module ActionController
class RedirectBackError < AbstractController::Error #:nodoc:
DEFAULT_MESSAGE = 'No HTTP_REFERER was set in the request to this action, so redirect_to :back could not be called successfully. If this is a test, make sure to specify request.env["HTTP_REFERER"].'
def initialize(message = nil)
super(message || DEFAULT_MESSAGE)
end
end
module Redirecting
extend ActiveSupport::Concern
include AbstractController::Logger
include ActionController::RackDelegation
include ActionController::UrlFor
# Redirects the browser to the target specified in +options+. This parameter can take one of three forms:
#
# * <tt>Hash</tt> - The URL will be generated by calling url_for with the +options+.
# * <tt>Record</tt> - The URL will be generated by calling url_for with the +options+, which will reference a named URL for that record.
# * <tt>String</tt> starting with <tt>protocol://</tt> (like <tt>http://</tt>) or a protocol relative reference (like <tt>//</tt>) - Is passed straight through as the target for redirection.
# * <tt>String</tt> not containing a protocol - The current protocol and host is prepended to the string.
# * <tt>Proc</tt> - A block that will be executed in the controller's context. Should return any option accepted by +redirect_to+.
# * <tt>:back</tt> - Back to the page that issued the request. Useful for forms that are triggered from multiple places.
# Short-hand for <tt>redirect_to(request.env["HTTP_REFERER"])</tt>
#
# redirect_to action: "show", id: 5
# redirect_to post
# redirect_to "http://www.rubyonrails.org"
# redirect_to "/images/screenshot.jpg"
# redirect_to articles_url
# redirect_to :back
# redirect_to proc { edit_post_url(@post) }
#
# The redirection happens as a "302 Found" header unless otherwise specified.
#
# redirect_to post_url(@post), status: :found
# redirect_to action: 'atom', status: :moved_permanently
# redirect_to post_url(@post), status: 301
# redirect_to action: 'atom', status: 302
#
# The status code can either be a standard {HTTP Status code}[http://www.iana.org/assignments/http-status-codes] as an
# integer, or a symbol representing the downcased, underscored and symbolized description.
# Note that the status code must be a 3xx HTTP code, or redirection will not occur.
#
# If you are using XHR requests other than GET or POST and redirecting after the
# request then some browsers will follow the redirect using the original request
# method. This may lead to undesirable behavior such as a double DELETE. To work
# around this you can return a <tt>303 See Other</tt> status code which will be
# followed using a GET request.
#
# redirect_to posts_url, status: :see_other
# redirect_to action: 'index', status: 303
#
# It is also possible to assign a flash message as part of the redirection. There are two special accessors for the commonly used flash names
# +alert+ and +notice+ as well as a general purpose +flash+ bucket.
#
# redirect_to post_url(@post), alert: "Watch it, mister!"
# redirect_to post_url(@post), status: :found, notice: "Pay attention to the road"
# redirect_to post_url(@post), status: 301, flash: { updated_post_id: @post.id }
# redirect_to { action: 'atom' }, alert: "Something serious happened"
#
# When using <tt>redirect_to :back</tt>, if there is no referrer, ActionController::RedirectBackError will be raised. You may specify some fallback
# behavior for this case by rescuing ActionController::RedirectBackError.
def redirect_to(options = {}, response_status = {}) #:doc:
raise ActionControllerError.new("Cannot redirect to nil!") unless options
raise AbstractController::DoubleRenderError if response_body
logger.debug { "Redirected by #{caller(1).first rescue "unknown"}" } if logger
self.status = _extract_redirect_to_status(options, response_status)
self.location = _compute_redirect_to_location(options)
self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.h(location)}\">redirected</a>.</body></html>"
end
private
def _extract_redirect_to_status(options, response_status)
if options.is_a?(Hash) && options.key?(:status)
Rack::Utils.status_code(options.delete(:status))
elsif response_status.key?(:status)
Rack::Utils.status_code(response_status[:status])
else
302
end
end
def _compute_redirect_to_location(options)
case options
# The scheme name consist of a letter followed by any combination of
# letters, digits, and the plus ("+"), period ("."), or hyphen ("-")
# characters; and is terminated by a colon (":").
# The protocol relative scheme starts with a double slash "//"
when %r{^(\w[\w+.-]*:|//).*}
options
when String
request.protocol + request.host_with_port + options
when :back
request.headers["Referer"] or raise RedirectBackError
when Proc
_compute_redirect_to_location options.call
else
url_for(options)
end.delete("\0\r\n")
end
end
end