The Complete Guide to API Testing | REST | SOAP | Postman | SoapUI | Automation | Security | Performance | CI/CD | AI Testing
Welcome to the API Testing Handbook, a comprehensive learning repository designed for beginners, manual testers, automation engineers, QA professionals, software developers, DevOps engineers, and anyone looking to master API Testing from scratch to advanced level.
Unlike traditional notes or tutorials, this repository follows a structured learning path with detailed explanations, diagrams, examples, interview preparation, real-world projects, best practices, and automation frameworks.
By the end of this handbook, you'll be able to:
- Understand APIs and Web Services from first principles
- Design effective API test strategies
- Perform REST and SOAP API testing
- Validate JSON and XML responses
- Work with Postman and SoapUI
- Automate API testing using Rest Assured
- Create scalable API automation frameworks
- Perform Database Validation
- Implement Security Testing
- Execute Performance Testing
- Integrate API tests into CI/CD pipelines
- Debug APIs efficiently
- Design enterprise-level API testing solutions
- Prepare confidently for QA and SDET interviews
API-Testing-Handbook
│
├── README.md
│
├── 01-Introduction-to-APIs
├── 02-Web-Services
├── 03-HTTP-Protocol
├── 04-REST-Architecture
├── 05-SOAP-Web-Services
├── 06-API-Documentation
├── 07-Request-Response
├── 08-HTTP-Methods
├── 09-Status-Codes
├── 10-Headers-Cookies-Sessions
├── 11-Authentication
├── 12-Authorization
├── 13-JSON
├── 14-XML
├── 15-JSONPath
├── 16-XPath
├── 17-Postman
├── 18-SoapUI
├── 19-Groovy
├── 20-Assertions
├── 21-Test-Design
├── 22-Test-Cases
├── 23-Test-Execution
├── 24-API-Validation
├── 25-Negative-Testing
├── 26-Error-Handling
├── 27-Database-Testing
├── 28-SQL
├── 29-Mock-Services
├── 30-Security-Testing
├── 31-Performance-Testing
├── 32-API-Automation
├── 33-Rest-Assured
├── 34-Java
├── 35-TestNG
├── 36-Maven
├── 37-Framework-Design
├── 38-Reporting
├── 39-Jenkins
├── 40-Git
├── 41-GitHub
├── 42-Docker
├── 43-Kubernetes
├── 44-CI-CD
├── 45-Microservices
├── 46-GraphQL
├── 47-gRPC
├── 48-WebSockets
├── 49-Versioning
├── 50-Best-Practices
├── 51-Debugging
├── 52-Interview-Questions
├── 53-Real-World-Projects
├── 54-Cheat-Sheets
├── 55-AI-in-API-Testing
├── Resources
└── Assets
Introduction to APIs
- What is an API?
- API Evolution
- API Lifecycle
- API Categories
- Public APIs
- Private APIs
- Internal APIs
- Partner APIs
- API Gateway
- API Ecosystem
Web Services
- Web Services
- SOAP
- REST
- WSDL
- XML
- JSON
- Service Architecture
- RPC
- Document Style
- Message Exchange
HTTP Fundamentals
- HTTP
- HTTPS
- URI
- URL
- Endpoints
- DNS
- Client Server Model
- Request Lifecycle
- Response Lifecycle
- HTTP Versions
REST APIs
- REST Principles
- REST Constraints
- Resources
- Statelessness
- Caching
- URI Design
- Versioning
- Pagination
- Filtering
- Sorting
SOAP APIs
- SOAP Envelope
- SOAP Header
- SOAP Body
- SOAP Fault
- Namespaces
- WSDL
- XSD
- XML Schema
Request Components
- URL
- Headers
- Authorization
- Cookies
- Query Parameters
- Path Parameters
- Body
- Form Data
- Multipart
- Binary Data
Response Components
- Status Codes
- Response Body
- Headers
- Cookies
- Schema Validation
- Business Validation
- Error Messages
Authentication
- Basic Auth
- Bearer Token
- JWT
- OAuth2
- API Key
- Mutual TLS
- Session Authentication
Postman
- Installation
- Collections
- Variables
- Environments
- Scripts
- Assertions
- Monitors
- Newman
- Mock Servers
SoapUI
- Projects
- Test Suites
- Test Cases
- Assertions
- Property Transfer
- Groovy Scripts
- Data Sources
- Mock Services
- Security Testing
Automation
- Java
- Rest Assured
- Maven
- TestNG
- Framework Design
- Parallel Execution
- Logging
- Reporting
Database Testing
- SQL
- CRUD
- Transactions
- Data Validation
- Joins
- Stored Procedures
Security Testing
- OWASP API Top 10
- Authentication
- Authorization
- Injection
- Broken Object Level Authorization
- Rate Limiting
- CORS
Performance Testing
- JMeter
- Load Testing
- Stress Testing
- Spike Testing
- Volume Testing
- Endurance Testing
CI/CD
- Jenkins
- GitHub Actions
- Azure DevOps
- Docker
- Kubernetes
Interview Preparation
- REST Interview Questions
- SOAP Interview Questions
- SQL Questions
- Automation Questions
- Framework Questions
- Scenario-Based Questions
Real Projects
- User Management API
- E-Commerce API
- Banking API
- Payment Gateway
- Healthcare API
- Food Delivery API
- Social Media API
AI in API Testing
- AI Test Generation
- Prompt Engineering
- MCP
- AI Bug Analysis
- AI Automation
- Self-Healing Tests
- AI Code Review
- Beginners
- Students
- QA Engineers
- Manual Testers
- Automation Testers
- SDETs
- Backend Developers
- Full Stack Developers
- DevOps Engineers
- Performance Testers
- Security Testers
- Beginner to Advanced Learning Path
- Step-by-Step Tutorials
- Theory with Practical Examples
- Architecture Diagrams
- HTTP Flow Diagrams
- REST and SOAP Examples
- Postman Collections
- SoapUI Projects
- Rest Assured Framework
- Java Source Code
- Groovy Examples
- SQL Scripts
- Real-World Projects
- Mini Assignments
- Practice Exercises
- Common Interview Questions
- Best Practices
- Cheat Sheets
- Production-Level Framework Design
| Category | Technologies |
|---|---|
| API Types | REST, SOAP, GraphQL, gRPC |
| API Clients | Postman, SoapUI |
| Languages | Java, Groovy, SQL |
| Automation | Rest Assured, TestNG |
| Build Tools | Maven |
| CI/CD | Jenkins, GitHub Actions |
| Containers | Docker |
| Orchestration | Kubernetes |
| Security | OAuth2, JWT, API Keys |
| Performance | JMeter |
| Version Control | Git, GitHub |
Contributions are welcome. Feel free to open issues, submit pull requests, improve documentation, or add real-world examples.
This repository is released under the MIT License.
Vishal Aggarwal
QA Engineer | API Tester | Automation Tester | AI in Testing | Continuous Learner
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