Introduce io.Reader-based streamContext()

This prepares the switch to adding more sources than web URLs.
Everything providing an io.Reader can then simply use this internal
function in the background to avoid code duplication.

1 files changed, 50 insertions, 0 deletions

diff --git a/soundbox/streaming.go b/soundbox/streaming.go
new file mode 100644
index 0000000..5852dcf
--- /dev/null
+++ b/soundbox/streaming.go
@@ -0,0 +1,50 @@
+package soundbox
+
+import (
+	"context"
+	"errors"
+	"io"
+	"net"
+	"time"
+)
+
+const bufferSize = 20
+
+const writeTimeout = 1 * time.Second
+
+func streamContext(ctx context.Context, r io.Reader, targets []net.HardwareAddr) error {
+	conns := make([]net.Conn, 0)
+	for _, target := range targets {
+		conn, err := dialContext(ctx, target)
+		if err != nil {
+			return err
+		}
+		conns = append(conns, conn)
+	}
+	defer func() {
+		for _, conn := range conns {
+			conn.Close()
+		}
+	}()
+
+	for {
+		buffer := make([]byte, bufferSize)
+		i, err := r.Read(buffer)
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			} else {
+				return err
+			}
+		}
+		for _, conn := range conns {
+			conn.SetDeadline(time.Now().Add(writeTimeout))
+			_, err = conn.Write(buffer[:i])
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}