I *think* I got the downsampling working perfectly

api/stream.go

@@ -7,8 +7,6 @@ import (
 	"github.com/deluan/gosonic/stream"
 	"github.com/deluan/gosonic/utils"
 	"github.com/karlkfi/inject"
-	"io"
-	"net/http"
 	"strconv"
 )
 
@@ -19,19 +17,6 @@ type StreamController struct {
 	mf   *domain.MediaFile
 }
 
-type flushWriter struct {
-	f http.Flusher
-	w io.Writer
-}
-
-func (fw *flushWriter) Write(p []byte) (n int, err error) {
-	n, err = fw.w.Write(p)
-	if fw.f != nil {
-		fw.f.Flush()
-	}
-	return
-}
-
 func (c *StreamController) Prepare() {
 	inject.ExtractAssignable(utils.Graph, &c.repo)
 
@@ -51,21 +36,12 @@ func (c *StreamController) Prepare() {
 	c.mf = mf
 }
 
-func createFlusher(w http.ResponseWriter) io.Writer {
-	fw := flushWriter{w: w}
-	if f, ok := w.(http.Flusher); ok {
-		fw.f = f
-	}
-	return &fw
-}
-
-// TODO Investigate why it is not flushing before closing the connection
 func (c *StreamController) Stream() {
 	var maxBitRate int
 	c.Ctx.Input.Bind(&maxBitRate, "maxBitRate")
 	maxBitRate = utils.MinInt(c.mf.BitRate, maxBitRate)
 
-	beego.Debug("Streaming file", maxBitRate, ":", c.mf.Path)
+	beego.Debug("Streaming file", ":", c.mf.Path)
 	beego.Debug("Bitrate", c.mf.BitRate, "MaxBitRate", maxBitRate)
 
 	if maxBitRate > 0 {
@@ -76,7 +52,7 @@ func (c *StreamController) Stream() {
 	c.Ctx.Output.Header("Cache-Control", "must-revalidate")
 	c.Ctx.Output.Header("Pragma", "public")
 
-	err := stream.Stream(c.mf.Path, c.mf.BitRate, maxBitRate, createFlusher(c.Ctx.ResponseWriter))
+	err := stream.Stream(c.mf.Path, c.mf.BitRate, maxBitRate, c.Ctx.ResponseWriter)
 	if err != nil {
 		beego.Error("Error streaming file id", c.id, ":", err)
 	}

stream/downsampling.go

@@ -12,14 +12,19 @@ import (
 func Stream(path string, bitRate int, maxBitRate int, w io.Writer) error {
 	if maxBitRate > 0 && bitRate > maxBitRate {
 		cmdLine, args := createDownsamplingCommand(path, maxBitRate)
-		cmd := exec.Command(cmdLine, args...)
-		beego.Debug("Executing cmd:", cmdLine, args)
 
-		cmd.Stdout = w
+		beego.Debug("Executing cmd:", cmdLine, args)
+		cmd := exec.Command(cmdLine, args...)
 		cmd.Stderr = os.Stderr
-		err := cmd.Run()
+		stdout, err := cmd.StdoutPipe()
 		if err != nil {
 			beego.Error("Error executing", cmdLine, ":", err)
+			return err
+		}
+		if err = cmd.Start(); err != nil {
+			beego.Error("Error executing", cmdLine, ":", err)
+		} else {
+			_, err = io.Copy(w, stdout)
 		}
 		return err
 	} else {