Introduction

This is a hybrid Next.js + Python app that uses Next.js as the frontend and FastAPI with Socket.IO as the API backend. One great use case of this is to write Next.js apps that use websocket comunication.

How It Works

The Python/FastAPI server is mapped into to Next.js app under /api/.

This is implemented using next.config.js rewrites to map any request to /api/:path* to the FastAPI app, which is hosted in the /api folder.

On localhost, the rewrite will be made to the 127.0.0.1:8000 port, which is where the Uvicorn server is running.

In production, the FastAPI server is hosted in the same dyno as the Next.js app, so works in a similar way.

Deploy Your Own

You can clone & deploy it to Heroku with one click:

Developing Locally

You can clone & create this repo with the following command

npx create-next-app nextjs-fastapi-socketio --example "https://github.com/imcarlosguerrero/nextjs-fastapi-socketio-template"

Getting Started

First, install the dependencies:

npm install
# or
yarn
# or
pnpm install
# or
bun install

Then, run the development server:

npm run dev
# or
yarn dev
# or
pnpm dev
# or
bun dev

Open http://localhost:3000 with your browser to see the result.

The FastAPI server will be running on http://127.0.0.1:8000 – feel free to change the port in package.json (you'll also need to update it in next.config.js).

Why the template doesn't use Vercel

Vercel is based in a serverless approach that doesn't support websockets, therefore, the deployment of a project using this template wouldn't work at all.

Learn More

To learn more about Next.js and the technologies used in this template, take a look at the following resources:

• Next.js Documentation - learn about Next.js features and API.
• Learn Next.js - an interactive Next.js tutorial.
• FastAPI Documentation - learn about FastAPI features and API.
• Socket.IO Documentation - learn about Socket.IO features and API.
• About Vercel and WebSockets - learn more about Vercel and WebSockets.