Software Development Life Cycle (SDLC)

Study Notes

SDLC emerged as a response to the initial lack of structure in software development
It's a structured approach to developing software, defining distinct phases.

Planning: Planning the entire project; outlining the scope, goals, and resources.
Analysis: Understanding the project's requirements to map the software.
Design: Designing a software solution to meet the defined requirements; includes detailed specifications and architecture.
Implementation: Building the software based on the design specifications.
Testing & Integration: Installing the software in the target environment, performing various tests to identify and resolve bugs, and ensuring successful integration.
Maintenance: Adapting the software to changing requirements and environments; includes ongoing updates, bug fixes, and performance enhancements.

Waterfall Model: A sequential model where each phase must be completed before the next one begins.
Iterative Model: A cyclical model where development occurs in iterations (cycles). Each iteration focuses on adding functionalities and addressing changes based on test results.
Agile Models: Models that emphasize flexibility and responding to change quickly; multiple phases can happen simultaneously. Changes to requirements are not seen as a problem, but an opportunity.

Testing is integrated throughout the project's lifecycle: During requirements, design, implementation, testing, delivery, and maintenance.
Types of testing: unit tests, integration tests, acceptance tests, and regression tests.

The system's core is built; additional parts are constructed and integrated one at a time.
Testing occurs concurrently with new component integration.

Working software kept in a repository.
Developers continuously check-in code, test, and push updates to the repository.
This ensures consistent integration of changes and quick resolution and detection of bugs.

Tests are written before the code they're designed to test.
Aligns developers and testing teams early in the development process and reduces unexpected issues down the line.
Helpful in ensuring that the functionalities and classes are designed according to the intended purpose early on.

A structured approach to the software testing process, guiding the activities.
STLC phases: requirement analysis, test planning, test case development, environment setup, test execution, test closure.

Requirements Analysis: Identifying testable aspects of requirements. Output includes a requirements traceability matrix and an automation feasibility report.
Test Planning: Creates the test plan document based on requirements and test matrices. Output includes an approved plan.
Test Case Development: Constructing the test cases, test data, and automation scripts. Output includes approved test cases, and scripts.
Test Environment Setup: Establishing the testing environment to ensure accurate simulation of target environment. Output is a functional testing environment.
Test Execution: Deploying tests in the testing environment and performing them. Output is the performance of tests and generated reports.
**Test Cycle Closure:**Summarizing test execution results and producing a closure report. Output includes a test closure report.