From 4f75e00f9df7a89c17ac52a1927deaf85ac23352 Mon Sep 17 00:00:00 2001
From: juancarmore <juancar_more2@hotmail.com>
Date: Mon, 23 Sep 2024 12:02:52 +0200
Subject: [PATCH] openvidu-recording-basic: Improve video seeking

---
 .../src/index.js                              | 27 ++++++++++++++++---
 .../src/s3.service.js                         | 21 +++++++--------
 2 files changed, 32 insertions(+), 16 deletions(-)

diff --git a/advanced-features/openvidu-recording-basic-node/src/index.js b/advanced-features/openvidu-recording-basic-node/src/index.js
index eba87f9e..bdb53a2a 100644
--- a/advanced-features/openvidu-recording-basic-node/src/index.js
+++ b/advanced-features/openvidu-recording-basic-node/src/index.js
@@ -14,6 +14,7 @@ const LIVEKIT_API_KEY = process.env.LIVEKIT_API_KEY || "devkey";
 const LIVEKIT_API_SECRET = process.env.LIVEKIT_API_SECRET || "secret";
 
 const RECORDINGS_PATH = process.env.RECORDINGS_PATH ?? "recordings/";
+const RECORDING_FILE_PORTION_SIZE = 5 * 1024 * 1024; // 5MB
 
 const app = express();
 
@@ -175,6 +176,7 @@ const getRecordingInfo = async (payloadKey) => {
 
 app.get("/recordings/:recordingName", async (req, res) => {
     const { recordingName } = req.params;
+    const { range } = req.headers;
     const key = RECORDINGS_PATH + recordingName;
     const exists = await s3Service.exists(key);
 
@@ -185,21 +187,38 @@ app.get("/recordings/:recordingName", async (req, res) => {
 
     try {
         // Get the recording file from S3
-        const { body, size } = await s3Service.getObject(key);
+        const { stream, size, start, end } = await getRecordingStream(recordingName, range);
 
-        // Set the response headers
+        // Set response headers
+        res.status(206);
+        res.setHeader("Cache-Control", "no-cache");
         res.setHeader("Content-Type", "video/mp4");
-        res.setHeader("Content-Length", size);
         res.setHeader("Accept-Ranges", "bytes");
+        res.setHeader("Content-Range", `bytes ${start}-${end}/${size}`);
+        res.setHeader("Content-Length", end - start + 1);
 
         // Pipe the recording file to the response
-        body.pipe(res).on("finish", () => res.end());
+        stream.pipe(res).on("finish", () => res.end());
     } catch (error) {
         console.error("Error getting recording.", error);
         res.status(500).json({ errorMessage: "Error getting recording" });
     }
 });
 
+const getRecordingStream = async (recordingName, range) => {
+    const key = RECORDINGS_PATH + recordingName;
+    const size = await s3Service.getObjectSize(key);
+
+    // Get the requested range
+    const parts = range?.replace(/bytes=/, "").split("-");
+    const start = range ? parseInt(parts[0], 10) : 0;
+    const endRange = parts[1] ? parseInt(parts[1], 10) : start + RECORDING_FILE_PORTION_SIZE;
+    const end = Math.min(endRange, size - 1);
+
+    const stream = await s3Service.getObject(key, { start, end });
+    return { stream, size, start, end };
+};
+
 app.delete("/recordings/:recordingName", async (req, res) => {
     const { recordingName } = req.params;
     const key = RECORDINGS_PATH + recordingName;
diff --git a/advanced-features/openvidu-recording-basic-node/src/s3.service.js b/advanced-features/openvidu-recording-basic-node/src/s3.service.js
index f8424552..cb224f54 100644
--- a/advanced-features/openvidu-recording-basic-node/src/s3.service.js
+++ b/advanced-features/openvidu-recording-basic-node/src/s3.service.js
@@ -54,22 +54,23 @@ export class S3Service {
     }
 
     async getObjectSize(key) {
-        const { ContentLength } = await this.headObject(key);
-        return ContentLength;
+        const { ContentLength: size } = await this.headObject(key);
+        return size;
     }
 
-    async getObject(key) {
+    async getObject(key, range) {
         const params = {
             Bucket: S3_BUCKET,
-            Key: key
+            Key: key,
+            Range: range ? `bytes=${range.start}-${range.end}` : undefined
         };
         const command = new GetObjectCommand(params);
-        const { Body: body, ContentLength: size } = await this.run(command);
-        return { body, size };
+        const { Body: body } = await this.run(command);
+        return body;
     }
 
     async getObjectAsJson(key) {
-        const { body } = await this.getObject(key);
+        const body = await this.getObject(key);
         const stringifiedData = await body.transformToString();
         return JSON.parse(stringifiedData);
     }
@@ -83,11 +84,7 @@ export class S3Service {
         const { Contents: objects } = await this.run(command);
 
         // Filter objects by regex and return the keys
-        return (
-            objects
-                ?.filter((object) => regex.test(object.Key))
-                .map((payload) => payload.Key) ?? []
-        );
+        return objects?.filter((object) => regex.test(object.Key)).map((payload) => payload.Key) ?? [];
     }
 
     async deleteObject(key) {