Methods
H
Instance Public methods
head(status, options = {})

Return a response that has no content (merely headers). The options argument is interpreted to be a hash of header names and values. This allows you to easily return a response that consists only of significant headers: 

  head :created, :location => person_path(@person)

  head :created, :location => @person

It can also be used to return exceptional conditions: 

  return head(:method_not_allowed) unless request.post?
  return head(:bad_request) unless valid_request?
  render

Source: show | on GitHub 

    # File actionpack/lib/action_controller/metal/head.rb, line 19
19:     def head(status, options = {})
20:       options, status = status, nil if status.is_a?(Hash)
21:       status ||= options.delete(:status) || :ok
22:       location = options.delete(:location)
23:       content_type = options.delete(:content_type)
24: 
25:       options.each do |key, value|
26:         headers[key.to_s.dasherize.split('-').each { |v| v[0] = v[0].chr.upcase }.join('-')] = value.to_s
27:       end
28: 
29:       self.status = status
30:       self.location = url_for(location) if location
31:       self.content_type = content_type || (Mime[formats.first] if formats)
32:       self.response_body = " "
33:     end