API Testing & Automation

Postman, REST Assured in Java, JWT authentication, and JSON Schema

Backend services power modern software. Learn to test REST APIs with Postman for exploratory checks, and automate with Java REST Assured for CI pipelines. Master HTTP status codes, headers, Bearer tokens, JSON Schema validation, and security testing against BOLA/IDOR vulnerabilities.

11 Chapters128 LessonsTarget Practice: Interactive Practice API Docs

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What You Will Master in This Path

✓Understand HTTP anatomy: methods (GET, POST, PUT, PATCH, DELETE), headers, and payloads
✓Build automated Postman collections with Pre-request scripts and Chai assertions
✓Write production-grade REST Assured automation using the BDD Given-When-Then DSL
✓Enforce API contract integrity using JSON Schema Draft-07 validation

Industry & Career Demand:

API testing is the fastest-growing QA skill, with nearly 85% of automation postings seeking API proficiency.

Compensation Outlook:

₹10 LPA to ₹30+ LPA for dual UI + API automation engineers.

Complete Curriculum Breakdown

What is an API?

Understand what APIs are, why they matter for testing, and build a rock-solid foundation before you touch Postman or write a single test

Postman Basics

Master Postman from installation to sharing collections — send requests, read responses, organize your work, and handle authentication like a pro

Writing Postman Tests

Master Postman test scripts — from basic assertions to chained requests, pre-request scripts, and the Collection Runner. Write tests that catch bugs before they reach production.

Environment Variables and Data-Driven Tests

Stop hardcoding URLs and tokens. Learn Postman variables, environment switching, pre-request scripts, request chaining, and data-driven testing with CSV/JSON files.

Newman CLI

Take your Postman collections out of the GUI and into the terminal. Install Newman, run collections from the command line, generate HTML/JUnit reports, feed CSV/JSON data, wire it into CI/CD pipelines, and use Newman as a Node.js library.

REST Assured with Java

Move beyond Postman. Write API tests in Java using REST Assured — the industry standard library for automated API testing. Master the given/when/then syntax, send GET/POST/PUT/DELETE requests, validate responses with Hamcrest matchers, extract data with JsonPath, and build reusable test specs.

Authentication and Authorization Testing

Master API security testing — authentication vs authorization, API keys, Basic Auth, JWT tokens, OAuth 2.0 flows, token management in test frameworks, testing 401/403 scenarios, role-based access, IDOR vulnerabilities, OWASP API Top 10, and Postman auth handling with auto-refresh.

Schema Validation

Master JSON Schema validation for APIs — understand the blueprint analogy, learn JSON Schema syntax (type, properties, required, constraints), validate responses in Postman (tv4/Ajv) and REST Assured, write schemas for real APIs with nested objects and arrays, auto-generate schemas, integrate schema checks in CI/CD, debug failures, and practice with real exercises.

API Test Automation Framework

Build a production-grade API test automation framework from scratch — understand why scripts fail at scale, design a 6-layer architecture (Config, Base, POJOs, Endpoints, Tests, Reports), set up Maven project structure, implement ConfigReader for multi-environment support, create BaseTest with RequestSpec, model request/response with Jackson POJOs, wrap REST Assured calls in Endpoint classes, write data-driven TestNG tests, integrate Allure reporting, run via testng.xml and Maven profiles, and practice building the whole thing end to end.

Practice: Test a Public API

The capstone project — build a complete API test suite from scratch using JSONPlaceholder and ReqRes.in, covering Postman collections, Newman CLI, REST Assured CRUD tests, schema validation, negative testing, data-driven tests, Allure reporting, and a professional test plan checklist

Hands-On: Practice with a Real API

Send real requests to a live REST API — register, authenticate, browse products, place orders, and handle errors using curl or Postman.

Frequently Asked Questions

Why should I learn REST Assured when I already know Postman?

Postman is excellent for exploratory testing and manual checks. REST Assured integrates directly into Java test frameworks, sharing POJO data models, assertions, and CI reporting with your Selenium suite.