Testing audit paths

An audit test should prove the boundary most likely to fail, not merely that a commit returns.

Small tests

Use cache-backed repositories for fast commit, snapshot, change, and shadow tests. Verify author and commit properties, snapshot order, and reconstruction. Codec tests should include corrupted data because several decoders return null rather than throwing. If your code uses ShadowProvider, include a JaVers compatibility smoke test because it reflects into typeMapper.

Persistence tests

For Exposed, test schema creation separately from migration-managed startup. Commit more than one version, reconstruct the repository, and verify head restoration and newest-first history. Exercise a duplicate GlobalId/version and a failure between snapshot and sequence updates. The release tests cover H2 plus database smoke paths in ExposedCdoSnapshotRepositoryH2Test.kt.

For Redis, run Lettuce and Redisson suites independently against Testcontainers. Verify repository reconstruction, history, shadow loading, connection failure, and your chosen persistence/eviction settings. For Kafka, assert the produced key and payload, the 30-second failure boundary, and the fact that reads stay empty.

End-to-end projection test

OrderProjectionFlowTest starts Kafka and Redis through bluetape4k Testcontainers, uses H2 for domain and audit tables, publishes OrderPlaced and OrderMarkedPaid, polls Kafka, and verifies Redis status. It proves the happy-path ordering under those fixtures. It does not prove crash recovery, duplicate delivery handling, offset correctness, or production database behavior.

Run the module test that owns the boundary; keep Redis and Kafka container suites sequential when shared launchers or ports can interact. The Projects manual covers the underlying Testcontainers launchers.