Constants
ILLEGAL_HEADER_VALUE_REGEX | = | /[\x00-\x08\x0A-\x1F]/ |
Instance Public methods
redirect_back(fallback_location:, allow_other_host: _allow_other_host, **args) Link
Soft deprecated alias for redirect_back_or_to
where the fallback_location
location is supplied as a keyword argument instead of the first positional argument.
redirect_back_or_to(fallback_location, allow_other_host: _allow_other_host, **options) Link
Redirects the browser to the page that issued the request (the referrer) if possible, otherwise redirects to the provided default fallback location.
The referrer information is pulled from the HTTP Referer
(sic) header on the request. This is an optional header and its presence on the request is subject to browser security settings and user preferences. If the request is missing this header, the fallback_location
will be used.
redirect_back_or_to({ action: "show", id: 5 })
redirect_back_or_to @post
redirect_back_or_to "http://www.rubyonrails.org"
redirect_back_or_to "/images/screenshot.jpg"
redirect_back_or_to posts_url
redirect_back_or_to proc { edit_post_url(@post) }
redirect_back_or_to '/', allow_other_host: false
Options
-
:allow_other_host
- Allow or disallow redirection to the host that is different to the current host, defaults to true.
All other options that can be passed to redirect_to
are accepted as options, and the behavior is identical.
# File actionpack/lib/action_controller/metal/redirecting.rb, line 149 def redirect_back_or_to(fallback_location, allow_other_host: _allow_other_host, **options) if request.referer && (allow_other_host || _url_host_allowed?(request.referer)) redirect_to request.referer, allow_other_host: allow_other_host, **options else # The method level `allow_other_host` doesn't apply in the fallback case, omit # and let the `redirect_to` handling take over. redirect_to fallback_location, **options end end
redirect_to(options = {}, response_options = {}) Link
Redirects the browser to the target specified in options
. This parameter can be any one of:
-
Hash
- The URL will be generated by calling url_for with theoptions
. -
Record
- The URL will be generated by calling url_for with theoptions
, which will reference a named URL for that record. -
String
starting withprotocol://
(likehttp://
) or a protocol relative reference (like//
) - Is passed straight through as the target for redirection. -
String
not containing a protocol - The current protocol and host is prepended to the string. -
Proc
- A block that will be executed in the controller’s context. Should return any option accepted byredirect_to
.
Examples
redirect_to action: "show", id: 5
redirect_to @post
redirect_to "http://www.rubyonrails.org"
redirect_to "/images/screenshot.jpg"
redirect_to posts_url
redirect_to proc { edit_post_url(@post) }
The redirection happens as a 302 Found
header unless otherwise specified using the :status
option:
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 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 303 See Other
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")
Statements after redirect_to
in our controller get executed, so redirect_to
doesn’t stop the execution of the function. To terminate the execution of the function immediately after the redirect_to
, use return.
redirect_to post_url(@post) and return
Open Redirect protection
By default, Rails
protects against redirecting to external hosts for your app’s safety, so called open redirects. Note: this was a new default in Rails
7.0, after upgrading opt-in by uncommenting the line with raise_on_open_redirects
in config/initializers/new_framework_defaults_7_0.rb
Here redirect_to
automatically validates the potentially-unsafe URL:
redirect_to params[:redirect_url]
Raises UnsafeRedirectError
in the case of an unsafe redirect.
To allow any external redirects pass allow_other_host: true
, though using a user-provided param in that case is unsafe.
redirect_to "https://rubyonrails.org", allow_other_host: true
See url_from
for more information on what an internal and safe URL is, or how to fall back to an alternate redirect URL in the unsafe case.
# File actionpack/lib/action_controller/metal/redirecting.rb, line 103 def redirect_to(options = {}, response_options = {}) raise ActionControllerError.new("Cannot redirect to nil!") unless options raise AbstractController::DoubleRenderError if response_body allow_other_host = response_options.delete(:allow_other_host) { _allow_other_host } proposed_status = _extract_redirect_to_status(options, response_options) redirect_to_location = _compute_redirect_to_location(request, options) _ensure_url_is_http_header_safe(redirect_to_location) self.location = _enforce_open_redirect_protection(redirect_to_location, allow_other_host: allow_other_host) self.response_body = "" self.status = proposed_status end
url_from(location) Link
Verifies the passed location
is an internal URL that’s safe to redirect to and returns it, or nil if not. Useful to wrap a params provided redirect URL and fall back to an alternate URL to redirect to:
redirect_to url_from(params[:redirect_url]) || root_url
The location
is considered internal, and safe, if it’s on the same host as request.host
:
# If request.host is example.com:
url_from("https://example.com/profile") # => "https://example.com/profile"
url_from("http://example.com/profile") # => "http://example.com/profile"
url_from("http://evil.com/profile") # => nil
Subdomains are considered part of the host:
# If request.host is on https://example.com or https://app.example.com, you'd get:
url_from("https://dev.example.com/profile") # => nil
NOTE: there’s a similarity with url_for, which generates an internal URL from various options from within the app, e.g. url_for(@post)
. However, url_from
is meant to take an external parameter to verify as in url_from(params[:redirect_url])
.