Yeelight Web Controller

A Python REST bridge that exposes Yeelight LAN-control bulbs through the same wire contract as a matter_webcontrol v0.25 logical bridge. A Matter server can register this service and federate Yeelight bulbs alongside its native Matter devices — no embedded scripts, no exec().

• REST — control bulbs by IP-derived ID, get / set Matter-style level (0-254) and mireds (153-500)
• Federation-ready — /api/devices and /api/metadata (api_version "2") match LogicalBridgeClient
• Discovery resilient — TCP probe fallback when SSDP multicast is blocked or bulbs stop broadcasting

Quick start

pip install yeelight-web-controller   # or: pip install -e .

# Generate an API key (used by all clients via X-API-Key header)
export YEELIGHT_SRV_KEY=$(openssl rand -hex 32)

# Start the server (auto-probe LAN /24 if SSDP returns nothing)
yeelight-srv --host 0.0.0.0 --port 9800 --auto-probe

# In another terminal — talk to it
curl -H "X-API-Key: $YEELIGHT_SRV_KEY" http://127.0.0.1:9800/api/devices

Requires Python 3.12+. Bulbs must have LAN Control enabled in the Yeelight Classic app.

How it works

┌─────────────────────┐                ┌──────────────────────┐
│  matter-srv         │                │  REST clients        │
│  (federation peer)  │                │  curl / app          │
└──────────┬──────────┘                └──────────┬───────────┘
           │ X-API-Key                            │ X-API-Key
           ▼                                      ▼
        ┌────────────────────────────────────────────────┐
        │  yeelight-srv (FastAPI)                        │
        │  ┌─────────────┐    ┌────────────────────┐     │
        │  │ SSDP cache  │    │ TCP/55443 probe    │     │
        │  └──────┬──────┘    └──────────┬─────────┘     │
        └─────────┼──────────────────────┼───────────────┘
                  ▼                      ▼
             yeelight bulbs         /24 subnet scan
              (port 55443)              (fallback)

• Bulbs are identified by capabilities.id from SSDP, or yeelight_<ip> when SSDP is unavailable. Both forms are stable across server restarts via cache.json.
• /api/devices and /api/metadata mirror the schema that matter_webcontrol's LogicalBridgeClient consumes (states.{on_off, brightness_raw, color_temp_mireds}, names: list[str], bridge.api_version: "2").
• Authentication is a single X-API-Key header. Same key used by federation peers when they register this server via /api/bridge?…&api_key=… on the matter side.

CLI options

REST API

All endpoints require X-API-Key: $YEELIGHT_SRV_KEY (when --api-key is set).

Devices are addressed by their id field (the SSDP capabilities.id, or yeelight_<ip> if seeded without SSDP). Aliases set via /api/name are display-only and not accepted as IDs.

Error mapping: 404 (device unknown), 400 (bad parameters), 401 (auth), 500 (other).

Read

Control

# 80 % warm white on a bulb
curl -H "X-API-Key: $YEELIGHT_SRV_KEY" \
  -X POST -H "Content-Type: application/json" \
  -d '{"id":"yeelight_192.168.1.7","brightness":0.8,"temperature":2700}' \
  http://127.0.0.1:9800/api/set

/api/set brightness < 0.01 activates Yeelight Moonlight where the bulb supports it.

Management

Federation with matter_webcontrol

Pair this server with a running matter-srv so Yeelight bulbs appear alongside native Matter devices:

# On the Yeelight bridge host (e.g. 10.0.0.20)
export YEELIGHT_SRV_KEY=keyY
yeelight-srv --host 0.0.0.0 --port 9800 --auto-probe

# On the matter-srv host — register this bridge as a logical peer
curl -H "X-API-Key: $MATTER_SRV_KEY" \
  "http://127.0.0.1:8080/api/bridge?ip=10.0.0.20&port=9800&api_key=keyY"

# matter-srv now exposes the Yeelight bulbs through its own endpoints:
curl -H "X-API-Key: $MATTER_SRV_KEY" http://127.0.0.1:8080/api/lights

matter-srv's LogicalBridgeClient calls /api/devices, /api/level, /api/mired, and /api/set directly over plain HTTP — no script execution, no events blobs.

Tests

The test suite drives a real bulb. Skipped by default unless an IP is provided.

pip install -e '.[test]'

export YEELIGHT_TEST_IP=192.168.1.7         # required
export YEELIGHT_TEST_ID=0x000000002ce4355f  # optional; auto-discovered if unset
export YEELIGHT_TEST_KEY=optional-secret    # optional; used by the live-server auth test

pytest -v

Coverage: /api/devices, metadata v2 schema, level (set / get / clamp), mireds (set / get / clamp), /api/set float brightness, alias add / remove, X-API-Key auth, plus an end-to-end test that mirrors the HTTP calls LogicalBridgeClient issues.

Known issues

• SSDP discovery returns empty for long-running bulbs. Yeelight bulbs only emit SSDP NOTIFY frames for a short window after power-on. After that discover_bulbs() returns [] even though TCP/55443 still works. Use --auto-probe, --seed-ip, or /api/probe to bypass SSDP.
• Bulbs occasionally drop off the LAN (~every 2 weeks). Symptom: the bulb stops answering on TCP/55443 and ignores commands. The only known recovery is a hardware power-cycle (cut mains for ~10 s, then restore). The Yeelight LAN protocol does not expose a reboot / reset command, so this cannot be triggered from the web interface — recovery requires either a smart plug upstream of the bulb or someone flipping the wall switch.
• One subnet per host. --auto-probe and /api/probe (without subnet=) scan only the /24 of each local interface. Multi-VLAN setups should pass --probe-subnet explicitly per network.

Limitations

• Only color-temperature and dimmable LAN-control Yeelight bulbs are tested. RGB-only models are not exercised by the current control mappings.
• The Yeelight LAN protocol is unauthenticated on the wire — --api-key only gates the REST front, not the bulb-side TCP. Anyone on the same L2 segment as a bulb can still control it directly on port 55443.