Integration Testing

Tests interactions between separate components without the need for end-to-end tests.

Test Basis:

• Software and System Design
• Architecture
• Workflows
• Use Cases
  • Sequence diagrams

Test objects:

• Sub-systems and databases
• Infrastructure
• Interfaces
  • APIs

Two types of integration testing:

• Component
  Verifies smaller units that have unit tests work together correctly (e.g., correct interface, data flow).

• System
  Tests interaction between systems such as databases, internal and external APIs, and infrastructure. Often requires mocking (e.g., external payment gateway) and often does work that end-to-end testing cannot or should not.