MQTT, webhooks, notifications

Fregata uses upstream Frigate’s notification model unchanged. The short version: MQTT for live state, the HTTP API for snapshots and clips, webhooks if you want a synchronous out-of-band push. This page covers the macOS-specific bits and points at the Frigate docs for the rest.

The data plane

When something happens on a camera, Fregata emits:

An MQTT message on a per-camera, per-class topic.
A new row in the SQLite events table.
(If snapshots.enabled: true) a JPEG to ~/Fregata/media/clips/<camera>-<event-id>.jpg.
(If record.enabled: true) the event clip to ~/Fregata/media/clips/<camera>-<event-id>.mp4, once the event ends.

The HTTP API at http://localhost:8971/api/... exposes all of those to the rest of your stack — see the Frigate HTTP API reference.

MQTT setup

The minimal config block in ~/Fregata/config/config.yml:

mqtt:
  enabled: true
  host: 10.0.1.42
  port: 1883
  user: fregata
  password: !env_var FREGATA_MQTT_PASSWORD
  topic_prefix: frigate
  client_id: fregata
  stats_interval: 60

Fregata sets topic_prefix: frigate by default for compatibility with existing dashboards and the HA integration. Override it if you want — but if you do, remember to set the same topic_prefix in the HA integration config.

The topics you’ll typically care about:

Topic	Payload	When
`frigate/events`	JSON event object	New event, in-progress update, end
`frigate/<camera>/<class>`	`ON` / `OFF`	Class enters or leaves the frame
`frigate/<camera>/<class>/snapshot`	JPEG bytes	New event snapshot
`frigate/<camera>/motion`	`ON` / `OFF`	Motion start / stop
`frigate/stats`	JSON system stats	Every `stats_interval` seconds

For the full topic catalogue see the Frigate MQTT reference.

Webhooks (a common pattern, not built-in)

Fregata doesn’t ship a “webhooks” config block per se — the cleanest way to get HTTP push notifications is to subscribe to MQTT events from a tiny external script. A 30-line shell + mosquitto_sub script is plenty:

#!/usr/bin/env bash
mosquitto_sub -h 10.0.1.42 -t 'frigate/events' | while read -r line; do
  curl -X POST -H 'Content-Type: application/json' \
       -d "$line" \
       https://hooks.example.com/fregata
done

Run that from a launchctl-managed agent on the same Mac (or a different machine) and you’ve got a webhook bridge. If this becomes an ongoing project, you’ll probably outgrow shell — but it’s a fine starting point.

Push notifications to your phone

The two cleanest paths:

Through Home Assistant. The HA mobile app supports rich push with images via notify.mobile_app_*. The Home Assistant guide shows the automation template.
Directly via Pushover, Telegram, or ntfy. Same MQTT-bridge pattern as above. The notification body can include the snapshot URL (/api/events/<id>/snapshot.jpg) so phones render the image inline.

There’s no first-party Fregata mobile app and no plans for one. The NVR is the boring, well-understood part; the phone delivery is best left to whichever of the dozens of solid push services you already use.

A note on macOS power management

Fregata is a regular foreground app. If your Mac sleeps, MQTT publishing stops because the Python process is paused. Two options:

Keep it awake. A Mac mini dedicated to Fregata should have Energy Saver set to “Prevent automatic sleeping when the display is off” and “Wake for network access” — the relevant settings are in System Settings → Energy Saver (or Battery on laptops).
Live with it. A laptop that sleeps when its lid closes is going to miss events. That’s not a Fregata behaviour, it’s the OS. If you need 24/7 detection, run on a desktop Mac.