More experimental RESTful router implementation

fruit_collection_handler.ex

defmodule RESTRouter.FruitCollectionHandler do
  
  provides "application/json"
  provides "text/html"
  provides "text/plain"
  accepts  "application/json"

  defp fetch
    Fruit.to_sequence.reverse
  end
  
  def write fruit_tuple
    fruit = Fruit.last
    id =  if fruit do
            fruit.id + 1
          else
            1
          end
    fruit = Fruit[id: id, content: conn.params[:content]]
    fruit.write
    fruit
  end
end

fruit_object_handler.ex

defmodule RESTRouter.FruitObjectHandler do

  defp fetch
    Fruit.read conn.params[:fruit_id]
  end
  
  defp write fruit_id, fruit_tuple
    # Some code to modify an existing fruit
  end
  
  def delete
    # Some code to delete an existing fruit
  end
  
  provides "application/json" # Assumes default provide_json
  provides "text/html"        # Assumes default provide_html
  provides "text/plain"       # Assumes default provide_plain
  accepts  "application/json" # Assumes default accept_json
  
  def service_available
    # Some code...
  end
  
  def last_modified
    # Some code...
  end
  
  # Other REST callbacks are supported as well.
end

fruit_object_handler_verbose.ex

defmodule RESTRouter.FruitObjectHandler do

  # [REQUIRED]
  defp fetch
    Fruit.read conn.params[:fruit_id]
  end
  
  # [OPTIONAL] required if any _accept_ callback is defined
  defp write fruit_id, fruit_tuple
    # Some code to modify an existing fruit
  end
  
  # [OPTIONAL] required if delete method is accepted
  def delete
    # Some code to delete an existing fruit
  end
  
  provides "application/json" # Assumes default provide_json
  provides "text/html"        # Assumes default provide_html
  provides "text/plain"       # Assumes default provide_plain
  accepts  "application/json" # Assumes default accept_json
  
  # [OPTIONAL] default is method below.
  def provide_json
    fetch |> Jiffy.encode |> conn.resp_body
  end
  
  # [OPTIONAL] default is method below.
  def provide_html
    conn.assign :collection, fetch
    render conn, "fruit_object.html"
  end
  
  # [OPTIONAL] default is method below.
  def provide_plain
    conn.assign :collection, fetch
    render conn, "fruit_object.txt"
  end
  
  # [OPTIONAL] default is method below.
  def accept_json
    Jiffy.decode conn.sent_body |> write
  end

  # [OPTIONAL] default values below
  allowed_methods ["GET", "PUT", "DELETE", "OPTIONS"]

  # [OPTIONAL] default value: true
  def service_available
    # Some code...
  end
  
  # [OPTIONAL] default value: nil
  def last_modified
    # Some code...
  end
  
  # Other REST callbacks are supported as well.
end

rest_router.ex

defmodule RESTRouter do
  use Dynamo
  use Dynamo.Router
  
  prepare do
    conn.fetch [:params, :cookies]
  end
  
  config :server, port: 3030
  
  # New resource macro for simple restful handlers
  resource :fruit do
    # Automatically creates routes
    # /fruit            <- for collections
    # /fruit/:fruit_id  <- for objects
    # 
    # Assumes default handler names:
    #   RESTRouter.FruitCollectionHandler & RESTRouter.FruitObjectHandler
  end
end