Postman API Fundamentals Student Expert

This repository contains my Postman API Fundamentals Student Expert Certification project completed as a Web Engineering Lab task at my university.

Student: Redwan Rahman
Department of Computer Science and Engineering
Daffodil International University
Course Name: Web Engineering Lab
Course Code: CSE416

Lab Instructor:
Mr. Md. Alvee Ehsan
Lecturer, Department of Computer Science and Engineering
Daffodil International University
https://faculty.daffodilvarsity.edu.bd/profile/cse/alveehsan.html

Fork Link for Evaluation:
Postman API Fundamentals Student Expert Test Collection

📋 Table of Contents

• Project Overview
• API Endpoints Implemented
• File Structure
• Key Learning Outcomes
• Technical Implementation
• Automation & Scripting
• How to Use

🎯 Project Overview

This project demonstrates mastery of API testing and automation using Postman. The implementation includes comprehensive testing of a library management system API with full CRUD operations, authentication, and advanced scripting features.

Core Features Implemented:

• ✅ Complete CRUD operations for book management
• ✅ Query parameter filtering and search functionality
• ✅ Dynamic variable management and data persistence
• ✅ API authentication with API keys
• ✅ Automated testing with pre/post-request scripts
• ✅ Collection organization and documentation

🔗 API Endpoints Implemented

1. Get All Books

• Method: GET
• URL: {{baseUrl}}/books
• Description: Retrieve all books from the library collection
• Query Parameters: None

2. Get Fiction Books (Filtered)

• Method: GET
• URL: {{baseUrl}}/books
• Description: Retrieve fiction books that are not checked out
• Query Parameters:
  • genre=fiction
  • checkedOut=false

3. Get Book by ID

• Method: GET
• URL: {{baseUrl}}/books/:id
• Description: Retrieve a specific book using its unique identifier
• Path Variables: :id (replaced with actual book ID)

4. Add New Book

• Method: POST
• URL: {{baseUrl}}/books
• Description: Add a new book to the library collection
• Body (JSON):

{
  "title": "Sahih al-Bukhari",
  "author": "Imam Muhammad ibn Ismail al-Bukhari",
  "genre": "hadith-collection",
  "yearPublished": 846
}

• Post-Request Script: Saves book ID to collection variable

5. Checkout Book

• Method: PATCH
• URL: {{baseUrl}}/books/:id
• Description: Update book status to checked out
• Body (JSON):

{
  "checkedOut": true
}

6. Delete Book

• Method: DELETE
• URL: {{baseUrl}}/books/:id
• Description: Remove a book from the library collection
• Path Variables: :id (uses saved collection variable)

7. Skill Check Endpoint

• Method: POST
• URL: {{skillcheckBaseUrl}}/post
• Description: Certification validation endpoint
• Query Parameters: movieName=Kingdom of Heaven
• Authorization: API Key (student-expert: skillcheck)
• Body (JSON):

{
  "actorName": "Orlando Bloom"
}

• Post-Response Script: Saves actorName as favoriteActor variable

📁 File Structure

postman-api-fundamentals-student-expert/
├── Request JSON/                    # API request specifications
│   ├── get-all-books.json          # Get all books request
│   ├── get-fiction-books.json      # Get filtered fiction books
│   ├── get-book-by-id.json         # Get book by ID request
│   ├── add-book.json               # Add new book request
│   ├── checkout-book.json          # Checkout book request
│   ├── delete-book.json            # Delete book request
│   └── skillcheck.json             # Skill check request
├── Scripts/                        # Postman automation scripts
│   ├── save id.js                  # Script to save book ID
│   ├── skillcheck.js               # Skill check automation
│   ├── postman test script.js      # General testing script
│   ├── final check.js              # Final validation script
│   └── halfway check.js            # Intermediate validation
├── Response Examples/              # API response samples
│   ├── add book response.json      # Sample add book response
│   ├── Sahih Bukhari.json          # Book data example
│   └── checkout.json               # Checkout response example
└── README.md                       # Project documentation

🎓 Key Learning Outcomes

API Fundamentals

• Understanding of RESTful API principles and HTTP methods
• Mastery of request-response lifecycle and status codes
• Proper handling of JSON payloads and data structures
• Knowledge of API endpoints, paths, and parameter usage

Postman Proficiency

• Advanced collection and request organization
• Efficient use of environment and collection variables
• Query parameter manipulation and path variable usage
• Response interpretation and data extraction techniques

Authentication & Security

• Implementation of API key authentication
• Understanding of request-level authorization
• Secure handling of credentials and sensitive data

Automation & Scripting

• Pre-request script implementation for dynamic data
• Post-response script automation for data persistence
• JavaScript-based testing and validation logic
• Variable management and data flow between requests

Testing & Validation

• Comprehensive API endpoint testing strategies
• Status code validation and error handling
• Response data verification and extraction
• Automated test suite development

⚙️ Technical Implementation

Variable Management

The project implements sophisticated variable management:

• Collection Variables: id, favoriteActor
• Environment Variables: baseUrl, skillcheckBaseUrl
• Dynamic Data Flow: Automatic ID capture and reuse across requests

Authentication Strategy

• API Key Authentication: Implemented at request level
• Key-Value Pairs: student-expert: skillcheck
• Secure Credential Management: No hardcoded sensitive data

Data Persistence

• Automatic extraction and storage of response data
• Cross-request data sharing through collection variables
• Persistent state management across test sessions

🔄 Automation & Scripting

Post-Request Scripts

Save Book ID Script (save id.js):

// Save the "id" value from the response to a variable named "id"
const id = pm.response.json().id;
// Save the id as a collection variable named "id"
pm.collectionVariables.set("id", id);

Skill Check Script (skillcheck.js):

// Parse the JSON response
const jsonData = pm.response.json();

// Check if actorName exists in the response
if (jsonData.json && jsonData.json.actorName) {
  // Save it as a collection variable named "favoriteActor"
  pm.collectionVariables.set("favoriteActor", jsonData.json.actorName);
  console.log("favoriteActor variable set to:", jsonData.json.actorName);
} else {
  console.warn("actorName not found in response");
}

🚀 How to Use

1. Import Collection: Import the Postman collection using the fork link provided
2. Set Environment: Configure baseUrl and skillcheckBaseUrl variables
3. Run Requests: Execute requests in sequence for proper data flow
4. Monitor Variables: Check collection variables for automatically saved data
5. Validate Responses: Review response data and status codes
6. Execute Scripts: Post-request scripts will automatically manage variables

🏆 Certification Achievement

This project successfully demonstrates all required competencies for the Postman API Fundamentals Student Expert certification, including:

• ✅ API request creation and execution
• ✅ Response handling and data extraction
• ✅ Variable management and automation
• ✅ Authentication implementation
• ✅ Script-based testing and validation
• ✅ Collection organization and documentation