417 Expectation Failed

The server cannot meet the requirements specified in the client’s ‘Expect’ header.

When and Why to Use It

Use this when you reject a client’s 100-Continue expectation because you don’t support it or can’t fulfill it.

Usage Examples

Shokupan (Functional)

import { HttpException, get } from 'shokupan';

export const getResource = get('/resource', () => {
    throw new HttpException('Expectation Failed', 417);
});

Shokupan (Controller)

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

@Controller('/api')
export class ExampleController {
    @Get('/resource')
    getResource() {
        throw new HttpException('Expectation Failed', 417);
    }
}

Express

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

app.get('/resource', (req, res) => {
    res.status(417).json({ error: 'Expectation Failed' });
});

Nest

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

@Controller('api')
export class ExampleController {
  @Get('resource')
  getResource() {
    throw new HttpException('Expectation Failed', 417);
  }
}

Koa

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

app.use(async ctx => {
  if (ctx.path === '/resource' && ctx.method === 'GET') {
    ctx.status = 417;
    ctx.body = { error: 'Expectation Failed' };
  }
});