V2.2: Rack integration

Rack environment

Actions offer a high level API built on top of Rack. To access the raw data from the Rack environment within an action, use request.env.

module Bookshelf
  module Actions
    module Books
      class Show < Bookshelf::Action
        def handle(request, response)
          request.env

          request.env["REQUEST_METHOD"] #=> GET
          request.env["PATH_INFO"] #=> /books/1
        end
      end
    end
  end
end

Rack middleware

Hanami mounts a thin default middleware stack. Additional middleware can be mounted either at application level, in the router, or for an individual action.

Inspecting the middleware stack

Use the hanami middleware command to inspect the Rack middleware stack.

$ bundle exec hanami middleware

/    Dry::Monitor::Rack::Middleware (instance)

Application-level middleware

To add middleware at an application level, use the middleware config on your app:

# config/app.rb

module Bookshelf
  class App < Hanami::App
    config.middleware.use Rack::Auth::Basic
  end
end

$ bundle exec hanami middleware

/    Dry::Monitor::Rack::Middleware (instance)
/    Rack::Auth::Basic

Middleware will be included in the stack in the order in which it’s added.

# config/app.rb

module Bookshelf
  class App < Hanami::App
    config.middleware.use Rack::Auth::Basic
    config.middleware.use Rack::MethodOverride
  end
end

$  bundle exec hanami middleware

/    Dry::Monitor::Rack::Middleware (instance)
/    Rack::Auth::Basic
/    Rack::MethodOverride

If needed, you can use before: or after: to insert a middleware at a particular point in the stack:

# config/app.rb

module Bookshelf
  class App < Hanami::App
    config.middleware.use Rack::Auth::Basic
    config.middleware.use Rack::MethodOverride
    config.middleware.use Rack::ShowStatus, before: Rack::Auth::Basic
  end
end

$  bundle exec hanami middleware

/    Dry::Monitor::Rack::Middleware (instance)
/    Rack::ShowStatus
/    Rack::Auth::Basic
/    Rack::MethodOverride

Router middleware

Middleware can also be added via your routes configuration in config/routes.rb. Middleware added here is added after any middleware added via app config.

# config/routes.rb

module Bookshelf
  class Routes < Hanami::Routes
    use Rack::Runtime

    root { "Hello from Hanami" }
  end
end

Adding middleware via your routes config lets you add middleware to specific routes.

# config/routes.rb

module Bookshelf
  class Routes < Hanami::Routes
    use Rack::Runtime

    root { "Hello from Hanami" }

    scope "restricted" do
      use Rack::Auth::Basic

      get "/page" do
        "Some restricted content"
      end
    end

    slice :admin, at: "/admin" do
      use Rack::Auth::Basic

      get "/books", to: "books.index"
    end
  end
end

$ bundle exec hanami middleware

/              Dry::Monitor::Rack::Middleware (instance)
/              Rack::Runtime
/restricted    Rack::Auth::Basic
/admin         Rack::Auth::Basic

Using config.ru

Middleware can also be implemented in config.ru. This middleware will not be part of the Hanami application’s middleware stack.

# config.ru

require "hanami/boot"

use Rack::Static, :urls => ["/public"]

run Hanami.app