API Reference

handleUndefinedResponsesMiddleware

import {handleUndefinedResponsesMiddleware} from 'papupata'

Availability

This functionality is available from papupata version 1.5.0 onwards.

Purpose

Middleware that changes how papupata deals with undefined responses, automatically setting up response code 204 (if not otherwise specified) and sending a response.

Usage

By default papupata assumes that if your route implementation returns undefined, it takes the responsibilities for sending the response.

This if often not the case, though. You might have APIs that do things but do not return anything, in which case it makes sense for the response to be undefined or void. But what it means by default is that you have either do something like

res.status(204); res.end()

or return an empty string.

This middleware changes things in two ways; one: if headers have not been sent by the time the route implementation returns undefined, an empty response is automatically sent. Also, in that case, if the response status code has not been explicitly set, it becomes 204 (no content).

The behaviour of this middleware might become the default mode of operation for papupata 2.0.

Examples

Enabling middleware for all roues

const API = new APIDeclaration()
API.configure({
  // other options
  inherentMiddleware: [handleUndefinedResponsesMiddleware]
})

Enabling the middleware for a single route

const api = API.declareGetAPI('/test').response<string>()
api.implementWithPapupataMiddleware([handleUndefinedResponsesMiddleware], () => skipHandlingRoute)

Expected effect: simple case

api.implement(async () => {
  await doStuff()
})
// Without middleware there is never a response; with the middleware the response is a 204

Expected effect: explicit status

api.implement(async (_req, res) => {
  res.status(500)
  await doStuff()
})
// Without middleware there is never a response; with the middleware the response is a 500

Expected effect: redirect

api.implement(async (_req, res) => {
  res.redirect('/')
})
// Works with and without middleware

Table of contents