actionpack/lib/action_controller/metal/request_forgery_protection.rb
# Turn on request forgery protection. Bear in mind that GET and HEAD requests are not checked.
#
#   class ApplicationController < ActionController::Base
#     protect_from_forgery
#   end
#
#   class FooController < ApplicationController
#     protect_from_forgery except: :index
#   end
#
# You can disable forgery protection on controller by skipping the verification before_action:
#
#   skip_before_action :verify_authenticity_token
#
# Valid Options:
#
# * <tt>:only</tt> / <tt>:except</tt> - Only apply forgery protection to a subset of actions. For example <tt>only: [ :create, :create_all ]</tt>.
# * <tt>:if</tt> / <tt>:unless</tt> - Turn off the forgery protection entirely depending on the passed Proc or method reference.
# * <tt>:prepend</tt> - By default, the verification of the authentication token will be added at the position of the
#   protect_from_forgery call in your application. This means any callbacks added before are run first. This is useful
#   when you want your forgery protection to depend on other callbacks, like authentication methods (Oauth vs Cookie auth).
#
#   If you need to add verification to the beginning of the callback chain, use <tt>prepend: true</tt>.
# * <tt>:with</tt> - Set the method to handle unverified request.
#
# Built-in unverified request handling methods are:
# * <tt>:exception</tt> - Raises ActionController::InvalidAuthenticityToken exception.
# * <tt>:reset_session</tt> - Resets the session.
# * <tt>:null_session</tt> - Provides an empty session during request but doesn't reset it completely. Used as default if <tt>:with</tt> option is not specified.
#
# You can also implement custom strategy classes for unverified request handling:
#
#    class CustomStrategy
#      def initialize(controller)
#        @controller = controller
#      end
#
#      def handle_unverified_request
#        # Custom behavior for unverfied request
#      end
#    end
#
#    class ApplicationController < ActionController:x:Base
#      protect_from_forgery with: CustomStrategy
#    end
# * <tt>:store</tt> - Set the strategy to store and retrieve CSRF tokens.
#
# Built-in session token strategies are:
# * <tt>:session</tt> - Store the CSRF token in the session.  Used as default if <tt>:store</tt> option is not specified.
# * <tt>:cookie</tt> - Store the CSRF token in an encrypted cookie.
#
# You can also implement custom strategy classes for CSRF token storage:
#
#   class CustomStore
#     def fetch(request)
#       # Return the token from a custom location
#     end
#
#     def store(request, csrf_token)
#       # Store the token in a custom location
#     end
#
#     def reset(request)
#       # Delete the stored session token
#     end
#   end
#
#   class ApplicationController < ActionController:x:Base
#     protect_from_forgery store: CustomStore.new
#   end
Turn on request forgery protection. Bear in mind that GET and HEAD requests are not checked.



You can disable forgery protection on controller by skipping the verification before_action.



Valid Options.

:only / :except - Only apply forgery protection to a subset of actions. For example only: [ :create, :create_all ].
:if / :unless - Turn off the forgery protection entirely depending on the passed Proc or method reference.
:prepend - By default, the verification of the authentication token will be added at the position of the
protect_from_forgery call in your application. This means any callbacks added before are run first. This is useful
when you want your forgery protection to depend on other callbacks, like authentication methods (Oauth vs Cookie auth).

If you need to add verification to the beginning of the callback chain, use prepend: true.
:with - Set the method to handle unverified request.

Built-in unverified request handling methods are:
:exception - Raises ActionController::InvalidAuthenticityToken exception.
:reset_session - Resets the session.
:null_session - Provides an empty session during request but doesn't reset it completely. Used as default if :with option is not specified.

You can also implement custom strategy classes for unverified request handling.



def handle_unverified_request
Custom behavior for unverfied request
end
end

class ApplicationController < ActionController:x:Base
protect_from_forgery with: CustomStrategy
end
:store - Set the strategy to store and retrieve CSRF tokens.

Built-in session token strategies are:
:session - Store the CSRF token in the session.  Used as default if :store option is not specified.
:cookie - Store the CSRF token in an encrypted cookie.

You can also implement custom strategy classes for CSRF token storage.

class CustomStore
def fetch(request)
Return the token from a custom location
end

def store(request, csrf_token)
Store the token in a custom location
end

def reset(request)
Delete the stored session token
end
end


Turn on request forgery protection . Bear in mind that GET and HEAD requests are not checked . You can disable forgery protection on controller by skipping the verification before_action . Valid Options . : only / : except - Only apply forgery protection to a subset of actions . For example only : [ : create : create_all ] . : if / : unless - Turn off the forgery protection entirely depending on the passed Proc or method reference . : prepend - By default the verification of the authentication token will be added at the position of the protect_from_forgery call in your application . This means any callbacks added before are run first . This is useful when you want your forgery protection to depend on other callbacks like authentication methods ( Oauth vs Cookie auth ) . If you need to add verification to the beginning of the callback chain use prepend : true . : with - Set the method to handle unverified request . Built - in unverified request handling methods are : : exception - Raises ActionController :: InvalidAuthenticityToken exception . : reset_session - Resets the session . : null_session - Provides an empty session during request but doesn ' t reset it completely . Used as default if : with option is not specified . You can also implement custom strategy classes for unverified request handling . def handle_unverified_request Custom behavior for unverfied request end end class ApplicationController < ActionController : x : Base protect_from_forgery with : CustomStrategy end : store - Set the strategy to store and retrieve CSRF tokens . Built - in session token strategies are : : session - Store the CSRF token in the session . Used as default if : store option is not specified . : cookie - Store the CSRF token in an encrypted cookie . You can also implement custom strategy classes for CSRF token storage . class CustomStore def fetch ( request ) Return the token from a custom location end def store ( request csrf_token ) Store the token in a custom location end def reset ( request ) Delete the stored session token end end
def protect_from_forgery(options = {})
        options = options.reverse_merge(prepend: false)
        self.forgery_protection_strategy = protection_method_class(options[:with] || :null_session)
        self.request_forgery_protection_token ||= :authenticity_token
        self.csrf_token_storage_strategy = storage_strategy(options[:store] || SessionStore.new)
        before_action :verify_authenticity_token, options
        append_after_action :verify_same_origin_request
      end
def protect_from_forgery ( options = { } ) options = options . reverse_merge ( prepend : false ) self . forgery_protection_strategy = protection_method_class ( options [ :with ] || :null_session ) self . request_forgery_protection_token ||= :authenticity_token self . csrf_token_storage_strategy = storage_strategy ( options [ :store ] || SessionStore . new ) before_action :verify_authenticity_token , options append_after_action :verify_same_origin_request end
Turn on request forgery protection.
Turn on request forgery protection .
options
<not_specific>