101 Switching Protocols

The server agrees to switch to a different protocol, like upgrading a standard HTTP connection to a continuous WebSocket connection.

When and Why to Use It

Use this when a client asks to open a WebSocket connection. Your server responds with 101 to confirm ‘Yes, we are no longer speaking standard HTTP, we are now using WebSockets’.

Usage Examples

Shokupan (Functional)

import { HttpCode, get } from 'shokupan';

export const getResource = get('/resource', () => {
    return { message: 'Switching Protocols' };
}).pipe(HttpCode(101));

Shokupan (Controller)

import { Controller, Get, HttpCode } from 'shokupan';

@Controller('/api')
export class ExampleController {
    @Get('/resource')
    @HttpCode(101)
    getResource() {
        return { message: 'Switching Protocols' };
    }
}

Express

import express from 'express';
const app = express();

app.get('/resource', (req, res) => {
    res.status(101).json({ message: 'Switching Protocols' });
});

Nest

import { Controller, Get, HttpCode } from '@nestjs/common';

@Controller('api')
export class ExampleController {
  @Get('resource')
  @HttpCode(101)
  getResource() {
    return { message: 'Switching Protocols' };
  }
}

Koa

import Koa from 'koa';
const app = new Koa();

app.use(async ctx => {
  if (ctx.path === '/resource' && ctx.method === 'GET') {
    ctx.status = 101;
    ctx.body = { message: 'Switching Protocols' };
  }
});