owncast/test/load/chatLoadTest.js

const WebSocket = require('ws');
const fetch = require('node-fetch');

var connectionCount = 0;
const targetConnectionCount = 5000;

const messages = [
  'I am a test message',
  'this is fake',
  'i write emoji 😀',
  'Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.',
  'Sed pulvinar proin gravida hendrerit. Mauris in aliquam sem fringilla ut morbi tincidunt augue. In cursus turpis massa tincidunt dui.',
  'Feugiat in ante metus dictum at tempor commodo ullamcorper. Nunc aliquet bibendum enim facilisis gravida neque convallis a. Vitae tortor condimentum lacinia quis vel eros donec ac odio.',
  'Here is _some_ **markdown**!',
];

var availableMessages = messages.slice();


async function registerChat() {
  const options = {
      method: 'POST',
      headers: {
          'Content-Type': 'application/json'
      }
  }

  try {
      const response = await fetch('http://localhost:8080/api/chat/register', options);
      const result = await response.json();
      return result;
  } catch(e) {
      console.error(e);
  }
}

async function runSingleUserIteration() {
  const registration = await registerChat();
  const accessToken = registration.accessToken;

  function sendTestMessage() {
    if (availableMessages.length == 0) {
      availableMessages = messages.slice();
    }
  
    const messageIndex = Math.floor(Math.random() * availableMessages.length);
    const message = availableMessages[messageIndex];
    availableMessages.splice(messageIndex, 1);
  
    const testMessage = {
      body: message,
      type: 'CHAT',
    };
  
    ws.send(JSON.stringify(testMessage));
  
    // After this message is sent then run it again.
    setTimeout(runSingleUserIteration, 20);
  }
  
  const ws = new WebSocket(`ws://localhost:8080/ws?accessToken=${accessToken}`, {
    origin: 'http://localhost:8080',
  });

  // When the websocket connects then send a chat message.
  ws.on('open', function open() {
    connectionCount++;
    console.log(connectionCount + '/' + targetConnectionCount, " chat clients.")
    if (connectionCount === targetConnectionCount) {
        process.exit();
    }
    setTimeout(sendTestMessage, 5);
  });

  ws.on('error', function incoming(data) {
    console.error(data);
  });
}

runSingleUserIteration();