A device reporting a `live` port streams its camera to the browser's own
RTCPeerConnection. The flows socket carries the signalling as text, so it
crosses the portal: `live` messages on a person's socket, `signal` on a
device's (start, sdp, candidate, bye, busy). The server routes by session,
holds a device to two viewers, ends a session when either socket closes or
no answer comes within 10 s, and gives each socket an outbox of its own
that ends a session rather than drop a message. TURN credentials are
minted per session in coturn's REST scheme (STUN_URLS, TURN_URLS,
TURN_SECRET), the viewer's with the device's offer; GET /devices/{id}/ice
hands them out too. The tunnel keeps a stream's early frames instead of
dropping them past eight and forgets them when the stream or link goes.
A media tile on a device's camera, and the Devices tab's preview, play
live when tapped, pause frames meanwhile, and fall back to frames with a
short note on busy, failure or no picture within 10 s. coturn is an
optional compose service behind the `turn` profile.
- Volatile frames are held in memory with a byte-bounded queue instead of
the /dev/shm ring scanned on every put; workers keep writing to the
directory, which is trimmed on a timer. A volatile upload no longer spools
to disk. ARTIFACT_VOLATILE_BYTES=0 turns the ring off.
- A device sends camera frames as binary messages on its socket, held and
published in one step and credited to its device node; refused frames are
logged and dropped. Its snapshot carries demand and the uplink (binary, or
http through the portal).
- One demand registry for every socket's wanted media, the tunnel's
included, plus what running flows read, mapped onto on-demand ports and
published as device_demand; at most 8 media names per socket.
- Per-message deflate off in serve and dev; a device may fetch the last 8
digests of a message; published dashboards cached per store revision; a
revoked device socket is closed with 1008.
- Media tiles want bytes only while on screen; the Devices tab previews a
wired camera; the device node warns when a flow reads an on-demand port.
- POST /devices/pair answers a 2-character `check`, listed by /devices/pending
and shown beside each waiting entry; five codes a minute per address, and at
50 waiting the oldest gives way instead of a 429
- portal-minted device tokens are asked for with the device's nonce (`pnc`) and
held against it, so unpair and delete revoke them; one without `pnc` stands
only while the nonce is 0
- a device credential acts as the device (`device_principal`), not as the
approving superuser, so deleting that account unpairs nothing
- the report is validated port by port: unknown enum values read as `unknown`,
unreadable ports and sections are left out and logged, `config` may name an
entry of `config_schemas`; 422 only for no schema 1 or no object
- devices.json is parsed once per change (cached by stat), delete drops the
report and keeps the nonce, a busy recheck runs in the background
- scope and io only from enabled flows (start/stop tells the devices), a port
bound twice gives one io row
- the Devices tab's saves cancel and hold back device refetches until settled
A device reports its board, screen, camera and ports from its own
credential (16 KB, schema 1, replacing the last report), and the flows
are validated against it again. The node panel turns a reported port's
config schema into a form, a reported screen is a canvas preset and a
touch screen's first report turns Touch friendly on. An offline device
node is degraded: amber on the canvas, a warning on Home, never a fault.
- flow/nodes/device.py: `device` node with params `device` and `config`;
provides the device's `in` ports, requires its `out` ports without
waking anything, never run (Node.passive), down "Offline" from presence
- DeviceDef.io and DevicePort go; GET /devices/{id} computes `io` and
`bindings` from the device nodes of published flows, in a fixed order,
cached by FlowStore.revision; the credential's scope comes from them
- issues `unknown_device` and `device_port` (wired twice; against a report
the wrong direction or dtype, or unlisted as advisory), rechecked when a
device is created or deleted; ValidationIssue.advisory is a field
- a device publishing on a bound port is credited to its node by the
server; the panel endpoint kind is gone from `_endpoints` and the canvas
- a rebuild that moves a device's bindings sends `dashboard_changed` with
an empty name, which the firmware refetches on
- startup moves each device's `io` rows into device nodes in the flows
declaring their messages, draft and published, one commit; rows no
flow declares are logged and left out
- frontend: Device node settings (device, Publishes, Follows, a port
picker from a report), palette shortcuts per reported port, DeviceDetail
lists bindings with "Use in flow" in place of the I/O editor
- docs: devices, flow editor, node types, issues, API
- flow/devices.py: DeviceDef in FLOWS_DIR/_devices/<id>.json, committed under
the flow store's write lock, 409 on a stale version; nonces in DEVICES_FILE
outside git; in-memory presence announced as device_status
- api/routes/devices.py: CRUD, pairing with an optional {name, board,
firmware}, a pending list adopted without a code from the LAN only, unpair;
/panels/pair, /panels/pair/{code} and GET /panels/{id} kept as aliases,
PUT /panels/ gone
- _device_may replaces _panel_may, JWT claims unchanged
- panels.json moves into devices once at startup, then .migrated
- MCP list_devices, get_device; search category device
- Devices tab (list, detail with presence, pairing, ordered dashboards,
touch, I/O), PanelsDialog removed, serialised optimistic saves
Melvin Strobl