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HTTP server


Requires @compas/stdlib and @compas/server to be installed

Compas also provides some utilities for constructing an HTTP server. This is based on Koa. The server consist of built-in error handling, a logger and security headers.

Default server

Create a file at scripts/api.js with the following contents:

import { getApp } from "@compas/server";
import { mainFn } from "@compas/stdlib";

mainFn(import.meta, main);

async function main() {
  const app = getApp({});


When we run this file we can already check out some default features.

compas run api
# Or
node ./scripts/api.js

We are going to do some GET requests, you can use your browser or another HTTP client, like httpie .

  1. Check if the server is running
http GET http://localhost:3000/_health
  1. 404 handling
http GET http://localhost:3000/oops
  1. Logging

Check the logs of the running server. You should see quite a bit of output there. Notice that the /_health request is missing. In order, you should see the following:

  • Formatted 404 error with stack trace. This is an 'info' log for any non 500 response status error.
  • The request log to /oops, containing some request and response information.
  • Event callstack, this can be used for timings, analytics or other diagnostic purposes.

Notes that all logs also contain a requestId. This is automatically added when you use the logger provided by ctx.log. The context also contains ctx.event. These two together are explained in logger and events

Other middleware

  • createBodyParser can be used to create a middleware that is able to parse json or multipart bodies.
  • compose can be used to manually compose multiple middleware in to a single callable middleware
  • sendFile is a utility to easily send out files. Supports partial responses, when for example sending a video.