Implement full autoprune policy support for the quay-distribution Go rewrite, matching the functionality in the Python Quay codebase

Scope

• Namespace-level and repository-level autoprune policies
• NUMBER_OF_TAGS policy method (keep N most recent tags)
• CREATION_DATE policy method (remove tags older than X)
• Tag pattern regex matching
• Background goroutine worker (30s interval)
• Prometheus metrics for
  monitoring

Out of Scope

• Garbage collection / blob cleanup (separate task)
• API endpoints for policy management (uses existing Quay DB)

Technical Details

• New package: internal/autoprune/
• Follow existing
  worker pattern from pkg/auth/jwk/manager.go
• Reads existing Quay tables: namespaceautoprunepolicy, repositoryautoprunepolicy
• Expires tags by setting lifetime_end_ms

Configuration

FEATURE_AUTOPRUNE: true
AUTOPRUNE_WORKER_INTERVAL: "30s"
AUTOPRUNE_BATCH_SIZE: 100
LABELED_EXPIRATION_MINIMUM: "1h"
LABELED_EXPIRATION_MAXIMUM: "104w"

Acceptance Criteria

• [ ] Manager starts/stops cleanly with server lifecycle
• [] Processes namespaces in batches (configurable size)
• [ ] Applies NUMBER_OF_TAGS policies correctly
• [ ] Applies CREATION_DATE policies correctly
• [ ] Respects tag pattern filters
• [ ] Skips immutable tags
• [ ]Prometheus metrics exposed

• [ ] Unit tests for policy engine
• [ ] Integration tests with database
• [ ] Documentation updated

Implementation Phases

Phase 1: Foundation

1. Create internal/autoprune/ directory
2. Implement models.go - policy types, tag metadata
3. Implement config.go - config types with defaults
4. Add config fields to pkg/config/quay_config.go

Phase 2: Core Worker

1. Implement autoprune.go - Manager with Start/Stop
2. Implement worker.go - background loop
3. Implement metrics.go - Prometheus metrics

Phase 3: Policy Engine

1. Implement queries.go - database queries
2. Implement policy_engine.go - policy evaluation
3. Add tag pattern regex matching

Phase 4: Integration

1. Add to pkg/server/server.go - initialize manager
2. Wire shutdown in cmd/quay-distribution/main.go

Phase 5: Testing

1. Unit tests for policy engine
2. Unit tests for worker lifecycle
3. Integration tests with database

🤖 This task description was generated with Claude Code