Initial work on downsampling

The http connection is being closed before sending all data. May have something to do with the Range header

api/get_cover_art.go

@@ -31,7 +31,7 @@ func (c *GetCoverArtController) Get() {
 
 	var img []byte
 
-	if mf.HasCoverArt {
+	if mf != nil && mf.HasCoverArt {
 		img, err = readFromTag(mf.Path)
 		beego.Debug("Serving cover art from", mf.Path)
 	} else {

api/stream.go

@@ -1,44 +1,93 @@
 package api
 
 import (
+	"github.com/astaxie/beego"
+	"github.com/deluan/gosonic/api/responses"
+	"github.com/deluan/gosonic/domain"
+	"github.com/deluan/gosonic/stream"
 	"github.com/deluan/gosonic/utils"
 	"github.com/karlkfi/inject"
-	"github.com/deluan/gosonic/domain"
-	"github.com/deluan/gosonic/api/responses"
-	"github.com/astaxie/beego"
 	"io"
-	"os"
+	"net/http"
+	"strconv"
 )
 
-
 type StreamController struct {
 	BaseAPIController
 	repo domain.MediaFileRepository
+	id   string
+	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)
-}
 
-// For realtime transcoding, see : http://stackoverflow.com/questions/19292113/not-buffered-http-responsewritter-in-golang
-func (c *StreamController) Get() {
-	id := c.GetParameter("id", "id parameter required")
+	c.id = c.GetParameter("id", "id parameter required")
 
-	mf, err := c.repo.Get(id)
+	mf, err := c.repo.Get(c.id)
 	if err != nil {
-		beego.Error("Error reading mediafile", id, "from the database", ":", err)
+		beego.Error("Error reading mediafile", c.id, "from the database", ":", err)
 		c.SendError(responses.ERROR_GENERIC, "Internal error")
 	}
-	beego.Debug("Streaming file", mf.Path)
 
-	f, err := os.Open(mf.Path)
-	if err != nil {
-		beego.Warn("Error opening file", mf.Path, "-", err)
-		c.SendError(responses.ERROR_DATA_NOT_FOUND, "cover art not available")
+	if mf == nil {
+		beego.Error("MediaFile", c.id, "not found!")
+		c.SendError(responses.ERROR_DATA_NOT_FOUND)
 	}
 
-	c.Ctx.Output.ContentType(mf.ContentType())
-	io.Copy(c.Ctx.ResponseWriter, f)
-
-	beego.Debug("Finished streaming of", mf.Path)
+	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("Bitrate", c.mf.BitRate, "MaxBitRate", maxBitRate)
+
+	if maxBitRate > 0 {
+		c.Ctx.Output.Header("Content-Length", strconv.Itoa(c.mf.Duration*maxBitRate*1000/8))
+	}
+	c.Ctx.Output.Header("Content-Type", "audio/mpeg")
+	c.Ctx.Output.Header("Expires", "0")
+	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))
+	if err != nil {
+		beego.Error("Error streaming file id", c.id, ":", err)
+	}
+
+	beego.Debug("Finished streaming of", c.mf.Path)
+}
+
+func (c *StreamController) Download() {
+	beego.Debug("Sending file", c.mf.Path)
+
+	stream.Stream(c.mf.Path, 0, 0, c.Ctx.ResponseWriter)
+
+	beego.Debug("Finished sending", c.mf.Path)
 }