Adds the public high-level entry point for the ASB transport.
Parallel to the NMX-shaped `Session` (rather than unified) because
NMX's `Session` carries CallbackExporter / callback router task /
recovery broadcast / INmxService2 mutex orchestration that has no
ASB analogue — and ASB's request/response loop over a single TCP
stream maps naturally to `Mutex<AsbClient>` that would be foreign
to NMX. Two paths converge at the consumer-facing API but stay
distinct at the orchestration layer.
Struct shape:
```rust
pub struct AsbSession { inner: Arc<AsbSessionInner> }
struct AsbSessionInner {
transport: Mutex<AsbTransport<TcpStream>>,
connect_response: ConnectResponse,
}
```
`Clone + Send + Sync` — clones share state through `Arc`, lock
serialises operations. Compile-time `assert_clone_send_sync` test
guards the contract.
API:
* `connect(endpoint, passphrase, crypto_parameters, via_uri,
connection_id)` — full bring-up (TCP + preamble + DH handshake).
* `from_transport(transport, connect_response)` — build from an
existing transport (tests, custom transports).
* `connect_response()` — surface the negotiated lifetime /
Apollo flag.
Operation methods forward to AsbClient:
* `register_items` / `unregister_items` / `read` / `write`
* `keep_alive` / `disconnect`
* `create_subscription` / `add_monitored_items` / `publish` /
`delete_monitored_items` / `delete_subscription`
* `publish_write_complete`
ClientError → mxaccess::Error mapping via
`ConnectionError::TransportFailure` (consistent with F26 step 2).
1 new test:
* `asb_session_is_clone_send_sync` — compile-time trait-bound
assertion.
Workspace: 702 tests pass.
Stubbed for next F26 iteration:
* `Stream<Item = MonitoredItemValue>` subscription handle that
internally drives a publish-loop. Today consumers loop
`publish().await` themselves.
* Recovery / reconnect policy — needs a captured ASB-side
disconnect to inform the retry strategy.
* Live-probe wire-byte reconciliation against the WCF DataContract
XML serializer's actual output.
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).