RTSP Stream Relay with Dockerized Node.js Application

This project is a Node.js application designed to relay RTSP streams over WebSocket using rtsp-relay and FFmpeg. It runs inside a Docker container, providing a convenient and isolated environment for streaming RTSP feeds.

Example Usage

const createRTSPStreamServer = require('rtsp-stream-relay');

// Create the server on port 3000
const app = createRTSPStreamServer(3000);

Features

• Relays RTSP streams over WebSocket.
• Configured to work with FFmpeg for handling multimedia streams.
• Containerized using Docker for easy deployment.
• Exposes two ports for HTTP and WebSocket traffic.

Prerequisites

• Docker installed on your machine.
• Node.js version 18.x and Yarn package manager (installed inside the container).

Installation

Clone the Repository

git clone https://github.com/your-repository/rtsp-relay-app.git
cd rtsp-relay-app

Build the Docker Image

1. Build the Docker image using the provided Dockerfile:

docker build -t rtsp-relay-app .

2. Once the image is built, you can start the container:

docker run -p 3000:3000 -p 8000:8000 rtsp-relay-app

This will expose ports 3000 and 8000 to your local machine, which can be used for the application's HTTP and WebSocket traffic.

Application Usage

1. After starting the Docker container, the application will be accessible at http://localhost:3000 or via WebSocket at ws://localhost:8000.

2. To start streaming an RTSP feed, connect to the WebSocket endpoint /api/stream with a query parameter specifying the RTSP stream URL.

Example:

ws://localhost:8000/api/stream?url=rtsp://your-rtsp-url

The server will relay the RTSP feed over WebSocket.

Dockerfile Overview

The application is containerized using the following Dockerfile:

FROM ubuntu:22.04

RUN apt-get update && apt-get install -y ffmpeg

RUN apt-get install -y curl
RUN curl -fsSL https://deb.nodesource.com/setup_18.x | bash -
RUN apt-get install -y nodejs

RUN npm install -g yarn

EXPOSE 3000
EXPOSE 8000

WORKDIR /app

COPY package.json yarn.lock ./

RUN yarn

COPY . .

CMD ["node", "index.js"]

Explanation:

1. Base Image: Uses Ubuntu 22.04 as the base image.
2. FFmpeg Installation: Installs FFmpeg for multimedia processing.
3. Node.js Installation: Installs Node.js 18.x via the NodeSource repository.
4. Yarn Installation: Installs Yarn as the package manager.
5. Expose Ports: Exposes ports 3000 (for HTTP) and 8000 (for WebSocket).
6. Application Setup: Copies the application code and installs dependencies using Yarn.
7. Startup Command: Runs the Node.js application with index.js.

Development

To make changes and run the application without Docker, follow these steps:

1. Install the required dependencies:

yarn install

2. Start the Node.js application locally:

node index.js

By default, the application will listen on port 3000 for HTTP requests and 8000 for WebSocket connections.

Configuration

You can modify the following parameters:

• Ports: You can change the exposed ports by modifying the EXPOSE instructions in the Dockerfile or updating the docker run command with different port mappings.
• Transport Protocol: By default, the transport protocol for the RTSP stream is tcp. You can change it in the handler function inside index.js.
• Additional FFmpeg Flags: Adjust or add FFmpeg flags to control stream quality or other aspects by modifying the additionalFlags array.

Example Usage with React

To use the RTSP stream relay in a React application, you can create a WebSocket connection and display the stream in a video element using the MediaSource API.

Step-by-Step:

1. Install the required dependencies in your React app if needed:

   npm install react react-dom

2. Create a React component that establishes the WebSocket connection and displays the RTSP stream:

import React, { useEffect, useRef } from "react";

const RTSPStream = ({ streamUrl }) => {
  const videoRef = useRef(null);

  useEffect(() => {
    const ws = new WebSocket(`ws://localhost:8000/api/stream?url=${streamUrl}`);

    ws.onopen = () => {
      console.log("WebSocket connection established");
    };

    ws.onmessage = (event) => {
      const video = videoRef.current;
      const mediaSource = new MediaSource();
      video.src = URL.createObjectURL(mediaSource);

      mediaSource.addEventListener("sourceopen", () => {
        const sourceBuffer = mediaSource.addSourceBuffer('video/mp4; codecs="avc1.42E01E"');
        sourceBuffer.appendBuffer(event.data);
      });
    };

    ws.onerror = (error) => {
      console.error("WebSocket error:", error);
    };

    ws.onclose = () => {
      console.log("WebSocket connection closed");
    };

    return () => ws.close();
  }, [streamUrl]);

  return (
    <div>
      <video ref={videoRef} controls autoPlay style={{ width: "100%" }} />
    </div>
  );
};

export default RTSPStream;

Usage in a React App:

import React from "react";
import ReactDOM from "react-dom";
import RTSPStream from "./RTSPStream";

const App = () => {
  return (
    <div>
      <h1>RTSP Stream Example</h1>
      <RTSPStream streamUrl="rtsp://your-rtsp-url" />
    </div>
  );
};

ReactDOM.render(<App />, document.getElementById("root"));

This will establish a WebSocket connection to your RTSP stream, and the video will be rendered in the video element.

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Example Usage with Plain HTML and JavaScript

For an HTML-based solution, you can similarly use the MediaSource API and WebSocket connection to handle the RTSP stream relay.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>RTSP Stream Example</title>
</head>
<body>
  <h1>RTSP Stream Example</h1>
  <video id="video" controls autoplay style="width: 100%;"></video>

  <script>
    const video = document.getElementById('video');
    const streamUrl = 'rtsp://your-rtsp-url';
    const ws = new WebSocket(`ws://localhost:8000/api/stream?url=${streamUrl}`);

    ws.onopen = function() {
      console.log('WebSocket connection established');
    };

    ws.onmessage = function(event) {
      const mediaSource = new MediaSource();
      video.src = URL.createObjectURL(mediaSource);

      mediaSource.addEventListener('sourceopen', function() {
        const sourceBuffer = mediaSource.addSourceBuffer('video/mp4; codecs="avc1.42E01E"');
        sourceBuffer.appendBuffer(event.data);
      });
    };

    ws.onerror = function(error) {
      console.error('WebSocket error:', error);
    };

    ws.onclose = function() {
      console.log('WebSocket connection closed');
    };
  </script>
</body>
</html>

Explanation:

• This HTML file creates a WebSocket connection to the RTSP relay server.
• The MediaSource API is used to stream the video data received from the WebSocket to the video element.
• The WebSocket URL includes a query parameter for the RTSP stream URL (rtsp://your-rtsp-url), which must be replaced with your actual RTSP feed.

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