506 Variant Also Negotiates

A server configuration error resulting in an infinite loop while trying to negotiate the right content to return.

When and Why to Use It

Use this if your server gets stuck in a recursive loop trying to negotiate which content structure (like language or encoding format) to respond with.

Usage Examples

Shokupan (Functional)

import { HttpException, get } from 'shokupan';

export const getResource = get('/resource', () => {
    throw new HttpException('Variant Also Negotiates', 506);
});

Shokupan (Controller)

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

@Controller('/api')
export class ExampleController {
    @Get('/resource')
    getResource() {
        throw new HttpException('Variant Also Negotiates', 506);
    }
}

Express

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

app.get('/resource', (req, res) => {
    res.status(506).json({ error: 'Variant Also Negotiates' });
});

Nest

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

@Controller('api')
export class ExampleController {
  @Get('resource')
  getResource() {
    throw new HttpException('Variant Also Negotiates', 506);
  }
}

Koa

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

app.use(async ctx => {
  if (ctx.path === '/resource' && ctx.method === 'GET') {
    ctx.status = 506;
    ctx.body = { error: 'Variant Also Negotiates' };
  }
});