Keboola Component Tester

Testing approach

Three levels, in priority order:

1. Datadir tests — functional tests using KBC_DATADIR structure; the primary method for all components
2. Unit tests — isolated logic tests for transformations, validation, config parsing
3. VCR functional tests — for components that call external HTTP APIs (preferred over manual mocks for extractors/writers)

Choosing VCR vs mocks

Use VCR (keboola.datadirtest) when the component makes external HTTP calls:

• Records real API interactions once → replays deterministically in CI without credentials
• More realistic than hand-rolled mocks; catches API contract changes
• Required for extractors; recommended for writers that call external APIs