Kemal Web Framework Documentation

To get started with Kemal, ensure you have Crystal installed. Follow these steps to create a new application:

1. Initialize a new Crystal app:

   crystal init app my-kemal-app
   cd my-kemal-app

2. Add kemal to your shard.yml dependencies:

   dependencies:
     kemal:
       github: kemalcr/kemal

3. Install dependencies and run the application:

   shards install
   crystal run src/my_kemal_app.cr

Kemal provides a simple DSL for defining routes, handling JSON responses, and managing WebSocket connections.

• Use get, post, put, patch, and delete for standard HTTP verbs.
• Access the environment object (env) in route blocks to manipulate responses, such as setting the content_type.
• Use ws to define WebSocket endpoints.
• Call Kemal.run to start the server.

require "kemal"

# Basic route - responds to GET "http://localhost:3000/"
get "/" do
  "Hello World!"
end

# JSON API example
get "/api/status" do |env|
  env.response.content_type = "application/json"
  {"status": "ok"}.to_json
end

# WebSocket support
ws "/chat" do |socket|
  socket.send "Hello from Kemal WebSocket!"
end

Kemal.run