Merge pull request #178 from wader/download-error

Handle errors at download better

cmd/goutubedl/main.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"log"
 	"os"
+	"os/exec"
 
 	"github.com/wader/goutubedl"
 )
@@ -24,7 +25,11 @@ func main() {
 	result, err := goutubedl.New(
 		context.Background(),
 		flag.Arg(0),
-		goutubedl.Options{Type: optType, DebugLog: log.Default()},
+		goutubedl.Options{
+			Type:     optType,
+			DebugLog: log.Default(),
+			StderrFn: func(cmd *exec.Cmd) io.Writer { return os.Stderr },
+		},
 	)
 	if err != nil {
 		log.Fatal(err)

goutubedl.go

@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"net/http"
 	"os"
 	"os/exec"
@@ -129,7 +128,7 @@ type Info struct {
 	WebpageURL  string `json:"webpage_url"`
 	Description string `json:"description"`
 	Thumbnail   string `json:"thumbnail"`
-	// not unmarshalled, populated from image thumbnail file
+	// don't unmarshal, populated from image thumbnail file
 	ThumbnailBytes []byte      `json:"-"`
 	Thumbnails     []Thumbnail `json:"thumbnails"`
 
@@ -180,7 +179,7 @@ type Subtitle struct {
 	URL      string `json:"url"`
 	Ext      string `json:"ext"`
 	Language string `json:"-"`
-	// not unmarshalled, populated from subtitle file
+	// don't unmarshal, populated from subtitle file
 	Bytes []byte `json:"-"`
 }
 
@@ -346,15 +345,15 @@ func infoFromURL(
 	case TypeAny:
 		break
 	default:
-		return Info{}, nil, fmt.Errorf("Unhandle options type value: %d", options.Type)
+		return Info{}, nil, fmt.Errorf("unhandled options type value: %d", options.Type)
 	}
 
-	tempPath, _ := ioutil.TempDir("", "ydls")
+	tempPath, _ := os.MkdirTemp("", "ydls")
 	defer os.RemoveAll(tempPath)
 
 	stdoutBuf := &bytes.Buffer{}
 	stderrBuf := &bytes.Buffer{}
-	stderrWriter := ioutil.Discard
+	stderrWriter := io.Discard
 	if options.StderrFn != nil {
 		stderrWriter = options.StderrFn(cmd)
 	}
@@ -428,7 +427,7 @@ func infoFromURL(
 	if options.DownloadThumbnail && info.Thumbnail != "" {
 		resp, respErr := get(info.Thumbnail)
 		if respErr == nil {
-			buf, _ := ioutil.ReadAll(resp.Body)
+			buf, _ := io.ReadAll(resp.Body)
 			resp.Body.Close()
 			info.ThumbnailBytes = buf
 		}
@@ -445,7 +444,7 @@ func infoFromURL(
 			for i, subtitle := range subtitles {
 				resp, respErr := get(subtitle.URL)
 				if respErr == nil {
-					buf, _ := ioutil.ReadAll(resp.Body)
+					buf, _ := io.ReadAll(resp.Body)
 					resp.Body.Close()
 					subtitles[i].Bytes = buf
 				}
@@ -464,21 +463,21 @@ func infoFromURL(
 	// - entries that are more than 2 levels deep (will be missed)
 	// - the ability to restrict entries to a single level (we include both levels)
 	if options.Type == TypePlaylist || options.Type == TypeChannel {
-		var filteredEntrise []Info
+		var filteredEntries []Info
 		for _, e := range info.Entries {
 			if e.Type == "playlist" {
 				for _, ee := range e.Entries {
 					if ee.ID == "" {
 						continue
 					}
-					filteredEntrise = append(filteredEntrise, ee)
+					filteredEntries = append(filteredEntries, ee)
 				}
 				continue
 			} else if e.ID != "" {
-				filteredEntrise = append(filteredEntrise, e)
+				filteredEntries = append(filteredEntries, e)
 			}
 		}
-		info.Entries = filteredEntrise
+		info.Entries = filteredEntries
 	}
 
 	return info, stdoutBuf.Bytes(), nil
@@ -533,7 +532,7 @@ func (result Result) DownloadWithOptions(
 		}
 	}
 
-	tempPath, tempErr := ioutil.TempDir("", "ydls")
+	tempPath, tempErr := os.MkdirTemp("", "ydls")
 	if tempErr != nil {
 		return nil, tempErr
 	}
@@ -541,7 +540,7 @@ func (result Result) DownloadWithOptions(
 	var jsonTempPath string
 	if !result.Options.noInfoDownload {
 		jsonTempPath = path.Join(tempPath, "info.json")
-		if err := ioutil.WriteFile(jsonTempPath, result.RawJSON, 0600); err != nil {
+		if err := os.WriteFile(jsonTempPath, result.RawJSON, 0600); err != nil {
 			os.RemoveAll(tempPath)
 			return nil, err
 		}
@@ -624,15 +623,17 @@ func (result Result) DownloadWithOptions(
 	}
 
 	cmd.Dir = tempPath
-	var w io.WriteCloser
+	var stdoutW io.WriteCloser
-	dr.reader, w = io.Pipe()
+	var stderrW io.WriteCloser
-
+	var stderrR io.Reader
-	stderrWriter := ioutil.Discard
+	dr.reader, stdoutW = io.Pipe()
+	stderrR, stderrW = io.Pipe()
+	optStderrWriter := io.Discard
 	if result.Options.StderrFn != nil {
-		stderrWriter = result.Options.StderrFn(cmd)
+		optStderrWriter = result.Options.StderrFn(cmd)
 	}
-	cmd.Stdout = w
+	cmd.Stdout = stdoutW
-	cmd.Stderr = stderrWriter
+	cmd.Stderr = io.MultiWriter(optStderrWriter, stderrW)
 
 	debugLog.Print("cmd", " ", cmd.Args)
 	if err := cmd.Start(); err != nil {
@@ -642,12 +643,32 @@ func (result Result) DownloadWithOptions(
 
 	go func() {
 		_ = cmd.Wait()
-		w.Close()
+		stdoutW.Close()
+		stderrW.Close()
 		os.RemoveAll(tempPath)
 		close(dr.waitCh)
 	}()
 
-	return dr, nil
+	// blocks return until yt-dlp is downloading or has errored
+	ytErrCh := make(chan error)
+	go func() {
+		stderrLineScanner := bufio.NewScanner(stderrR)
+		for stderrLineScanner.Scan() {
+			const downloadPrefix = "[download]"
+			const errorPrefix = "ERROR: "
+			line := stderrLineScanner.Text()
+			if strings.HasPrefix(line, downloadPrefix) {
+				break
+			} else if strings.HasPrefix(line, errorPrefix) {
+				ytErrCh <- errors.New(line[len(errorPrefix):])
+				return
+			}
+		}
+		ytErrCh <- nil
+		_, _ = io.Copy(io.Discard, stderrR)
+	}()
+
+	return dr, <-ytErrCh
 }
 
 func (dr *DownloadResult) Read(p []byte) (n int, err error) {

goutubedl_test.go

@@ -552,3 +552,29 @@ func TestDownloadPlaylistEntry(t *testing.T) {
 		t.Error("not the same content between the playlist index entry and the direct link entry")
 	}
 }
+
+func TestFormatDownloadError(t *testing.T) {
+	defer leaktest.Check(t)()
+
+	ydl, ydlErr := goutubedl.New(
+		context.Background(),
+		"https://www.reddit.com/r/newsbabes/s/92rflI0EB0",
+		goutubedl.Options{},
+	)
+
+	if ydlErr != nil {
+		// reddit seems to not like github action hosts
+		if strings.Contains(ydlErr.Error(), "HTTPError 403: Blocked") {
+			t.Skip()
+		}
+		t.Error(ydlErr)
+	}
+
+	// no pre-muxed audio/video format available
+	_, ytDlErr := ydl.Download(context.Background(), "best")
+	expectedErr := "Requested format is not available"
+	if ydlErr != nil && !strings.Contains(ytDlErr.Error(), expectedErr) {
+		t.Errorf("expected error prefix %q got %q", expectedErr, ytDlErr.Error())
+
+	}
+}