Consumer supervision tree.

Supervises the Scanner, Manager, and Worker Pool for processing jobs, following the QuiCK paper's consumer architecture.

Architecture

Consumer (Supervisor)
├── Task.Supervisor (worker pool)
│   └── Task* (job execution tasks)
├── Manager (GenServer)
└── Scanner (GenServer)

• Scanner: Continuously scans the pointer index for queues with visible items, also periodically garbage collects stale pointers
• Manager: Receives queue notifications, dequeues items, obtains leases, dispatches to workers
• Task.Supervisor: Dynamic pool of task workers up to concurrency limit
• Worker: Module providing job execution logic with timeout protection

Configuration

• :repo - Required. The Bedrock Repo module
• :workers - Required. Map of topic strings to job modules
• :name - Process name (default: Bedrock.JobQueue.Consumer)
• :root - Required. Root keyspace (from Directory)
• :concurrency - Number of concurrent workers (default: System.schedulers_online())
• :batch_size - Items to dequeue per batch (default: 10)
• :scan_interval - How often to scan for ready queues in ms (default: 100)
• :backoff_fn - Retry backoff function (default: Bedrock.JobQueue.Config.default_backoff/1)
• :gc_interval - How often to garbage collect stale pointers in ms (default: 60_000)
• :gc_grace_period - Grace period before GC considers pointer stale in ms (default: 60_000)

Usage

{:ok, _pid} = Bedrock.JobQueue.Consumer.start_link(
  repo: MyApp.Repo,
  workers: %{"email:send" => MyApp.Jobs.SendEmail},
  concurrency: 10
)