@browser-echo/react

React component for streaming browser console logs to your dev terminal (non-Vite setups).

💡 Using React with Vite? Check out our React + Vite setup guide for the recommended approach using @browser-echo/vite.

This package provides a React provider component for non-Vite environments. If you're using Vite, prefer @browser-echo/vite which includes the dev middleware automatically.

Table of Contents

• Installation
• Usage
• Configuration
• Install MCP Server

Features

• React provider component
• Client-side console patching
• Configurable log levels and batching
• Works with any React setup (non-Vite)
• No production impact

When to use this package

• ✅ React projects not using Vite
• ✅ Custom bundler setups
• ✅ When you want manual control over initialization

When NOT to use this package

• ❌ React + Vite projects (use @browser-echo/vite instead)
• ❌ Next.js projects (use @browser-echo/next instead)

Installation

npm install -D @browser-echo/react @browser-echo/core
# or
pnpm add -D @browser-echo/react @browser-echo/core

Setup

1. Add the provider component

Mount the provider in your app root (development only):

// src/main.tsx
import React from 'react';
import ReactDOM from 'react-dom/client';
import { BrowserEchoProvider } from '@browser-echo/react';
import App from './App';

function Root() {
  return (
    <>
      {process.env.NODE_ENV === 'development' && <BrowserEchoProvider />}
      <App />
    </>
  );
}

ReactDOM.createRoot(document.getElementById('root')!).render(<Root />);

2. Create a server endpoint

You need a development server endpoint that accepts POST requests at /__client-logs and prints the received logs to your terminal. The React provider only handles the client side.

Note: Network capture (fetch/XHR/WS) is available via @browser-echo/core and framework providers (Vite, Next, Nuxt). This React (non-Vite) package does not inject network capture on its own. If you use initBrowserEcho directly, you can also enable network body snippets via core options:

initBrowserEcho({
  route: '/__client-logs',
  networkLogs: {
    enabled: true,
    bodies: {
      request: true,
      response: true,
      maxBytes: 2048,
      allowContentTypes: ['application/json','text/','application/x-www-form-urlencoded'],
      prettyJson: true
    }
  }
});

Example Express.js endpoint:

// dev-server.js
app.post('/__client-logs', express.json(), (req, res) => {
  const { sessionId, entries } = req.body;
  
  entries.forEach(entry => {
    const timestamp = new Date(entry.time).toISOString();
    const level = entry.level.toUpperCase();
    console.log(`[browser] [${sessionId}] ${level}: ${entry.text}`);
    if (entry.stack) {
      console.log(entry.stack);
    }
  });
  
  res.status(200).end();
});

Configuration

Customize the provider with props:

<BrowserEchoProvider 
  route="/__client-logs"
  include={['warn', 'error']}
  preserveConsole={true}
  tag="[browser]"
  batch={{ size: 20, interval: 300 }}
  stackMode="condensed"
/>

Available Props

interface BrowserEchoProviderProps {
  route?: `/${string}`;              // default: '/__client-logs'
  include?: BrowserLogLevel[];       // default: ['log','info','warn','error','debug']
  preserveConsole?: boolean;         // default: true
  tag?: string;                      // default: '[browser]'
  batch?: { size?: number; interval?: number }; // default: 20 / 300ms
  stackMode?: 'full' | 'condensed' | 'none';    // default: 'condensed'
}

Complete Example

// src/main.tsx
import React from 'react';
import ReactDOM from 'react-dom/client';
import { BrowserEchoProvider } from '@browser-echo/react';
import App from './App';

function Root() {
  return (
    <>
      {process.env.NODE_ENV === 'development' && (
        <BrowserEchoProvider 
          route="/api/dev-logs"
          include={['warn', 'error']}
          stackMode="condensed"
          tag="[react-app]"
        />
      )}
      <App />
    </>
  );
}

ReactDOM.createRoot(document.getElementById('root')!).render(<Root />);

Alternative: Direct Usage

If you prefer not to use the React component, you can use the core library directly:

// src/main.tsx
import { initBrowserEcho } from '@browser-echo/core';

if (process.env.NODE_ENV === 'development') {
  initBrowserEcho({
    route: '/__client-logs',
    include: ['warn', 'error'],
  });
}

Install MCP Server

For React (non-Vite) apps, MCP forwarding depends on your server-side route implementation. The React provider only handles browser-side log collection.

📖 First, set up the MCP server for your AI assistant, then configure framework options below.

Environment Variables

• BROWSER_ECHO_MCP_URL=http://127.0.0.1:5179/mcp — Set in your server environment
• BROWSER_ECHO_SUPPRESS_TERMINAL=1 — Control terminal output in your route handler

Server Route MCP Integration

Update your server route to forward to MCP:

// Example Express route with MCP forwarding
app.post('/__client-logs', async (req, res) => {
  const payload = req.body;
  
  // Forward to MCP if configured
  const mcpUrl = process.env.BROWSER_ECHO_MCP_URL;
  if (mcpUrl) {
    const ingestUrl = mcpUrl.replace('/mcp', '/__client-logs');
    try {
      await fetch(ingestUrl, {
        method: 'POST',
        headers: { 'content-type': 'application/json' },
        body: JSON.stringify(payload)
      });
      // Suppress terminal output when forwarding
      if (process.env.BROWSER_ECHO_SUPPRESS_TERMINAL !== '0') {
        return res.status(204).end();
      }
    } catch {}
  }
  
  // Local terminal output
  for (const entry of payload.entries) {
    console.log(`[browser] ${entry.level.toUpperCase()}: ${entry.text}`);
  }
  res.status(204).end();
});

Dependencies

This package depends on @browser-echo/core for the client-side functionality.

Comparison with Other Packages

| Package | Best for | Includes server | Auto-setup | |---------|----------|----------------|------------| | @browser-echo/vite | React + Vite | ✅ | ✅ | | @browser-echo/next | Next.js | ✅ | ✅ | | @browser-echo/react | React (non-Vite) | ❌ | ❌ |

Troubleshooting

• No logs appear: Ensure you have a server endpoint that handles POST requests at your specified route
• CORS errors: Make sure your dev server accepts requests from your app's origin
• Too many logs: Use include: ['warn', 'error'] to reduce noise

Author

Kevin Kern

License

MIT

Links

• Main Repository
• Documentation
• Core Package
• Vite Package (recommended for Vite users)