Postman Cookbook (Oliver James) (Z-Library)

POSTMAN COOKBOOK Hand-picked Solutions and Techniques across API Design, Testing, Performance, Networking, Kubernetes and Integration O liver 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 Response and Debugging Recipe 2: Applying Authentication in GraphQL Situation Practical Solution Obtaining OAuth 2.0 Access Token Configuring GraphQL Request in Postman Executing Secured GraphQL Query Handling Authentication Errors Automating Token Refresh Recipe 3: Testing and Debugging GraphQL APIs Situation Practical Solution Creating Test Suite in Postman Writing Tests for GraphQL Queries Writing Tests for GraphQL Mutations Debugging with Postman’s Console Iterating and Refining Tests Automating Test Execution Recipe 4: Working with Protobuf and gRPC Services Situation Practical Solution Understanding Protobuf Indirect Interaction with gRPC Services Setting up gRPC Gateway Sample Program: Fetching User Profile using Postman Sample Program: Updating User's Email using Postman

Recipe 5: Observing gRPC Calls Situation Practical Solution Setting up gRPC Proxy Define HTTP Mapping in Protobuf Implement and Run gRPC Gateway Observing gRPC Calls with Postman via gRPC Proxy Debugging and Iteration Summary Chapter 6. Continuous Integration and Deployment (CI/CD) Introduction Recipe 1: Integrating Postman with CI/CD Tools Situation Practical Solution Configuring CI/CD Pipeline Handling Test Results Enhancing Feedback Mechanisms Recipe 2: Automation Strategies with Newman Situation Practical Solution Dynamic Test Selection Environment Variable Injection Conditional Workflows in CI/CD Integrating Test Reports Continuous Feedback Loop Recipe 3: Setting up Jenkins for API Testing Situation Practical Solution Export Postman Collection and Environment Configure Jenkins Pipeline Define Pipeline Script Execute and Monitor Pipeline Recipe 4: GitHub Actions for API Workflows

Situation Practical Solution Configuring the Workflow Execute and Monitor the Workflow Recipe 5: Docker Integration for Isolated Testing Situation Practical Solution Preparing Dockerfile Building Docker Image Running Docker Container Reviewing Test Results Recipe 6: Monitoring Deployment Pipelines with Prometheus Situation Practical Solution Installing Prometheus Configuring Prometheus to Monitor Jenkins Starting Prometheus with Configuration Viewing Metrics and Setting up Alerts Summary Chapter 7: API Scalability and Performance Introduction Recipe 1: Using Postman to scale API Situation Practical Solution Enhancing Test Collection for Scalability Executing Collection with Variable Load Monitoring and Analysis Identifying Bottlenecks Addressing Scalability Concerns Continuous Testing and Monitoring Recipe 2: Managing Load Balancing and High Traffic Situation Practical Solution

Choose a Load Balancer Implement Health Checks Scaling and Auto-scaling Test Load Balancing Setup Recipe 3: Implementing API Caching Techniques Situation Practical Solution Identify Cachable Data Choose Caching Strategy Implementing Redis for Application-level Caching Utilizing HTTP Caching Monitor and Adjust Recipe 4: Troubleshooting Common Scalability Issues Situation Practical Solution Database Bottlenecks Inefficient Code Paths Infrastructure Limitations Memory Leaks Networking Issues Recipe 5: Optimizing API Response Times Situation Practical Solution Efficient Data Fetching and Processing Use HTTP/2 for Improved Performance Implement Caching where Applicable Minimize Third-party API Calls Optimize Database Queries Recipe 6: High Availability and Disaster Recovery Plans Situation Practical Solution High Availability Setup Disaster Recovery Plan Summary

Chapter 8: Integrating with Third-Party Services Introduction Recipe 1: Basics of Third-Party API Integration Situation Practical Solution Understanding API Documentation Making First API Call Handling Authentication Testing and Validation Recipe 2: Securely Managing API Keys and Tokens Situation Practical Solution Environment Variables for Credential Storage Secrets Management Services Access Control and Minimal Privilege Regular Rotation of Keys and Tokens Monitoring and Auditing Recipe 3: Automating Third-Party Notifications Situation Practical Solution Choosing Notification Service Integrating Slack Notifications with Jenkins Plugin Configuration Setting up AWS CloudWatch Alerts to Slack Recipe 4: Data Synchronization Techniques Situation Practical Solution Identify Data Entities for Synchronization Choose Synchronization Strategy Implementing Direct API Integration for AWS S3 Synchronizing Data with External CRMs using Webhooks Handling Rate Limits and Ensuring Reliability Recipe 5: Handling Rate Limits and Quotas Situation

Practical Solution Understanding Rate Limits and Logging Rate Limit Handling Strategy Caching Responses Distributing Requests Utilizing Webhooks where Available Recipe 6: Error Management in Integrations Situation Practical Solution Categorizing Errors Implementing Retry Logic for Transient Errors Graceful Error Handling in Application Logic Error Reporting and Alerts Recipe 7: Advanced Authentication Flows Situation Practical Solution OAuth for Third-Party Service Integration Securely Managing API Keys for Jenkins Integration Implementing mTLS for Secure Communication Summary Chapter 9: Working with Kubernetes and Microservices Introduction Recipe 1: Deploying APIs on Kubernetes Situation Practical Solution Containerizing API Creating Kubernetes Deployment Exposing API with Service Verifying Deployment Recipe 2: Performing Service Discovery Situation Practical Solution Kubernetes DNS for Service Discovery

Defining Kubernetes Service Discovering Services using DNS Using Environment Variables for Service Discovery Recipe 3: Logging Kubernetes Service Situation Practical Solution Understanding Kubernetes Logging Architecture Fluentd for Log Collection Configuring Application Logging Recipe 4: Connecting API Gateways Situation Practical Solution Deploying Kong in Kubernetes Configuring Kong as API Gateway Enabling TLS/SSL Implementing Rate Limiting and Authentication Recipe 5: Securing Microservices Situation Practical Solution Implement Network Policies Configuring Istio for mTLS Authorization with Istio Using Kubernetes Secrets for Sensitive Data Recipe 6: Scaling Microservices with Kubernetes Situation Practical Solution Horizontal Pod Autoscaling (HPA) Custom Metrics for Advanced Scaling Summary Chapter 10: API Networking and Protocols Introduction Recipe 1: Understanding HTTP and HTTPS in Postman Understanding HTTP and HTTPS in Postman