punktfunk/docs-site/content/docs/automation.md

title, description

title	description
Events & hooks	React to what the host does — lifecycle events over SSE, hook commands and webhooks, per-app prep/undo — for notifications, DND toggles, Home Assistant, and more.

The host emits a lifecycle event for the things you'd want to react to: a client connects or disconnects, a stream starts or stops, a pairing request arrives, a virtual display is created, the library changes, the host starts or shuts down. Two ways to consume them:

• Hooks — zero-code: entries in ~/.config/punktfunk/hooks.json run a command or POST a webhook when a matching event fires. This covers the common automation: Do-Not-Disturb during a stream, a phone notification on a pairing request, pausing downloads while playing.
• The event stream — code: GET /api/v1/events on the management API is a standard Server-Sent Events stream of the same events, for scripts and integrations that want to decide things (e.g. auto-approve pairing from a known subnet by calling the approve endpoint).

Hooks observe — they can never veto or delay a connection, a stream, or a pairing decision, and nothing you configure here runs anywhere near the streaming path.

The events

Kind	Fires when	Carries
client.connected / client.disconnected	a client session is admitted / goes away	device name, cert fingerprint, plane (native/gamestream); disconnect adds reason: quit (user stop), timeout (vanished), error
session.started / session.ended	an A/V session registers / ends	session id, client label, mode (3840x2160@120), HDR
stream.started / stream.stopped	video actually starts / stops	mode, HDR, client name, launched app id/title (when one was requested), plane
pairing.pending	an unpaired device knocks (once per device, not per retry)	device name, fingerprint, plane
pairing.completed / pairing.denied	a pairing is approved+stored / denied	device name, fingerprint, plane
display.created / display.released	a virtual display is minted / kept displays are released	backend + mode / count
library.changed	the game library is mutated	source: manual, or the provider id that reconciled (PUT /api/v1/library/provider/{p})
host.started / host.stopping	the serve planes come up / wind down	version, whether GameStream is enabled

Every event is a small JSON document with a monotonic seq, a ts_ms timestamp, a schema version (additive-only — fields get added, never renamed), and the fields above. Example:

{ "seq": 42, "ts_ms": 1784227449526, "schema": 1,
  "kind": "stream.started",
  "stream": { "mode": "2560x1440@120", "hdr": true,
              "client": "Living Room TV", "app": "steam:570", "plane": "native" } }

Hooks: hooks.json

Create ~/.config/punktfunk/hooks.json (Windows: %ProgramData%\punktfunk\hooks.json), or PUT the same document to /api/v1/hooks from a script — changes apply immediately, no restart:

{
  "hooks": [
    { "on": "stream.started",  "run": "~/.config/punktfunk/scripts/on-stream.sh" },
    { "on": "stream.stopped",  "run": "~/.config/punktfunk/scripts/off-stream.sh" },
    { "on": "client.connected", "filter": { "client": "Living Room TV" },
      "run": "kscreen-doctor output.HDMI-A-1.mode.3840x2160@60" },
    { "on": "pairing.pending",
      "webhook": "https://ha.local/api/webhook/punktfunk",
      "hmac_secret_file": "/home/me/.config/punktfunk/webhook-secret" }
  ]
}

Each entry:

Field	Meaning
on	Which events fire it: an exact kind (stream.started) or a domain.* prefix (pairing.*).
run	A shell command (sh -c on Linux). Gets the event JSON on stdin and flat PF_EVENT_* env vars.
webhook	A URL the event JSON is POSTed to. TLS-verified, redirects are never followed, no punktfunk credentials attached.
filter	Optional exact-match constraints: client (device name), fingerprint, plane (native/gamestream), app. All present fields must match.
timeout_s	Command timeout (default 30, max 600) — on expiry the whole process group is killed.
debounce_ms	Minimum interval between firings of this hook (0 = every event).
hmac_secret_file	File with a secret; the webhook gains X-Punktfunk-Signature: sha256=<hex HMAC-SHA256 of the body> so your receiver can authenticate the host.

A run command's shell one-liner vocabulary — the event flattened to env, values sanitized:

#!/bin/sh
# PF_EVENT_KIND=stream.started   PF_EVENT_SEQ=42
# PF_EVENT_STREAM_MODE=2560x1440@120   PF_EVENT_STREAM_HDR=true
# PF_EVENT_STREAM_CLIENT='Living Room TV'   PF_EVENT_STREAM_APP=steam:570
# PF_EVENT_STREAM_PLANE=native   PF_EVENT_JSON='{…the whole event…}'
[ "$PF_EVENT_KIND" = stream.started ] && makoctl mode -a do-not-disturb

Richer payloads (and the full document) are on stdin — jq away. On a Windows host running as the service, the command runs in your interactive session (never as SYSTEM); that path can't carry per-process env or stdin, so the event JSON's path is appended as the command's last argument instead.

Verify a signed webhook (Python):

import hmac, hashlib
expected = "sha256=" + hmac.new(secret, body, hashlib.sha256).hexdigest()
ok = hmac.compare_digest(request.headers["X-Punktfunk-Signature"], expected)

Rules of the road: hooks are fire-and-forget and bounded — at most 8 in flight (extra firings are dropped with a log line, never queued), and a command that outlives its timeout is killed. Because hook commands run as the host user, hooks.json is operator-privileged config; a hook script must be owned by you (or root) and not group/world-writable, or the host refuses to run it — loudly, in the log.

The two simplest cases also exist as plain host.env settings, no hooks.json needed: PUNKTFUNK_ON_CONNECT_CMD and PUNKTFUNK_ON_DISCONNECT_CMD.

Per-app prep/undo

For per-title setup (HDR toggle, MangoHud, a VRR tweak), attach prep steps to a GameStream apps.json entry or a custom library entry — each do runs before the title launches (synchronously — the launch waits), each undo runs at session end in reverse order, best-effort, even if the session crashed:

{ "id": 2, "title": "Steam", "compositor": "gamescope", "cmd": "steam -gamepadui",
  "prep": [
    { "do": "~/bin/hdr on",  "undo": "~/bin/hdr off" },
    { "do": "pactl set-default-sink game_sink", "undo": "pactl set-default-sink desk_sink" }
  ] }

A do that fails logs, keeps going, and its own undo is skipped (it never took effect).

The event stream (GET /api/v1/events)

For code, subscribe to the SSE stream on the management API (loopback + bearer token — the same credentials as the rest of the admin surface):

curl -Nk -H "Authorization: Bearer $(cat ~/.config/punktfunk/mgmt-token)" \
  "https://127.0.0.1:47990/api/v1/events?kinds=pairing.*,stream.*"

• Frames carry id: (the event's seq), event: (the kind), data: (the event JSON).
• Reconnect with the standard Last-Event-ID header (or ?since=<seq>) and the host replays what you missed from its in-memory ring (~1024 events); if you fell off the ring you get one event: dropped frame first — resync from the REST snapshots (/status, /clients, …).
• ?kinds= filters server-side: exact kinds or domain.* prefixes, comma-separated.

Scripts, plugins, and the runner

For anything beyond a curl one-liner there is @punktfunk/host — the TypeScript SDK (sdk/ in the repo): typed events with automatic reconnect/resume, the REST surface, and a plugin convention (punktfunk-plugin-*). Its runner (punktfunk-scripting) supervises a directory of scripts and installed plugins as one service: crash-restarts with backoff, and a systemctl stop that interrupts plugins structurally so their cleanup runs. See the SDK README for the five-line quickstart and unit templates.

The canonical "decide, don't just observe" pattern — approve pairing from your phone: watch pairing.pending, send yourself a notification, and call POST /api/v1/native/pending/{id}/approve when you tap yes. The full API is documented at /api/docs on your host.