Interactive Testing Methodologies Lesson

🎯 Purpose

Unit testing involves testing individual components or modules of software in isolation to ensure they work correctly. It's the foundation of good testing practices and helps catch bugs early in development.

🔄 Process

The process follows a simple pattern: Input → Function → Output, while monitoring for side effects like I/O operations, file changes, or database interactions.

• Write test cases for individual functions/methods
• Mock external dependencies
• Assert expected outputs for given inputs
• Verify no unwanted side effects occur

✨ Benefits

• Early bug detection
• Easier debugging and maintenance
• Documentation of expected behavior
• Confidence in code changes

🎯 Purpose

Integration testing focuses on testing the interfaces and interaction between integrated components to detect interface defects.

🔄 Process

Tests how different modules work together when combined. The diagram shows component A integrating with B1 and B2, each having their own sub-components.

• Big Bang: Test all components together
• Top-down: Test from top-level down
• Bottom-up: Test from bottom components up
• Sandwich/Hybrid: Combination approach

✨ Key Focus Areas

• Data flow between modules
• Interface compatibility
• API contracts and responses
• Database integration

🎯 Purpose

System testing evaluates the complete integrated system to verify that it meets specified requirements in a production-like environment.

🔄 Process

Tests the entire system as a black box, with all modules (1-4) working together as shown in the diagram.

• Functional testing of complete workflows
• Non-functional testing (performance, security)
• End-to-end user scenarios
• Environment and configuration testing

✨ Types of System Testing

• Functional testing
• Performance testing
• Security testing
• Usability testing
• Compatibility testing

🎯 Purpose

Load testing determines how a system performs under expected and peak load conditions, measuring response time, throughput, and error rates.

🔄 Process

Multiple users simultaneously access the application while monitoring performance metrics like response time, throughput, and error rates.

• Define performance requirements
• Create realistic user scenarios
• Gradually increase load
• Monitor system resources and response times

✨ Types of Load Testing

• Load Testing: Normal expected load
• Stress Testing: Beyond normal capacity
• Spike Testing: Sudden load increases
• Volume Testing: Large amounts of data

🎯 Purpose

Error testing (also called fault injection or chaos testing) deliberately introduces failures to test system resilience and error handling capabilities.

🔄 Process

Different types of "assaults" are performed on services to test their resilience:

• Latency Assault: Introduce delays in responses
• Exception Assault: Force exceptions in code paths
• KillApp Assault: Terminate application processes
• Memory/CPU exhaustion

✨ Benefits

• Improved system reliability
• Better error handling
• Increased confidence in production
• Disaster recovery validation

🎯 Purpose

Test automation creates an automated pipeline that runs tests continuously throughout the development lifecycle, from commit to deployment.

🔄 Process

The automation pipeline follows these stages:

• Commit Change: Developer commits code
• Trigger Build: Automatic build initiation
• Build: Compile and package application
• Run Test: Execute automated test suites
• Notify Test Outcome: Report results to team

✨ Benefits

• Faster feedback cycles
• Consistent test execution
• Reduced manual effort
• Early bug detection
• Continuous quality assurance