Change module name and restructure contentv0.1.2

The repository names for soundbox are named as below:

- app: soundbox-app
- Go library module: soundbox-go
- Device: soundbox

The Go module names were:

- app: xengineering.eu/soundbox/app
- Go library module: xengineering.eu/soundbox

This does not make clear which module is related to which repository
since the names are different. Thus it should be changed to:

- app: xengineering.eu/soundbox-app
- Go library module: xengineering.eu/soundbox-go

The import statement for the library is then:

    import "xengineering.eu/soundbox-go/soundbox"

This is a bit longer but it keeps the property that the library is
referenced inside the code by the simple name `soundbox`.

1 files changed, 48 insertions, 0 deletions

diff --git a/soundbox/stream.go b/soundbox/stream.go
new file mode 100644
index 0000000..cc8fcea
--- /dev/null
+++ b/soundbox/stream.go
@@ -0,0 +1,48 @@
+package soundbox
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"net"
+)
+
+// streamingPort is the default network port a soundbox is listening to for
+// incoming audio stream data.
+const streamingPort = 5316
+
+// StreamURLContext streams audio from a given URL to one or multiple soundbox
+// devices. The devices are referenced via their MAC addresses given by the
+// targets argument. The ctx argument is passed to cancel the streaming.
+func StreamURLContext(ctx context.Context, url string, targets []net.HardwareAddr) error {
+	iface, err := getInterface()
+	if err != nil {
+		return err
+	}
+
+	cmd := []string{
+		"-re",
+		"-i",
+		url,
+	}
+
+	for _, target := range targets {
+		ip, err := toLinkLocal(target)
+		if err != nil {
+			return err
+		}
+
+		cmd = append(cmd, "-acodec")
+		cmd = append(cmd, "flac")
+		cmd = append(cmd, "-f")
+		cmd = append(cmd, "ogg")
+		cmd = append(cmd, fmt.Sprintf(
+			"tcp://[%s%%%s]:%d",
+			ip,
+			iface.Name,
+			streamingPort,
+		))
+	}
+
+	return exec.CommandContext(ctx, "ffmpeg", cmd...).Run()
+}