Processing Composite Store

• ID: storage.composite.processing-store
• Summary: Composite role that combines lease and state-writer responsibilities for processor loops.

Interface Methods

Acceptance methods (AddAsync, AddBatchAsync) remain on append interfaces and are not part of processing composites.

SQL Behavior

• Composite methods execute against the same physical table as append and operations roles.
• Lease path reads due rows and marks owner plus expiry.
• State path updates status and timestamps with lease guard checks.

Concurrency Model

• Composite usage keeps lease and state transitions in one store implementation, which avoids cross-store race windows.
• PostgreSQL adapters use FOR UPDATE SKIP LOCKED for disjoint claims.
• Persist operations return applied and skipped counts for lost-lease detection.

Index Interaction

• Lease scan index is required for claim operations.
• Idempotency and topic indexes are not directly used by processing methods but remain part of the same table definition.

Observability

• Composite operations drive processor metrics:
  • ...processor.leases_acquired
  • ...processor.succeeded or ...processor.published
  • ...processor.failed
  • ...processor.dead_lettered
  • ...processor.persist_skipped
  • ...processor.persist_rejected
• Queue-depth gauges reflect status movement across pending, processing/publishing, and terminal states.

Test Coverage

LiteBus.Storage.IntegrationTests (PostgreSql/)

• PostgreSqlInboxEndToEndTests and PostgreSqlOutboxEndToEndTests: lease plus persist path.
• PostgreSqlInboxProcessorLeaseStressTests: concurrent processor claims and single terminal outcome.
• PostgreSqlModuleRegistrationTests: role interfaces resolve to one singleton store instance.

LiteBus.Storage.UnitTests

• Module dependency tests validate that storage cannot build without its parent durable module.
• EF and InMemory module tests in same project verify one-instance role mapping per axis adapter.

Related Docs

• Architecture
• storage.role.lease
• storage.role.state-writer