PhoenixKit V42 Migration: Universal Scheduled Jobs System

This migration introduces a centralized scheduled jobs system that can handle any type of scheduled task (posts, emails, notifications, etc.) using a polymorphic design with behaviour-based handlers.

Changes

Scheduled Jobs Table (phoenix_kit_scheduled_jobs)

• Universal job scheduling with polymorphic resource references
• Handler module storage for dynamic dispatch
• Status tracking (pending, executed, failed, cancelled)
• Retry support with attempt tracking
• Priority-based execution ordering
• Flexible metadata via JSONB args field

Design

The system uses a behaviour pattern where handler modules implement:

• job_type/0 - Returns the job type string
• resource_type/0 - Returns the resource type string
• execute/2 - Executes the job with resource_id and args

PostgreSQL Support

• Uses binary_id primary key
• Optimized indexes for status + scheduled_at queries
• Supports prefix for schema isolation