Postman Cookbook: Hand-picked Solutions and Techniques across API Design, Testing, Performance, Networking, Kubernetes and Integration

Postman Cookbook

Hand-picked Solutions and Techniques across API Design, Testing, Performance, Networking, Kubernetes and Integration

Oliver James

Preface

For developers, programmers, and DevOps engineers venturing into the hard world of API development, the Postman Cookbook becomes a must-read. This short solutions book offers recipes and troubleshooting approaches to address typical API lifecycle management challenges. Using Postman's rich features, readers of all skill levels will learn how to create APIs that will improve workflows, increase productivity, and lead to operational success.

The book covers a wide range of subjects, from the fundamentals of web-based communication to more complex topics including protocol stacks, secure communication protocols, and the dynamics of WebSocket interactions. The following sections cover advanced subjects such as custom protocol handling, network troubleshooting, and proxy management, allowing readers to confidently solve complex networking challenges.

This book covers more than simply the technical aspects of Kubernetes. It discusses the influence of security measures, maximizing performance, and successful scaling solutions. These features are critical for microservice architectures and cloud-native apps. This resource teaches early developers and programmers the foundations of API testing and development, including networking and protocols.

Upon completion of this book, readers will have a thorough understanding of API development with Postman. They will be able to confidently handle the problems of modern computing.

In this book you will learn to:

Enable real-time API connectivity for dynamic apps using WebSocket capability.

Protect API endpoints from security flaws by configuring SSL/TLS in Postman.

Define, implement, and debug bespoke protocols to connect proprietary systems to Postman.

Master the art of network optimisation and troubleshooting using Postman to ensure your API runs smoothly.

Use Postman's proxy management to safely access APIs in a variety of network settings.

Test APIs in Kubernetes and improve the deployment and development of microservices.

Exploit Postman's features for thorough API tracking, logging, and analysis of performance.

Secure API access with Postman's advanced authentication flows—OAuth, JWT, and more.

Streamline your workflows and elevate your API development using Postman's environment and variable management.

Become proficient in HTTP and HTTPS protocols to establish safe and efficient data transfers and API calls.

Prologue

Being the author of the Postman Cookbook, my goal is to simplify the intricate realm of API development and share with you a collection of tactics, pointers, and methods that have played a significant role in my development experience. In this book, I aim to impart all the wisdom I've gained, with a particular emphasis on how to make Postman, a vital component of the API ecosystem, approachable and motivating for programmers of all stripes.

Actually, I was more driven by sheer necessity than genuine interest when I initially came across Postman. There was a clear need for a tool that could do more than simply submit queries as the difficulties of API development increased. What began as a hesitant exploration has now evolved into a profound admiration for Postman's capabilities. Postman was like a Swiss Army knife for API development; it helped me design API calls, write tests, and automate operations.

Troubles did arise along the way. There were a lot of obstacles that seemed insurmountable, such as understanding HTTP and HTTPS, protecting connections using SSL and TLS, and fixing network problems. But there was a chance to learn and develop from every difficulty. In order to help you overcome obstacles and reach milestones in your API development journey, this book condenses those learnings into practical recipes.

Covering everything from the basics of secure communication and the HTTP/HTTPS protocols to more complex subjects like WebSocket interactions and custom protocol handling, the Postman Cookbook is designed to walk you through every aspect of API development. It's written from the heartfelt belief that grasping these ideas is critical to maximising Postman's potential.

There is a strong focus on security, which is essential when developing APIs. In this book, you will find out how to set up SSL/TLS in Postman for secure endpoints and how to build sophisticated authentication procedures to safeguard your APIs. The book also digs into network troubleshooting and optimisation, giving you the tools to diagnose and improve API performance.

As a developer working with APIs, one of the most satisfying things is seeing your work implemented in a cloud-native or microservices architecture. You will get the necessary skills to confidently deploy, manage, and scale APIs after reading the chapters on Kubernetes, logging, and monitoring.

All of the recipes in this book are meant to be a starting point that you can add to your existing body of knowledge and expertise. There are practical solutions that you can put into practice right now, whether you're dealing with network problems, managing proxies, or growing microservices.

Putting this book together has been an adventure in self-discovery, education, and communication. It is my sincere wish that the Postman Cookbook becomes an integral part of your API development journey, rather than only a reference. My sincere wish is that this book provides you with the answers you're looking for and motivates you to keep pushing the boundaries of what's possible in the ever-changing world of API development.

I hope that by sharing these ideas, you will be better able to understand and handle the challenges of API development and will be motivated to explore Postman's capabilities to their fullest potential.

Copyright © 2024 by GitforGits

All rights reserved. This book is protected under copyright laws and no part of it may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without the prior written permission of the publisher. Any unauthorized reproduction, distribution, or transmission of this work may result in civil and criminal penalties and will be dealt with in the respective jurisdiction at anywhere in India, in accordance with the applicable copyright laws.

Published by: GitforGits

Publisher: Sonal Dhandre

www.gitforgits.com

support@gitforgits.com

Printed in India

First Printing: February 2024

Cover Design by: Kitten Publishing

For permission to use material from this book, please contact GitforGits at support@gitforgits.com.

Content

Preface

Acknowledgement

Chapter 1: Up and Running with Postman

Introduction

Recipe 1: Installing and Setting Up Postman

Situation

Practical Solution

Download Postman for Linux

Extract the Postman Archive

Launching Postman

Initial Configuration

Verify the Setup

Recipe 2: Understanding the Postman Interface

Situation

Practical Solution

Workspace Overview

Building and Sending Requests

Collections and Environments

History and APIs

Using Console and Visualizer

Search and Settings

Recipe 3: Making Your First API Request

Situation

Practical Solution

Create a New Request

Setup the Request

Send the Request

Recipe 4: Managing Collections and Environments

Situation

Practical Solution

Recipe 5: Sharing and Importing Collections

Situation

Practical Solution

Recipe 6: Utilizing Global Variables and Initial Values

Situation

Practical Solution

Open the Manage Environments Window

Add Global Variables

Using Global Variables in Requests

Recipe 7: Basic Debugging with Postman Console

Situation

Practical Solution

Open Postman Console

Send API Request

Review Console Output

Adjust and Retry

Summary

Chapter 2: Designing Simple to Complex APIs

Introduction

Recipe 1: Creating and Documenting RESTful APIs

Situation

Practical Solution

Define API Endpoints

Create Requests in Postman

Document the API

Recipe 2: Mock Servers and Simulating API Responses

Situation

Practical Solution

Create Mock Server in Postman

Define Mock Responses

Utilize the Mock Server

Recipe 3: Version Control for APIs

Situation

Practical Solution

Utilize Postman's Version Tagging

Export and Store Collections in Version Control Systems

Integrate Changes and Collaborate

Leverage for Documentation

Recipe 4: Prototyping Backend APIs

Situation

Practical Solution

Setting up Mock Server Responses

Simulating Real-World Scenarios with Scripting

Iterating Based on Feedback

Documenting Prototyping Decisions

Recipe 5: Effective Use of Postman for API Design

Situation

Practical Solution

Organizing API Endpoints into Collections

Employing Environments for Flexible Configuration

Leverage Mock Servers for Rapid Prototyping

Integrate Tests for Design Validation

Recipe 6: Feedback Loops with Mock Servers

Situation

Practical Solution

Creating Mock Server

Setting up Mock Responses for User Creation and Verification

Sharing Mock Server for Feedback

Collecting and Implementing Feedback

Summary

Chapter 3: Advanced API Requests and Workflows

Introduction

Recipe 1: Advanced Request Chaining Techniques

Situation

Practical Solution

Creating New User Request

Extracting User ID

Fetching User Details with User ID

Chaining Requests

Recipe 2: Scripting Pre-request and Test Scripts

Situation

Practical Solution

Dynamically Set Request Data

Validating the Response with Test Scripts

Recipe 3: Dynamic Variables in API Testing

Situation

Practical Solution

Incorporating Dynamic Variables in Request Data

Testing with Dynamic Variables

Leveraging Dynamic Data for Comprehensive Testing

Recipe 4: Building Complex Workflows

Situation

Practical Solution

Define Workflow

Chain Requests using Variables

Configure Subsequent Requests

Automate the Workflow Execution

Verify and Iterate

Recipe 5: Performing Data-Driven Testing

Situation

Practical Solution

Prepare Data File

Setup Your Request for Data-Driven Testing

Utilize Collection Runner for Data-Driven Testing

Analyze Results

Recipe 6: Managing Workflows with Collection Runner

Situation

Practical Solution

Prepare Collection

Configuring Collection Runner

Running Tests

Analyzing Results

Recipe 7: Error Handling and Debugging Scripts

Situation

Practical Solution

Implementing Error Handling in Test Scripts

Using Postman Console for Debugging

Iterative Debugging with Postman’s Visualizer

Summary

Chapter 4. Testing and Securing APIs

Introduction

Recipe 1: Writing Effective API Tests

Situation

Practical Solution

Define Clear Test Objectives

Create Test Cases in Postman

Incorporate Negative Testing

Utilize Dynamic Data and Variables

Automate and Integrate Tests

Recipe 2: Performing Data-Driven Test

Situation

Practical Solution

Prepare Data File

Configure Request in Postman

Use Collection Runner for Data-Driven Testing

Recipe 3: Implementing OAuth 2.0 and API Keys

Situation

Practical Solution

Obtain OAuth 2.0 Credentials

Configuring OAuth 2.0 in Postman

Using the Token

Obtaining an API Key

Configuring API Key in Postman

Recipe 4: Setting up Automated REST API Test

Situation

Practical Solution

Organize Tests in Postman

Export Postman Collection

Install Newman

Run Collection Using Newman

Analyze Test Results

Recipe 5: Securing API Call Sequences

Situation

Practical Solution

Implement Strong Authentication and Authorization Mechanisms

Use HTTPS for API Calls

Validate and Sanitize Input Data

Implement Rate Limiting and Monitoring

Use Postman Tests for Security Assertions

Sequence Automation with Collection Runner

Recipe 6: Validate REST API Parameters

Situation

Practical Solution

Defining Parameter Validation Rules

Implementing Validation in API

Testing Parameter Validation with Postman

Automating Validation Tests

Continuous Integration for Ongoing Validation

Recipe 7: Continuous Integration (CI) Testing with Newman

Situation

Practical Solution

Export Postman Collection and Environment

Install Newman in CI Environment

Configure Newman to Run Collection

Handle Test Results

Integrate Newman into CI Services

Summary

Chapter 5. Managing GraphQL and gRPC with Postman

Introduction

Recipe 1: Executing GraphQL Queries and Mutations

Situation

Practical Solution

Setting up Postman Environment for GraphQL

Executing GraphQL Query

Executing GraphQL Mutation

Analyzing