macOS support

1

Start backend

Start your backend server on port 8000:

npm run dev

python main.py

go run .

rails server -p 8000

2

Start Subtrace

In a second terminal window, install Subtrace and start the proxy:

curl -fsSL https://subtrace.dev/install.sh | sh

# starts listening on 9000 and proxies requests to 8000
subtrace proxy 9000:8000

Show example output

3

Update frontend

Configure your frontend to send all backend requests to localhost:9000 instead:

const API_URL = 'http://localhost:8000'
const API_URL = 'http://localhost:9000'

fetch(`${API_URL}/api/users`)
  .then(res => res.json())
  .then(data => setUsers(data))

const API_URL = 'http://localhost:8000'
const API_URL = 'http://localhost:9000'

export async function getServerSideProps() {
  const res = await fetch(`${API_URL}/api/data`)
  const data = await res.json()
  return { props: { data } }
}

const API_URL = 'http://localhost:8000'
const API_URL = 'http://localhost:9000'

axios.get(`${API_URL}/api/items`)
  .then(response => {
    this.items = response.data
  })

private apiUrl = 'http://localhost:8000'; 
private apiUrl = 'http://localhost:9000'; 

getProducts(): Observable<Product[]> {
  return this.http.get<Product[]>(`${this.apiUrl}/api/products`);
}

// vite.config.js
export default {
  server: {
    proxy: {
      '/api': 'http://localhost:8000'
      '/api': 'http://localhost:9000'
    }
  }
}

// webpack.config.js
module.exports = {
  devServer: {
    proxy: {
      '/api': 'http://localhost:8000'
      '/api': 'http://localhost:9000'
    }
  }
}

4

See requests

Open the subt.link URL in your browser to watch every request happening in realtime:

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