Use memmap to cache json replies from ytdl

ytdl/ytdl.go

@@ -3,13 +3,24 @@ package ytdl
 import (
 	"errors"
 	"fmt"
+	"log"
 	"os/exec"
 	"path/filepath"
 	"time"
 
+	"github.com/gohugoio/hugo/cache/filecache"
+	"github.com/spf13/afero"
 	"github.com/tidwall/gjson"
 )
 
+var cache *filecache.Cache
+var yturl = "https://youtu.be/%s"
+
+func init() {
+	fs := afero.NewMemMapFs()
+	cache = filecache.NewCache(fs, 6*time.Hour, "")
+}
+
 type YTdl struct {
 	Title   string
 	Url     string
@@ -17,19 +28,30 @@ type YTdl struct {
 	Len     time.Duration
 }
 
-func NewYTdl(uri string) (*YTdl, error) {
-	ytdl_js, err := exec.Command(
-		"./bin/yt-dlp_linux",
-		uri,
-		"--cookies", "./cookies.txt",
-		"--no-call-home",
-		"--no-cache-dir",
-		"--ignore-errors",
-		"--newline",
-		"--restrict-filenames",
-		"-f", "140",
-		"-j",
-	).Output()
+func NewYTdl(vid string) (*YTdl, error) {
+	log.Printf("Loading %s from youtube\n", vid)
+	_, ytdl_js, err := cache.GetOrCreateBytes(vid+".json", func() ([]byte, error) {
+		log.Printf("%s not found in cache, downloading info.\n", vid)
+		js, err := exec.Command(
+			"./bin/yt-dlp_linux",
+			fmt.Sprintf(yturl, vid),
+			"--cookies", "./cookies.txt",
+			"--no-call-home",
+			"--no-cache-dir",
+			"--ignore-errors",
+			"--newline",
+			"--restrict-filenames",
+			"-f", "140",
+			"-j",
+		).Output()
+		if err != nil {
+			return nil, err
+		}
+
+		log.Printf("%s is now cached.\n", vid)
+
+		return js, nil
+	})
 
 	if err != nil {
 		return nil, err