Finished phase005

app/models/access_key.rb

@@ -0,0 +1,65 @@
+class AccessKey < ApplicationRecord
+  DEFAULT_ROTATION_FREQUENCY_DAYS = 30
+  KEY_LENGTH = 32
+
+  validates :raw_key, presence: true
+  validates :generated_at, presence: true
+  validates :auto_rotation_frequency_days,
+            numericality: { only_integer: true, greater_than: 0 }
+
+  def self.current
+    order(generated_at: :desc, id: :desc).first || create_current!
+  end
+
+  def self.create_current!
+    create!(
+      raw_key: generate_raw_key,
+      generated_at: Time.current,
+      auto_rotate: true,
+      auto_rotation_frequency_days: DEFAULT_ROTATION_FREQUENCY_DAYS
+    )
+  end
+
+  def self.rotate!
+    previous_key = current
+
+    transaction do
+      UserSession.delete_all
+      create!(
+        raw_key: generate_raw_key,
+        generated_at: Time.current,
+        auto_rotate: previous_key.auto_rotate,
+        auto_rotation_frequency_days: previous_key.auto_rotation_frequency_days
+      )
+    end
+  end
+
+  def self.rotate_if_needed!
+    key = current
+    return key unless key.auto_rotate? && key.expired?
+
+    rotate!
+  end
+
+  def self.generate_raw_key
+    SecureRandom.urlsafe_base64(KEY_LENGTH)
+  end
+
+  def matches?(submitted_key)
+    ActiveSupport::SecurityUtils.secure_compare(raw_key, submitted_key.to_s)
+  rescue ArgumentError
+    false
+  end
+
+  def expired?
+    generated_at <= auto_rotation_frequency_days.days.ago
+  end
+
+  def disable_auto_rotation!
+    update!(auto_rotate: false)
+  end
+
+  def enable_auto_rotation!
+    update!(auto_rotate: true)
+  end
+end