module ActionController::ParamsWrapper::ClassMethods

def _set_wrapper_options(options)
  self._wrapper_options = Options.from_hash(options)
end

module is inherited.
wrapper key and attribute names. Called automatically when the
Sets the default wrapper key or model which will be used to determine

def inherited(klass)
  if klass._wrapper_options.format.any?
    params = klass._wrapper_options.dup
    params.klass = klass
    klass._wrapper_options = params
  end
  super
end

will exclude from a nested hash.
* :exclude - The list of attribute names which parameters wrapper
will wrap into a nested hash.
* :include - The list of attribute names which parameters wrapper
will be enabled.
* :format - The list of formats in which the parameters wrapper
==== Options

# disables parameters wrapping for this controller altogether.
wrap_parameters false

# wraps only +:username+ and +:title+ attributes from parameters.
wrap_parameters include: [:username, :title]

# (+person+, in this case) and the list of attribute names
# wraps parameters by determining the wrapper key from Person class
wrap_parameters Person

# wraps parameters into +params[:person]+ hash
wrap_parameters :person

# enables the parameter wrapper for XML format
wrap_parameters format: :xml
==== Examples

would use to determine the attribute names from.
Sets the name of the wrapper key, or the model which +ParamsWrapper+

def wrap_parameters(name_or_model_or_options, options = {})
  model = nil
  case name_or_model_or_options
  when Hash
    options = name_or_model_or_options
  when false
    options = options.merge(format: [])
  when Symbol, String
    options = options.merge(name: name_or_model_or_options)
  else
    model = name_or_model_or_options
  end
  opts = Options.from_hash _wrapper_options.to_h.slice(:format).merge(options)
  opts.model = model
  opts.klass = self
  self._wrapper_options = opts
end