lmxopcua/docs/plans/2026-07-24-driver-expansion-tracking.md

# Driver-expansion — Waves 0–2 tracking

> **Living status tracker** for the driver-expansion program (Waves 0, 1, 2). One row per
> deliverable, each pointing at its **design doc**, its **implementation plan** (once written),
> and its current **status**. The authoritative *architecture* index is the program design doc;
> this file is the authoritative *progress* index.
>
> **Program design (architecture / shared contract / build order):**
> [`2026-07-15-driver-expansion-program-design.md`](2026-07-15-driver-expansion-program-design.md)
>
> Last updated: 2026-07-24.

## Legend

| Status | Meaning |
|---|---|
| ✅ **Done** | Merged to master, tests green. |
| 🟡 **Live gate open** | Code merged; a live `/run` or hardware-gated verification still outstanding. |
| 📝 **Plan ready** | Executable implementation plan (`*-implementation.md` + `.tasks.json`) written; not yet built. |
| 📐 **Design only** | Design doc exists; **no** implementation plan yet — writing-plans is the next step. |
| ⛔ **Not started** | No design, no plan. |

**Doc types** (per the writing-plans skill): a *design* states architecture, decisions, and risks;
an *implementation plan* is the bite-sized, TDD, file-path-level task list the subagent-driven
executor runs off, with a co-located `.tasks.json` for resume. A deliverable is only buildable once
it reaches 📝.

## Summary

| Wave | Deliverable | Design | Impl. plan | Status | Effort | Fixture / hardware |
|---|---|---|---|---|---|---|
| **0** | Universal Discover-backed browser | [design](2026-07-15-universal-discovery-browser-design.md) | [plan](2026-07-15-universal-discovery-browser-implementation.md) · [tasks](2026-07-15-universal-discovery-browser-implementation.md.tasks.json) | 🟡 **Live gate open** | S–M | none (retrofits shipped drivers) |
| **1** | Modbus RTU (extend Modbus) | [design](2026-07-15-modbus-rtu-driver-design.md) | [plan](2026-07-24-modbus-rtu-driver.md) · [tasks](2026-07-24-modbus-rtu-driver.md.tasks.json) | 🟢 **Built — live gate PASSED** (11 tasks, branch `feat/modbus-rtu-driver`, pending merge) | **S (lowest)** | `pymodbus` `rtu_over_tcp` — CI-simulatable, no new infra |
| **1** | SQL poll | [design](2026-07-15-sql-poll-driver-design.md) | [plan](2026-07-24-sql-poll-driver.md) · [tasks](2026-07-24-sql-poll-driver.md.tasks.json) | 📝 **Plan ready** (22 tasks) | S–M | **existing central SQL Server** `10.100.0.35,14330` + SQLite unit |
| **2** | MTConnect Agent | [design](2026-07-15-mtconnect-driver-design.md) | [plan](2026-07-24-mtconnect-driver.md) · [tasks](2026-07-24-mtconnect-driver.md.tasks.json) | 📝 **Plan ready** (23 tasks) | S–M | Dockerized `mtconnect/cppagent` — CI-simulatable |
| **2** | MQTT / Sparkplug B | [design](2026-07-15-mqtt-sparkplug-driver-design.md) | [plan](2026-07-24-mqtt-sparkplug-driver.md) · [tasks](2026-07-24-mqtt-sparkplug-driver.md.tasks.json) | ✅ **COMPLETE** — P1 + P2 shipped, both live-gated (Tasks 0–26) | M–L | Mosquitto TLS+auth **+ C# Sparkplug edge-node simulator**, live at `10.100.0.35:8883` |

> Waves 3+ (BACnet/IP, Omron) and the deferred MELSEC are tracked in the program design doc §6/§8,
> not here. Omron CIP is the program's sole real-hardware wire gate; BACnet's broadcast/BBMD leg is
> env-gated live. Both are out of this file's scope until they're pulled forward.

---

## Executing a plan (git worktree + subagent-per-task)

Each 📝 plan is executed with the **subagent-driven-development** skill: it sets up an isolated
**git worktree** first (via `using-git-worktrees`), then dispatches a **fresh subagent per task**,
running the classification-driven review chain (`trivial` = implement only … `high-risk` =
spec-review → code-review → integration review) between tasks. The `.tasks.json` next to each plan
tracks progress and lets a later session resume.

**Paste one of these into Claude Code to build a driver:**

| Deliverable | Command |
|---|---|
| Modbus RTU (Wave 1) | `Use superpowers-extended-cc:subagent-driven-development to execute docs/plans/2026-07-24-modbus-rtu-driver.md in a new git worktree` |
| SQL poll (Wave 1) | `Use superpowers-extended-cc:subagent-driven-development to execute docs/plans/2026-07-24-sql-poll-driver.md in a new git worktree` |
| MTConnect (Wave 2) | `Use superpowers-extended-cc:subagent-driven-development to execute docs/plans/2026-07-24-mtconnect-driver.md in a new git worktree` |
| MQTT/Sparkplug (Wave 2) | `Use superpowers-extended-cc:subagent-driven-development to execute docs/plans/2026-07-24-mqtt-sparkplug-driver.md in a new git worktree` |

- **Slash-command form** (equivalent): `/superpowers-extended-cc:subagent-driven-development <plan-path>`.
- **Parallel-session / resume form** (batch execution with checkpoints, no fresh-subagent-per-task):
  `/superpowers-extended-cc:executing-plans <plan-path>` — reads the same `.tasks.json` and continues
  from the first pending task.
- **Recommended order:** Modbus RTU → SQL poll → MTConnect → MQTT/Sparkplug (lowest effort first;
  see each wave below for the gating notes). Run one plan per worktree; the four plans are
  independent, so separate worktrees may run concurrently.

---

## Wave 0 — Universal Discover-backed browser 🟡

**What it is.** One generic `DiscoveryDriverBrowser` (+ `CapturingAddressSpaceBuilder`,
`CapturedTreeBrowseSession`, `BrowserSessionService` fallback, and the
`ITagDiscovery.SupportsOnlineDiscovery` gate) that turns any driver's `ITagDiscovery.DiscoverAsync`
into an AdminUI browse tree. It is the **Wave-0 gate**: every browsable new driver depends on this
seam, and it retrofits browse to the already-shipped AbCip / TwinCAT / FOCAS drivers for near-zero
marginal cost.

- **Design:** [`2026-07-15-universal-discovery-browser-design.md`](2026-07-15-universal-discovery-browser-design.md)
- **Implementation plan:** [`2026-07-15-universal-discovery-browser-implementation.md`](2026-07-15-universal-discovery-browser-implementation.md) · [`.tasks.json`](2026-07-15-universal-discovery-browser-implementation.md.tasks.json)
- **Status: 🟡 code-complete + merged, live gate open.**
  - Merged to master — `056887d6` (*Merge feat/universal-discovery-browser — Wave-0 universal Discover-backed browser*), 2026-07-15.
  - Implementation plan: **19 / 19 tasks completed.**
  - Lit up AbCip / TwinCAT / FOCAS pickers with zero per-driver browse code.
- **Outstanding:** the full tree-render live `/run` gate is **fixture-blocked** — tracked as **Gitea #468**. Complete this before leaning on browse in Wave 2/3.

---

## Wave 1 — low-effort / high-leverage pair 📝

Both are **fully CI-simulatable with zero new hardware**; Modbus RTU needs no new infra at all, and
SQL poll reuses the always-on central SQL Server. This is the recommended next build.

### Modbus RTU — 🟢 Built, live gate PASSED (branch `feat/modbus-rtu-driver`, pending merge)
- **Design:** [`2026-07-15-modbus-rtu-driver-design.md`](2026-07-15-modbus-rtu-driver-design.md)
- **Implementation plan:** [`2026-07-24-modbus-rtu-driver.md`](2026-07-24-modbus-rtu-driver.md) · [`.tasks.json`](2026-07-24-modbus-rtu-driver.md.tasks.json) — **11 tasks** (1 trivial / 5 small / 2 standard / 3 high-risk), all complete via subagent-driven-development.
- **Scope:** extend the existing Modbus driver with a `Transport` selector (RTU CRC-16 + FC-aware
  length, no TxId) + a `rtu_over_tcp` `pymodbus` docker profile + the AdminUI selector.
  **Direct-serial transport is descoped** (user, 2026-07-15) — RTU-over-TCP via a serial→Ethernet
  gateway is the only shipped mode, so there is no serial hardware gate.
- **Fixture:** added the `rtu_over_tcp` profile (`framer=rtu`, host `:5021`, co-runs with `standard`)
  to the Modbus integration fixture. **Unknown confirmed:** pymodbus 3.13's simulator DOES honour
  `framer=rtu` on a TCP server (wire-probed a pure RTU FC03 response, no MBAP) — so the simple profile
  path was taken; **no stdlib fallback server was needed.**
- **Verification (all green):** unit suite **344/344**; full solution build 0 errors; the 2 RTU
  integration tests pass **live** against the real `framer=rtu` fixture (read HR5→5, write+readback
  HR200←4242). Per-task review chain (spec + code reviewers) + a final whole-branch review, all
  approved-to-merge.
- **Live `/run` gate — PASSED (2026-07-24, docker-dev rebuilt from this branch):**
  - AdminUI `/raw` Modbus **driver** config modal renders the new **Transport** selector (with the
    operator hint) — set to `RtuOverTcp`, saved.
  - **Device Test Connect → `OK · 23 MS`** — the probe built a `ModbusRtuOverTcpTransport` via the
    factory and spoke **FC03 over real RTU framing** to `10.100.0.35:5021`.
  - Authored raw tags HR5 (r/o) + HR200 (r/w) → **deployment `06ec1632` Sealed** (all 6 nodes acked).
  - Client.CLI on `opc.tcp://localhost:4840` (`multi-role`/`password`): **read** `ns=2;s=rtu-gate/Device1/HR5`
    → **5, Good**; **write** `ns=2;s=rtu-gate/Device1/HR200` = 4242 → readback **4242, Good**.
- **Effort:** **S — the lowest on the roadmap.** Delivered first, as recommended.

### SQL poll — 📝 Plan ready
- **Design:** [`2026-07-15-sql-poll-driver-design.md`](2026-07-15-sql-poll-driver-design.md)
- **Implementation plan:** [`2026-07-24-sql-poll-driver.md`](2026-07-24-sql-poll-driver.md) · [`.tasks.json`](2026-07-24-sql-poll-driver.md.tasks.json) — **22 tasks**. `ISqlDialect` seam in from day one; only the SQL Server dialect built in v1 (Postgres/ODBC deferred).
- **Scope:** a bespoke schema-browser driver polling a SQL table into equipment tags (SQL Server P1;
  Postgres/ODBC land in P2/P3 behind `ISqlDialect`).
- **Fixture:** SQLite unit fixture (primary) + an **env-gated integration fixture against the
  existing central SQL Server** (`10.100.0.35,14330`) with a seeded `SqlPollFixture` DB. The
  blackhole/timeout live-gate pauses a **dedicated** `mssql` container — **never** the shared
  central SQL Server (it hosts `ConfigDb`).
- **Effort:** S–M.

---

## Wave 2 — strategic telemetry / UNS pair 📝

Both CI-simulatable on the shared docker host, no hardware.

### MTConnect Agent — 📝 Plan ready
- **Design:** [`2026-07-15-mtconnect-driver-design.md`](2026-07-15-mtconnect-driver-design.md)
- **Implementation plan:** [`2026-07-24-mtconnect-driver.md`](2026-07-24-mtconnect-driver.md) · [`.tasks.json`](2026-07-24-mtconnect-driver.md.tasks.json) — **23 tasks**. Task 0 is the TrakHound-vs-hand-rolled client decision; browse-picker live-verify is gated on Wave-0 #468.
- **Scope:** P1 Agent MVP (`IDriver`+`ITagDiscovery`+`IReadable`+`ISubscribable`+probe+rediscover),
  browse **free via the Wave-0 universal browser** (`SupportsOnlineDiscovery=true`, no browser code),
  typed editor, `UNAVAILABLE→BadNoCommunication` mapping, ring-buffer re-baseline paging.
- **Fixture:** canned XML unit fixtures (bulk of coverage) + a dockerized `mtconnect/cppagent`
  integration fixture (env-gated). Depends on Wave 0's browse seam being live-verified (#468).
- **Effort:** S–M (≈1–1.5 wk with TrakHound, ≈2.5–3 wk hand-rolled).

### MQTT / Sparkplug B — ✅ **COMPLETE** (P1 + P2, both live-gated)
- **Design:** [`2026-07-15-mqtt-sparkplug-driver-design.md`](2026-07-15-mqtt-sparkplug-driver-design.md)
- **Implementation plan:** [`2026-07-24-mqtt-sparkplug-driver.md`](2026-07-24-mqtt-sparkplug-driver.md) · [`.tasks.json`](2026-07-24-mqtt-sparkplug-driver.md.tasks.json) — **27 tasks, all done** (P1 plain MQTT = Tasks 0–14; P2 Sparkplug B = Tasks 15–26).
- **Scope delivered:** P1 plain MQTT (MQTTnet-5 connect/TLS/auth + hand-rolled reconnect, subscribe→
  `OnDataChange`, retained last-value read, `#`-observation browser); P2 Sparkplug B ingest
  (vendored Tahu proto + `Grpc.Tools` codegen, birth/alias/seq-gap/rebirth state machine,
  death→STALE, birth-driven browse tree, scoped Request-rebirth NCMD, typed tag editor).
  **Write-through (`IWritable`) is deferred to P3** — every MQTT node materializes read-only.
- **Fixture:** Mosquitto TLS+auth broker + JSON publisher sidecar, **live** at `10.100.0.35:8883`
  (`:1883` plaintext-but-authenticated); stack `/opt/otopcua-mqtt`, compose in
  `tests/Drivers/…​.Driver.Mqtt.IntegrationTests/Docker/`. Env-gated live suite
  (`MQTT_FIXTURE_ENDPOINT`, see `infra/README.md` §3). The **project-owned C# Sparkplug edge-node
  simulator** (`--profile sparkplug`, group `OtOpcUaSim`, nodes `EdgeA`/`EdgeB`, `EdgeA` device
  `Filler1`) shipped with P2 and answers rebirth NCMDs.
- **P2 status (2026-07-25):** Tasks 15–26 complete. **Offline 1528 passed / 0 failed**
  (581 driver · 809 AdminUI · 138 Core.Abstractions); **live 15/15** against the broker + simulator.
- **P1 live gate found two AdminUI authoring gaps** (the gate's whole point — both invisible to green
  unit tests, because AdminUI has no bUnit and nothing tied these hand-maintained lists to
  `DriverTypeNames`):
  1. **FIXED —** `RawDriverTypeDialog`'s option array never got an MQTT row, so **no operator could
     create an MQTT driver at all**. Fixed, plus a reflection parity guard
     (`RawDriverTypeDialogParityTests`) that fails for *any* future `DriverTypeNames` entry
     missing from the picker.
  2. **FIXED —** `MqttDriverForm` / `MqttDeviceForm` did not exist, so the broker connection was
     unauthorable from the AdminUI. Both shipped after the P1 gate.
- **P2 live gate found a third one, of the same family — FIXED:** `MqttDriverForm` still carried its
  P1 Sparkplug **placeholder**. Switching Mode to `SparkplugB` rendered a *"not available yet"* notice
  and **no Group ID field** — so once Sparkplug ingest shipped there was still **no way to author a
  Sparkplug driver from the AdminUI**, and `Sparkplug.GroupId` is the driver's entire subscription
  filter (`spBv1.0/{GroupId}/#`): blank ⇒ connected, `Healthy`, ingesting nothing. Fixed (all five
  Sparkplug keys, merge-not-replace on save, group-id segment validation) + 8 falsifiable
  `MqttDriverFormModelTests` cases. **Three gates, three instances of the same defect class: a
  hand-maintained AdminUI surface left behind by a driver-side feature.**
- **P2 live gate — two open UI gaps, documented not fixed** (see `docs/drivers/Mqtt.md` §Known gaps):
  - **A completely empty browse tree cannot arm a rebirth.** The scope comes from a tree click, so on
    a plant that has not birthed since the window opened `Request rebirth…` stays disabled — the very
    case the affordance exists for. `MqttBrowseSession.ResolveRebirthTargets` already accepts a bare
    `{group}/{edgeNode}` ("the prime rebirth target"); only a UI path to enter one is missing.
    Mitigation shipped: a **Refresh** button on the browse tree (it re-reads the same session, which
    previously rendered exactly once at open and never again).
- **P2 live gate also found a PRE-EXISTING, cross-driver AdminUI defect — FIXED:** every node label in
  the shared `DriverBrowseTree` was an `<a href="#">`. In a Blazor Web App, `blazor.web.js`'s
  enhanced-navigation click interceptor resolves a bare `#` against `<base href="/">`, so **clicking
  any browse-tree node label navigated the whole AdminUI to `/`**, tore down the circuit and destroyed
  the hosting modal — losing the browse session and the tag selection. `@onclick:preventDefault` does
  not help: it suppresses the browser's default action, not Blazor's own interceptor. The labels are
  now `<button type="button">`. It dates to the component's introduction (2026-05-28) and affects
  **every** driver's picker; it only surfaced now because Sparkplug's Request-rebirth is the first
  feature that requires clicking a *label* rather than the ▶ toggle (always a `<button>`, always fine).
  - **A metric name containing `/` cannot be browse-committed.** The derived raw **tag Name** is a
    RawPath segment and may not contain `/`, while `metricName` legitimately may — so the
    spec-mandatory `Node Control/Rebirth` is refused at commit (`Row N: Name must not contain '/'`).
    The refusal is loud and all-or-nothing, never a silently mis-bound tag, and **Manual entry** is
    the working path (the Sparkplug tag editor accepts a slashed metric name). Fixing it needs a
    name-sanitisation policy with a collision answer, so it was recorded rather than guessed at.
  - `_canRebirth` is captured at browse-open, so a reaped session still draws the button.
  - The tag editor injects the Plain-only `payloadFormat` key into a Sparkplug blob — cosmetic; the
    factory routes on the Sparkplug tuple and ignores it.
- **Rediscovery is inert in v3 (platform gap, not MQTT's).** The Sparkplug driver raises
  `OnRediscoveryNeeded` on a changed birth metric-set, but **nothing subscribes to it** and
  `DriverHostActor.HandleDiscoveredNodes` hard-returns. A DBIRTH introducing a metric does **not**
  change the OPC UA tree — redeploy. Driver-side behaviour is log-observable only.
- **Redundant-pair hazard (documented, not a code change):** both nodes of a pair run the driver, so a
  **fixed `clientId` makes them evict each other forever** — the broker logs
  `already connected, closing old connection` and both nodes reconnect every ~2 s while still
  reporting `Healthy`. Unset (the default) is correct. `MqttDriverForm` warns inline the moment a
  value is typed.
- **Effort:** M–L, delivered. The MQTTnet-5/net10 + central-pinning risk is **retired** (Task 0's
  spike held through both phases); Sparkplug state-machine correctness was carried by golden-payload
  vectors + the live simulator.

---

## Next actions

1. **Close the Wave-0 live gate** (Gitea #468) — unblocks browse verification for MTConnect/BACnet.
2. **Build Wave 1** — Modbus RTU first (lowest effort, no new infra), then SQL poll. Both plans are
   📝 ready; run the command from the [Executing a plan](#executing-a-plan-git-worktree--subagent-per-task)
   table (subagent-driven-development in a git worktree).
3. **Build Wave 2** — MTConnect's browse leg wants #468 closed first. **MQTT / Sparkplug B is
   COMPLETE** (P1 + P2, both live-gated); its only remaining work is optional — P3 write-through
   (`IWritable`: NCMD/DCMD + plain publish) and the two browse-UI gaps recorded above.

Update this file's Summary table and per-wave status whenever a deliverable changes state.