1 files changed, 38 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/secure_token.rb b/activerecord/lib/active_record/secure_token.rb
new file mode 100644
index 0000000000..0990f815a7
--- /dev/null
+++ b/activerecord/lib/active_record/secure_token.rb
@@ -0,0 +1,38 @@
+module ActiveRecord
+  module SecureToken
+    extend ActiveSupport::Concern
+
+    module ClassMethods
+      # Example using has_secure_token
+      #
+      #   # Schema: User(token:string, auth_token:string)
+      #   class User < ActiveRecord::Base
+      #     has_secure_token
+      #     has_secure_token :auth_token
+      #   end
+      #
+      #   user = User.new
+      #   user.save
+      #   user.token # => "4kUgL2pdQMSCQtjE"
+      #   user.auth_token # => "77TMHrHJFvFDwodq8w7Ev2m7"
+      #   user.regenerate_token # => true
+      #   user.regenerate_auth_token # => true
+      #
+      # SecureRandom::base58 is used to generate the 24-character unique token, so collisions are highly unlikely.
+      #
+      # Note that it's still possible to generate a race condition in the database in the same way that
+      # validates_presence_of can. You're encouraged to add a unique index in the database to deal with
+      # this even more unlikely scenario.
+      def has_secure_token(attribute = :token)
+        # Load securerandom only when has_secure_token is used.
+        require 'active_support/core_ext/securerandom'
+        define_method("regenerate_#{attribute}") { update! attribute => self.class.generate_unique_secure_token }
+        before_create { self.send("#{attribute}=", self.class.generate_unique_secure_token) unless self.send("#{attribute}?")}
+      end
+
+      def generate_unique_secure_token
+        SecureRandom.base58(24)
+      end
+    end
+  end
+end