getYoutubeVideoURL.go

func getVideoURL(data url.Values) (string, error) {
  streamMap, ok := data["url_encoded_fmt_stream_map"]
	if !ok {
		err = errors.New(fmt.Sprint("no stream map found in the server's answer"))
		return err
	}

	// read each stream
	streamsList := strings.Split(streamMap[0], ",")

	// Get video title and author.
	title, author := getVideoTitleAuthor(answer)

	// Get video download link
	var streams []stream
	for streamPos, streamRaw := range streamsList {
		streamQry, err := url.ParseQuery(streamRaw)
		if err != nil {
			y.log(fmt.Sprintf("An error occured while decoding one of the video's stream's information: stream %d: %s\n", streamPos, err))
			continue
		}

		if _, ok := streamQry["quality"]; !ok {
			y.log(fmt.Sprintf("An empty video's stream's information: stream %d\n", streamPos))
			continue
		}

		streams = append(streams, stream{
			"quality": streamQry["quality"][0],
			"type":    streamQry["type"][0],
			"url":     streamQry["url"][0],

			"title":  title,
			"author": author,
		})
		y.log(fmt.Sprintf("Title: %s Author: %s Stream found: quality '%s', format '%s'", title, author, streamQry["quality"][0], streamQry["type"][0]))
    //2019/12/10 16:49:15 Title: dotGo 2015 - Rob Pike - Simplicity is Complicated Author: dotconferences Stream found: quality 'hd720', format 'video/mp4; codecs="avc1.64001F, mp4a.40.2"'
    //2019/12/10 16:49:15 Title: dotGo 2015 - Rob Pike - Simplicity is Complicated Author: dotconferences Stream found: quality 'medium', format 'video/webm; codecs="vp8.0, vorbis"'
    //2019/12/10 16:49:15 Title: dotGo 2015 - Rob Pike - Simplicity is Complicated Author: dotconferences Stream found: quality 'medium', format 'video/mp4; codecs="avc1.42001E, mp4a.40.2"'
	}
}