method

head

v1.2.6 - Show latest stable - 2 notes - Class: ActionController::Base

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What's this?

head(*args) protected

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)

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

Show source

# File actionpack/lib/action_controller/base.rb, line 885
      def head(*args)
        if args.length > 2
          raise ArgumentError, "too many arguments to head"
        elsif args.empty?
          raise ArgumentError, "too few arguments to head"
        elsif args.length == 2
          status = args.shift
          options = args.shift
        elsif args.first.is_a?(Hash)
          options = args.first
        else
          status = args.first
          options = {}
        end

        raise ArgumentError, "head requires an options hash" if !options.is_a?(Hash)

        status = interpret_status(status || options.delete(:status) || :ok)

        options.each do |key, value|
          headers[key.to_s.dasherize.split(/-/).map { |v| v.capitalize }.join("-")] = value.to_s
        end

        render :nothing => true, :status => status
      end

July 7, 2008

5 thanks

List of statuses

You can view a full list of statuses at http://dev.rubyonrails.org/browser/trunk/actionpack/lib/action_controller/status_codes.rb.

head can be called with a symbol or a status code:

Using head with a symbol

head :length_required # 411 Length Required
head :ok              # 200 OK

Using head with a status code

head 404              # 404 Not Found

November 26, 2013

0 thanks

Updated list of statuses

The list of supported statuses is now in the layout & rendering rails guide:

http://guides.rubyonrails.org/layouts_and_rendering.html#the-status-option

head

Related methods

List of statuses

Using head with a symbol

Using head with a status code

Updated list of statuses