def call(env)
      req = Rack::Request.new(env)

      [200, { 'Content-Type' => 'application/json' }, [dispatch_action(req)]]
    rescue Heartcheck::Errors::RoutingError
      [404, { 'Content-Type' => 'application/json' }, ['Not found']]
    end
def call(env)
      req = Rack::Request.new(env)

      [200, { 'Content-Type' => 'application/json' }, [dispatch_action(req)]]
    rescue Heartcheck::Errors::RoutingError
      [404, { 'Content-Type' => 'application/json' }, ['Not found']]
    end
Sets up the rack application.

 @param app [RackApp] is a rack app where
   heartcheck is included.

 @return [void]
 Sets up the rack application.

 @param env [Hash] is an instance of Hash
   that includes CGI-like headers.

 @return [Array] must be an array that contains
   - The HTTP response code
   - A Hash of headers
   - The response body, which must respond to each