// main starts a sift server and listens for updates, printing any to console.
func repeatUpdatesToConsole(server *sift.Server) {
myToken := server.Login()
updateChan := server.Listen(myToken) // without specifying filters, this will listen to everything
fmt.Println("listening to SIFT server and printing updates to console...")
for {
update := <-updateChan //TODO: uncaught panic if updateChan is closed
switch typed := update.(type) {
case notif.ComponentNotification:
color.Blue("component %+v %v: %+v\n", typed.ID, typed.Action, typed.Component)
//case notif.DriverNotification:
// fmt.Printf("driver %v: %v", typed.NotificationType, typed.Component)
default:
color.Red("unhandled update type from updateChan: %T (%v)\n", update, update)
}
}
}
// This SIFT app will turn the lights down in any room with a running media
// player. If there are no running media players, the lights will be set to
// high.
func moviesAndChill(server *sift.Server) {
if server == nil { // sanity check
return
}
token := server.Login() // authenticate with SIFT
// SIFT apps can request notifications from SIFT to determine when they
// should do something. For this app, we'll want to know when media players
// change (e.g. if they are added or their states change), and when lights
// change (e.g. if they are added, moved, or removed)
mediaFilter := notif.ComponentFilter{Type: types.ComponentTypeMediaPlayer}
lightsFilter := notif.ComponentFilter{Type: types.ComponentTypeLightEmitter}
listener := server.Listen(token, lightsFilter, mediaFilter) // this starts listening
for range listener {
// Each time the listener receives a notification, this example will
// recalculate the lighting values for each light.
// (A better implementation might look at the updates and only
// recalculate those that need to be recalculated)
// Run a query against the SIFT sqlite database to find each available
// light and the number of PLAYING media players in the same room.
lightsQuery := `
SELECT c1.device_id, c1.name, num_playing_mpls_in_room
FROM light_emitter_state l1
JOIN component c1 ON l1.id=c1.id
JOIN device d1 ON c1.device_id=d1.id
JOIN (SELECT d.location_id loc,
SUM (CASE WHEN m.play_state="PLAYING" THEN 1 ELSE 0 END) as num_playing_mpls_in_room
FROM media_player_state m
JOIN component c ON m.id=c.id
JOIN device d ON c.device_id=d.id
GROUP BY d.location_id)
ON d1.location_id=loc;`
type result struct {
DeviceID int64 `db:"device_id"`
Name string
NumPlayingMediaPlayersInRoom int `db:"num_playing_mpls_in_room"`
}
results := []result{}
db, _ := server.DB()
// run the query
if err := db.Select(&results, lightsQuery); err != nil {
panic(fmt.Sprintf("could not run query to get active media players: %v", err))
}
// Check out the results and determine how each light should be set. In
// SIFT, this is done using Intents.
for _, result := range results {
var intent types.SetLightEmitterIntent
if result.NumPlayingMediaPlayersInRoom > 0 { // a movie is playing in the room ...
intent.BrightnessInPercent = lightsLow // ...bring the lights down low
} else { // no movies in this room...
intent.BrightnessInPercent = lightsHigh // ...bring the lights up
}
target := types.ComponentID{
DeviceID: types.DeviceID(result.DeviceID),
Name: result.Name,
}
// Send the intent to the SIFT server, which will make it real
if err := server.EnactIntent(target, intent); err != nil {
fmt.Printf("warning: could not enact intent: %v\n", err)
}
}
}
}