Youtube integration

.drone.yml

@@ -9,4 +9,6 @@ steps:
       - go test -v
     environment:
       IMGUR_CLIENT_ID:
-        from_secret: imgur_client_id
+        from_secret: imgur_client_id
+      YOUTUBE_KEY:
+        from_secret: youtube_key

linkinfo.go

@@ -15,6 +15,7 @@ type LinkInfoApi struct {
 	Client *http.Client
 
 	Imgur        *ImgurInfoApi
+	Youtube      *YoutubeInfoApi
 	linkHandlers []*LinkHandler
 }
 
@@ -38,6 +39,8 @@ func New(opts ...Option) *LinkInfoApi {
 		switch opt.(type) {
 		case *ImgurOptions:
 			api.Imgur = &ImgurInfoApi{api, opt.(*ImgurOptions)}
+		case *YoutubeOptions:
+			api.Youtube = &YoutubeInfoApi{api, opt.(*YoutubeOptions)}
 		}
 	}
 
@@ -56,9 +59,11 @@ func (i *LinkInfoApi) registerDefaultHandlers() {
 		})
 	}
 
-	i.linkHandlers = []*LinkHandler{
-		{Hosts: youtubeHosts, Handler: i.YoutubeLinkHandler},
-		{Hosts: twitterHosts, Handler: i.TwitterLinkHandler},
+	if i.Youtube != nil {
+		i.linkHandlers = append(i.linkHandlers, &LinkHandler{
+			Hosts:   youtubeHosts,
+			Handler: i.Youtube.Handler,
+		})
 	}
 }
 

youtube.go

@@ -1,9 +1,147 @@
 package linkinfo
 
-var (
-	youtubeHosts = []string{"youtube.com", "youtu.be"}
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strings"
+	"time"
 )
 
-func (i *LinkInfoApi) YoutubeLinkHandler(link string) (*LinkInfo, error) {
-	return nil, nil
+const youtubeApiUrl = "https://www.googleapis.com/youtube/v3/videos"
+
+var (
+	youtubeHosts   = []string{"youtube.com", "youtu.be"}
+	durationRegexp = regexp.MustCompile("^00:")
+)
+
+type YoutubeOptions struct {
+	Option
+
+	Key string
+}
+
+type YoutubeInfoApi struct {
+	api  *LinkInfoApi
+	opts *YoutubeOptions
+}
+
+type youtubeResponse struct {
+	Error *youtubeError  `json:"error"`
+	Items []*youtubeItem `json:"items"`
+}
+
+type youtubeError struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+type youtubeItem struct {
+	Snippet        *youtubeSnippet        `json:"snippet"`
+	ContentDetails *youtubeContentDetails `json:"contentDetails"`
+}
+
+type youtubeSnippet struct {
+	Title       string `json:"title"`
+	Description string `json:"description"`
+}
+
+type youtubeContentDetails struct {
+	Duration string `json:"duration"`
+}
+
+func (i *YoutubeInfoApi) Handler(link string) (*LinkInfo, error) {
+	u, err := url.Parse(link)
+
+	if err != nil {
+		return nil, err
+	}
+
+	var id string
+
+	query := u.Query()
+
+	if query != nil && query.Get("v") != "" {
+		id = query.Get("v")
+	} else if u.Host == "youtu.be" {
+		id = u.Path[1:]
+	}
+
+	if id == "" {
+		return i.api.DefaultLinkHandler(link)
+	}
+
+	params := &url.Values{}
+
+	params.Set("id", id)
+	params.Set("part", "id, snippet, contentDetails")
+	params.Set("key", i.opts.Key)
+
+	req, err := http.NewRequest("GET", youtubeApiUrl+"?"+params.Encode(), nil)
+
+	if err != nil {
+		return nil, err
+	}
+
+	res, err := i.api.Client.Do(req)
+
+	if err != nil {
+		return nil, err
+	}
+
+	var response youtubeResponse
+
+	if err := json.NewDecoder(res.Body).Decode(&response); err != nil {
+		return nil, err
+	}
+
+	if response.Error != nil {
+		return nil, errors.New(response.Error.Message)
+	}
+
+	if len(response.Items) < 1 {
+		return nil, errors.New("video not found")
+	}
+
+	item := response.Items[0]
+
+	duration, err := time.ParseDuration(strings.ToLower(item.ContentDetails.Duration[2:]))
+
+	trimmedDuration := durationRegexp.ReplaceAllString(humanizeDuration(duration), "")
+
+	ret := &LinkInfo{
+		Title:       item.Snippet.Title + " [" + trimmedDuration + "]",
+		Description: item.Snippet.Description,
+		Duration:    item.ContentDetails.Duration,
+	}
+
+	return ret, nil
+}
+
+// https://gist.github.com/harshavardhana/327e0577c4fed9211f65#gistcomment-2366908
+func humanizeDuration(duration time.Duration) string {
+	hours := int64(duration.Hours())
+	minutes := int64(math.Mod(duration.Minutes(), 60))
+	seconds := int64(math.Mod(duration.Seconds(), 60))
+
+	chunks := []struct {
+		singularName string
+		amount       int64
+	}{
+		{"hour", hours},
+		{"minute", minutes},
+		{"second", seconds},
+	}
+
+	parts := make([]string, 0)
+
+	for _, chunk := range chunks {
+		parts = append(parts, fmt.Sprintf("%02d", chunk.amount))
+	}
+
+	return strings.Join(parts, ":")
 }

youtube_test.go

@@ -0,0 +1,22 @@
+package linkinfo
+
+import (
+	"os"
+	"testing"
+)
+
+func TestYoutubeInfoApi_Handler(t *testing.T) {
+	api := New(&YoutubeOptions{
+		Key: os.Getenv("YOUTUBE_KEY"),
+	})
+
+	info, err := api.Youtube.Handler("https://www.youtube.com/watch?v=1r4Md5WKaqs")
+
+	if err != nil {
+		t.Fatal("Error getting youtube info:", err)
+	}
+
+	if info.Title != "CHVRCHES - Graves [04:46]" {
+		t.Fatal("Unexpected title", info.Title)
+	}
+}