blob: b8405b5c9d2a93953df56061e99f5abf648407d2 [file] [log] [blame]
// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
using zx;
using SessionId = uint64;
/// SessionInfoDelta holds a description of a given session. The first
/// time a client receives this, it is a state of the world. On successive
/// receipts of this table, only the changed fields will be present (this
/// property is not recursive; top-level fields if set are snapshots).
table SessionInfoDelta {
/// The domain on which the session takes place. A domain identifies a set of
/// mutually compatable media targets and sessions; sessions on a domain may
/// be played back on targets of the same domain.
1: Domain domain;
/// Whether the entry point for the media into our device network is the local
/// machine; this should be true if this is the device streaming from
/// a music service, but false if this machine is just receiving an audio stream
/// to act as a speaker.
2: bool is_local;
/// If this is set, the playback is taking place local to the device.
/// Playing on the device speaker is local, playing on a remote speaker
/// is not. This is only set when the session is playing back; a paused
/// session is not active.
3: bool is_locally_active;
4: PlayerStatus player_status;
5: metadata;
6: vector<MediaImage> media_images;
7: PlayerCapabilities player_capabilities;
/// A protocol for clients to control sessions and view their status.
protocol SessionControl {
/// Plays media.
/// Pauses playback and retains position in media
/// Stops playback. The session should close.
/// Seeks to a specific position in media. Implementations are free to
/// enter an error state if the position is out of bounds. `position`
/// is an offset from the beginning of the media.
Seek(zx.duration position);
/// Skips forward in media by the player's default skip amount.
/// Skips in reverse in media by the player's default skip amount.
/// Changes media to the next item (e.g. next song in playlist).
/// Changes media to the previous item.
/// Sets the playback rate of the media. This will not change the
/// playback mode.
SetPlaybackRate(float32 playback_rate);
/// Sets repeat mode to any of the supported repeat modes.
SetRepeatMode(RepeatMode repeat_mode);
/// Sets shuffle mode.
SetShuffleMode(bool shuffle_on);
/// Binds to the session's gain control for control and notifications.
request<> gain_control_request);
/// Binds to the session's volume control for control and notifications.
request<> volume_control_request);
table WatchOptions {
/// Watch only the active session. Watches all if not set.
1: bool only_active;
/// `SessionsWatcher` watches the collection of published sessions.
protocol SessionsWatcher {
/// Called by the registry service when a session is updated. On first connection,
/// this will be called as many times as needed to communicate the state of the
/// world.
/// `SessionsWatchers` must reply to acknlowledge receipt of the session info delta.
/// Delinquent watchers who do not reply will eventually be disconnected.
SessionUpdated(SessionId session_id, SessionInfoDelta session_info_delta) -> ();
/// Called by the registry service when a session is removed from the registered
/// collection.
/// `SessionsWatchers` must reply to acknlowledge receipt of the session removal.
/// Delinquent watchers who do not reply will eventually be disconnected.
SessionRemoved(SessionId session_id) -> ();
/// `Discovery` observes the collection of published media sessions
/// and connects clients to them.
protocol Discovery {
/// Connects a session watcher configured with the given options.
WatchOptions watch_options,
SessionsWatcher session_watcher);
/// Connects to a `SessionControl` for `session_id` if present. Drops the
/// given channel otherwise.
ConnectToSession(SessionId session_id,
request<SessionControl> session_control_request);