Chrome Extension to Local Agent Communication

chrome_ext_local_agent.js

// manifest.json
{
  "name": "Local Agent Connector",
  "version": "1.0",
  "manifest_version": 3,
  "permissions": [
    "nativeMessaging",
    "tabs"
  ],
  "background": {
    "service_worker": "background.js"
  },
  "host_permissions": ["http://127.0.0.1:*/*"]
}

// background.js
let port = null;
let wsConnection = null;

// Method 1: Native Messaging
chrome.runtime.onStartup.addListener(() => {
  // Connect to native host application
  port = chrome.runtime.connectNative('com.example.local_agent');
  
  port.onMessage.addListener((message) => {
    console.log('Received from native app:', message);
  });
  
  port.onDisconnect.addListener(() => {
    console.log('Disconnected from native app');
    port = null;
  });
});

// Method 2: WebSocket Connection
function connectWebSocket() {
  wsConnection = new WebSocket('ws://127.0.0.1:8080');
  
  wsConnection.onopen = () => {
    console.log('WebSocket Connected');
  };
  
  wsConnection.onmessage = (event) => {
    console.log('Received from WebSocket:', event.data);
  };
  
  wsConnection.onclose = () => {
    console.log('WebSocket closed, attempting reconnect...');
    setTimeout(connectWebSocket, 5000);
  };
}

// Method 3: HTTP Communication
async function sendToLocalAgent(data) {
  try {
    const response = await fetch('http://127.0.0.1:8080/api/data', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify(data)
    });
    return await response.json();
  } catch (error) {
    console.error('Error communicating with local agent:', error);
  }
}

// Example local agent (Node.js)
const WebSocket = require('ws');
const express = require('express');
const cors = require('cors');
const app = express();

// HTTP Server Setup
app.use(cors());
app.use(express.json());

app.post('/api/data', (req, res) => {
  console.log('Received data:', req.body);
  res.json({ status: 'success' });
});

const httpServer = app.listen(8080);

// WebSocket Server Setup
const wss = new WebSocket.Server({ server: httpServer });

wss.on('connection', (ws) => {
  console.log('Client connected');
  
  ws.on('message', (message) => {
    console.log('Received:', message);
    // Process message and send response
    ws.send(JSON.stringify({ status: 'received' }));
  });
});

// Native Messaging Host (save as com.example.local_agent.json)
{
  "name": "com.example.local_agent",
  "description": "Native messaging host for local agent",
  "path": "PATH_TO_YOUR_HOST_SCRIPT",
  "type": "stdio",
  "allowed_origins": [
    "chrome-extension://YOUR_EXTENSION_ID/"
  ]
}