mikkeli
b55ccba268
What crosses between svc-gw and the app: hello, heartbeats both ways, state snapshots of envelopes with mock flagged per message, and commands carrying an idempotency key. TTS utterances are left for when a TTS exists. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz
45 lines
1.5 KiB
Markdown
45 lines
1.5 KiB
Markdown
---
|
|
type: plan
|
|
status: active
|
|
updated: 2026-10-09
|
|
---
|
|
# Initial plan
|
|
|
|
## What is defined
|
|
|
|
The envelope, the topic namespace, and the standard OBD-II signals — the ones
|
|
whose names, units and ranges are fixed by the standard rather than by the car.
|
|
|
|
## What is not
|
|
|
|
**Z27AG-specific signals.** They do not exist until Phase 2 identifies them from
|
|
observed traffic. They arrive as DBC entries plus registry rows with
|
|
`source: "z27ag"`, one at a time as each is confirmed.
|
|
|
|
**Composite payload shapes.** `gnss/fix`, `nav/guidance`, `nav/route` and
|
|
`system/<service>` have their fields named in `topics.json` but no JSON Schema
|
|
yet. They get one when a publisher exists to constrain.
|
|
|
|
**The app ↔ `svc-gw` boundary protocol** is at v0 in [BOUNDARY.md](../../BOUNDARY.md):
|
|
heartbeat both ways, idempotency key on every command, mock flagged per message.
|
|
Still missing from it: the TTS utterance shape (id, chunk sequence, terminator,
|
|
expiry), defined when a TTS exists to send one.
|
|
|
|
## Order
|
|
|
|
1. Schema validation available to all three languages — the Rust services, the
|
|
Python fixtures and the Dart client must reject a malformed message
|
|
identically, or the contract is decorative.
|
|
2. `gnss/fix` schema, driven by what `tool-mock` replays.
|
|
3. Z27AG signals, as Phase 2 confirms them.
|
|
|
|
## Consumers
|
|
|
|
| Repo | Reads |
|
|
|---|---|
|
|
| `svc-core` | signals, envelope, DBC |
|
|
| `svc-gw` | topics, envelope |
|
|
| `svc-nav` | topics, envelope |
|
|
| `app-flutter` | topics, envelope, signals (for display units) |
|
|
| `tool-mock` | all of it — fixtures publish the real schema |
|