kemal/docs/middlewares.md

Middlewares

Built-in Middlewares

Kemal has built-in middlewares for common use cases.

HTTP Basic Authorization

This middleware lets you add HTTP Basic Authorization to your Kemal application. You can easily use this middleware with basic_auth macro like below.

require "kemal"

basic_auth "username", "password"

get "/" do
  "This won't render without correct username and password."
end

Custom middlewares

You can create your own middleware by inheriting from HTTP::Handler

class CustomHandler < HTTP::Handler
  def call(request)
    puts "Doing some custom stuff here"
    call_next request
  end
end

Kemal.config.add_handler CustomHandler.new