Rack::Params

# NOTE (to self) - if this changes, update `readme_spec.rb`

class SomeExampleApp
  include Rack::Params

  # create named validators that can be run at any time
  
  validator :document do
    param :id,      Integer,  required: true
    param :title,   String,   required: true
    param :created, DateTime
    
    param :tags, Array do
      every :symbol
    end
    
    param :content, Hash, required: true do
      param :header, String
      param :body,   String, required: true
    end
  end
  
  # run pre-defined or ad-hoc transforms on some hash
  # only keys in the validator blocks are copied, see #splat

  def call(env)
    request = Rack::Request.new(env)
    
    params = request.params
    params = validate(request.params, :document)
    if params.valid?
      assert params["id"].is_a? Integer
      assert (not params["content"]["body"].nil?)
    else
      assert params.errors.length > 0
      assert params.invalid?
    end

    # or
    params = { "flag" => "f", "some" => "other key", "and" => "one more" }
    params = validate(params) do
      param :flag,  :boolean, required: true
      splat :rest
    end
    
    if params.valid?
      assert [true, false].include?(params["flag"])
      assert (["some", "and"] - params["rest"]).empty?
    end

  end
end

# if you're using a framework which provides `request` as a getter method
# include the connector, which provides a `#params` override, and allows
# defaulting to request.params in validate calls

class FancyApp < Nancy::Base
  include Rack::Params::Connect

  validator :check do
    :id, Integer
  end
  
  get "/" do
    validate :check

    if params.valid?
      assert params["id"].is_a? Integer
    else
      assert params.errors.length > 0
      assert params.invalid?
    end
    
    "magic 8-ball, how's my params? << uncertan. >>"
  end

  get "/blow-up-on-failure" do
    validate! :check
    assert params.valid?

    "if I'm going down, I'm taking you all with me."
  end
end

gem 'rack-params'