Super Simple <3

require "kemal"

get "/" do
  "Hello World!"
end

Build and run!

crystal build --release src/kemal_sample.cr
./kemal_sample

Go to http://localhost:3000

Check samples for more.

Installation

Add it to your shard.yml

dependencies:
  kemal:
    github: kemalcr/kemal
    branch: master

Routes

In Kemal, a route is an HTTP method paired with a URL-matching pattern. Each route is associated with a block:

  get "/" do
  .. show something ..
  end

  post "/" do
  .. create something ..
  end

  put "/" do
  .. replace something ..
  end

  patch "/" do
  .. modify something ..
  end

  delete "/" do
  .. annihilate something ..
  end

Context

Accessing the request environment (query params, body, headers e.g) is super easy. You can use the context returned from the block:

  # Matches /hello/kemal
  get "/hello/:name" do |env|
    name = env.params["name"]
    "Hello back to #{name}"
  end

  # Matches /resize?width=200&height=200
  get "/resize" do |env|
    width = env.params["width"]
    height = env.params["height"]
  end

Content Type

Kemal uses text/html as the default content type. You can change it via the context.

  # Set the content as application/json and return JSON
  get "/user.json" do |env|
    kemal = {name: "Kemal", language: "Crystal"}
    env.set_content_type "application/json"
    kemal.to_json
  end

Thanks

Thanks to Manas for their awesome work on Frank.

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