uplink/plugins/test/sine/instance.go

package sine

import (
	"io"
	"log"
	"time"

	"git.icedream.tech/icedream/uplink/app/channels"
	humanize "github.com/dustin/go-humanize"
	"github.com/viert/lame"
)

type pluginInstance struct {
	channelManager *channels.ChannelManager
}

func (instance *pluginInstance) SetChannelManager(channelManager *channels.ChannelManager) {
	instance.channelManager = channelManager
}

func (instance *pluginInstance) Init() {
	channelManager := instance.channelManager

	go func() {
		time.Sleep(2 * time.Second) // give burst cache a chance to realize

		c, err := channelManager.Open("sine")
		if err != nil {
			log.Println("ERROR: sine channel could not be opened:", err)
			log.Println("Skipping sine channel creation")
			return
		}

		go func() {
			lastTime := time.Now()
			for {
				lastTime = lastTime.Add(time.Second)
				time.Sleep(time.Until(lastTime))

				c.SetMetadata(map[string]string{
					"StreamTitle": "beep - time: " + time.Now().String(),
				})
			}
		}()

		outputStream := c.AddOutputStream("mp3")
		defer outputStream.Close()

		outputContainer := c.AddOutputContainer("mp3")
		defer outputContainer.Close()

		w := io.MultiWriter(
			outputContainer,
			outputStream,
		)

		wr := lame.NewWriter(w)
		wr.Encoder.SetBitrate(192)
		wr.Encoder.SetQuality(1)
		wr.Encoder.SetInSamplerate(44100)
		wr.Encoder.SetNumChannels(2)
		wr.Encoder.InitParams()

		log.Println("Sine stream goroutine started")

		sine := new(SineStream)
		sine.Samplerate = 44100
		sine.Frequency = 990
		sine.Beep = true
		sine.Timestamp = time.Now()

		log.Println("Will now broadcast sine stream")
		n, err := io.Copy(wr, sine)
		if err != nil {
			log.Fatal("Sine stream copy failed:", err)
		}
		log.Println("Sine stream finished, written", humanize.Bytes(uint64(n)), "bytes")
	}()
}