps per-session dict
ids. Decoding the captured request renders namespace-URL slots as
field-name strings:
body[1]=DefaultNamespace { value: Chars("nameField") } ← bogus
body[7]=NamespaceDeclaration { prefix: "i",
value: Chars("activeField") } ← bogus
and leaves most element names as `Static(NN)` instead of resolving
to inline names like `activeField` / `bufferedField` / `itemField`.
This blocks F34's substantive fix (rewrite
build_add_monitored_items_request_body to use DataContract
field-suffix names matching the wire). We can't validate the
rewritten builder against the captured fixture until the dict
post-pass produces the right strings.
design/followups.md F34 updated with two-prerequisite resolution
plan:
1. Fix the F30 dynamic-dict resolution so the captured request
decodes to recognisable inline names.
2. Rewrite the AddMonitoredItems / DeleteMonitoredItems builders
against the now-readable structure (DataContract field names
+ namespace prefixes for ASBIDataV2Contract / ASBContract +
nested DataContract serialization of ItemIdentity inside
`<itemField>` and Variants inside userDataField /
valueDeadbandField).
Workspace: mxaccess-asb 96 → 97 (+1 capture-driven analysis test);
default-feature clippy clean. The HMAC canonical-XML signing path
remains correct (F28 fixtures are byte-equal to .NET); only the
binary NBFX wire body needs the rewrite.
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).