feat/add-thumbnail-caching (#3)

Co-authored-by: Priyanshubhartistm <bhartipriyanshustm@gmail.com>
Co-committed-by: Priyanshubhartistm <bhartipriyanshustm@gmail.com>

index.js

@@ -1,44 +1,78 @@
-import express from "express"
-import ffmpeg from "fluent-ffmpeg"
-import {PassThrough} from "stream"
+import express from "express";
+import ffmpeg from "fluent-ffmpeg";
+import { PassThrough } from "stream";
+import NodeCache from "node-cache";
+import ffmpegInstaller from "@ffmpeg-installer/ffmpeg";
 
-const app = express()
-const PORT = process.env.PORT || 3100
+ffmpeg.setFfmpegPath(ffmpegInstaller.path);
 
-app.get("/thumbnail", async (req, res) => {
-  const videoUrl = req.query.url
+const app = express();
+const PORT = process.env.PORT || 3100;
+
+const thumbnailCache = new NodeCache({
+  stdTTL: 3600,
+  checkperiod: 600,
+  useClones: false
+});
+
+app.get("/thumbnail", (req, res) => {
+  const videoUrl = req.query.url?.trim();
 
   if (!videoUrl) {
-    return res.status(400).json({error: "Missing 'url' query parameter"})
+    return res.status(400).json({ error: "Missing 'url' query parameter" });
+  }
+
+  const cachedImage = thumbnailCache.get(videoUrl);
+  if (cachedImage) {
+    res.setHeader("Content-Type", "image/jpeg");
+    res.setHeader("Cache-Control", "public, max-age=86400");
+    return res.send(cachedImage);
   }
 
   try {
-    const passthrough = new PassThrough()
+    const passthrough = new PassThrough();
+    let imageBuffer = Buffer.alloc(0);
+
+    passthrough.on("data", (chunk) => {
+      imageBuffer = Buffer.concat([imageBuffer, chunk]);
+    });
+
+    passthrough.on("end", () => {
+      if (imageBuffer.length > 0) {
+        thumbnailCache.set(videoUrl, imageBuffer);
+      }
+    });
 
     ffmpeg(videoUrl)
       .seekInput(1)
       .frames(1)
       .format("image2")
       .outputOptions("-vcodec", "mjpeg")
-      .on("error", err => {
+      .on("error", (err) => {
+        console.error("ffmpeg error:", err.message);
         if (!res.headersSent) {
-          res.status(500).json({error: "Failed to generate thumbnail"})
+          res.status(500).json({ error: "Failed to generate thumbnail" });
         }
       })
-      .pipe(passthrough, {end: true})
+      .pipe(passthrough, { end: true });
 
-    res.setHeader("Content-Type", "image/jpeg")
-    res.setHeader("Cache-Control", "public, max-age=86400")
-    passthrough.pipe(res)
-  } catch {
-    res.status(500).json({error: "Failed to process video"})
+    res.setHeader("Content-Type", "image/jpeg");
+    res.setHeader("Cache-Control", "public, max-age=86400");
+
+    passthrough.pipe(res);
+
+  } catch (err) {
+    console.error("Error:", err);
+    if (!res.headersSent) {
+      res.status(500).json({ error: "Failed to process video" });
+    }
   }
-})
+});
 
 app.get("/health", (_req, res) => {
-  res.json({status: "ok"})
-})
+  res.json({ status: "ok" });
+});
 
 app.listen(PORT, () => {
-  console.log(`Video thumbnail service running on port ${PORT}`)
-})
+  console.log(`Video thumbnail service running on port ${PORT}`);
+});