Mirror Rules Model

🔍 Overview

The MirrorRule model links a main Link to its immediate mirror/backup link.

• main_link and mirror_link are one-to-one, so each link can have at most one “next” and one “previous”.
• Multiple MirrorRule records form a chain of backups.

The model is responsible for switching traffic in Voluum when an active link is blocked.

---

📑 Fields

Field	Type	Description
main_link	OneToOne Link	Current (working) link.
mirror_link	OneToOne Link	Next backup link.
created_at	datetime	Creation timestamp.
updated_at	datetime	Update timestamp.
switched	bool	Whether the switch was completed successfully.
switched_at	datetime	When the switch was completed.
owner	Foreign Key User	Owner of the link chain (nullable).

---

🧩 Methods

switch(action_by="system")

Attempts to switch traffic from main_link.link to mirror_link.link by updating Voluum.

Behavior

• Raises an error if the rule was already switched (switched=True).
• Calls VoluumController.update_link(old_link, new_link).
• On Voluum failure:
  • sends a Telegram notification
  • marks the mirror link (and its backups) as ignored
• On success:
  • sets switched=True and switched_at=now()
  • promotes the mirror link to active
  • sends a Telegram notification
  • warns if there are no further backups available.