Salesforce APIs (REST, SOAP, Bulk, Streaming, Pub/Sub) need testing like any other API.
Tools: Postman, Insomnia, Newman (CLI), curl, custom scripts.
Test scenarios:
- Authentication (OAuth flows).
- CRUD operations on standard / custom objects.
- Bulk API job submissions.
- SOQL queries.
- Custom REST endpoints.
- Error handling (invalid input, rate limits).
Patterns:
- Postman collections per API.
- Newman for CI/CD execution.
- Schema validation.
- Performance under load.
Salesforce-specific:
- API versioning.
- Connected App / OAuth setup.
- Daily API call limits.
- Bulk API job lifecycle.
Senior insight: API tests are part of integration testing. Critical for integration-heavy orgs.