DeviceDiscoveryModule¶

Discovers other projectMM nodes on the local network via UDP broadcast and lists them in the UI.

What it does¶

On startup the module binds a UDP socket on port 23452 and immediately broadcasts its own presence. It continues broadcasting every broadcast_interval milliseconds. Incoming packets from other projectMM nodes are parsed and displayed as device_N controls — up to 8 devices.

Each entry shows: MM-70BC @ 192.168.8.156 (v1.3.0)

Self-packets (same device_name as the local node) are silently filtered out.

Protocol¶

Field	Value
Transport	UDP broadcast to `255.255.255.255`
Port	23452
Packet format	`{"device":"MM-70BC","version":"1.3.0"}`
Sender IP	Read from the UDP source address — not included in the payload

Parent¶

NetworkModule — wire via setInput("network"). The parent's deviceName() is used as the source identifier in outgoing packets.

Controls¶

Key	Type	Description
`broadcast_interval`	range (1000–30000 ms)	How often to broadcast presence
`status`	display	`"N device(s) found"`
`device_1` … `device_8`	display	Each discovered peer: `name @ ip (version)`

Health report¶

devices=2 port=23452

Platform support¶

Platform	Status
PC (macOS/Linux)	✅ POSIX non-blocking UDP socket
ESP32 (Arduino)	✅ `WiFiUDP` pool in `pal::_detail`
ESP-IDF (bare)	⬜ Stubs — discovery inactive; no packets sent or received

Setup example¶

{
  "id": "discovery1",
  "type": "DeviceDiscoveryModule",
  "parent_id": "network1",
  "inputs": { "network": "network1" }
}

Or via REST:

curl -X POST http://localhost:80/api/modules \
  -H 'Content-Type: application/json' \
  -d '{"id":"discovery1","type":"DeviceDiscoveryModule","parent_id":"network1","inputs":{"network":"network1"}}'

Test coverage¶

Unit tests live in tests/test_network.cpp (DeviceDiscovery section).

→ Network and WiFi — lifecycle, category, control registration, healthReport format, setInput wiring, broadcast_interval state round-trip, getControlValues.

Live: test0 — Infrastructure Modules — DeviceDiscoveryModule present (or created) as a child of NetworkModule on every device before each live test run.

Live: test4 — Device Discovery — waits up to 10 s for devices >= 1 in healthReport, confirming real UDP packets are exchanged between peers.

Implementation¶

src/modules/system/DeviceDiscovery.h
PAL UDP functions: pal::udp_bind, pal::udp_broadcast, pal::udp_recv, pal::udp_close — see src/pal/Pal.h
Tests: tests/test_network.cpp (DeviceDiscovery section)