Pro RESTful APIs with Micronaut: Build Java-Based Microservices with REST, JSON, and XML (2023) – Sanjay Patni

Chapter 1: Fundamentals of RESTful APIs ……………………………………………. 1

Abstract ……………………………………………………………………… 1
SOAP vs. REST …………………………………………………………… 4
Web Architectural Style ……………………………………………………. 7
Client-Server …………………………………………………………. 7
Uniform Resource Interface ……………………………………… 8
Layered System ………………………………………………………. 8
Caching …………………………………………………………………. 8
Stateless ……………………………………………………………….. 9
Code on Demand …………………………………………………….. 9
HATEOAS ………………………………………………………………. 10
What Is REST? ………………………………………………………… 11
REST Basics …………………………………………………………….. 12
REST Fundamentals ……………………………………………………… 13
Summary ………………………………………………………………….. 15
Chapter 2: Micronaut ………………………………………………………………….. 17

Abstract ……………………………………………………………………. 17
Comparison of Micronaut with Spring Boot ……………………….. 18
Ease of Installation ……………………………………………………… 18
Natively Cloud Enabled ………………………………………………… 19
Serverless Functions ……………………………………………………. 19
Application Configuration ……………………………………………. 20
Messaging System Support …………………………………………. 21
Security ………………………………………………………………….. 22
Caching ………………………………………………………………….. 23
Management and Monitoring ………………………………………. 23
API Portfolio ………………………………………………………………. 24
Online Flight ……………………………………………………………. 24
Message …………………………………………………………………… 25
Software …………………………………………………………………. 26
Micronaut ……………………………………………………………….. 26
JDK 11 ……………………………………………………………………… 27
POSTMAN ………………………………………………………………. 27
CURL ……………………………………………………………………… 27
IDE …………………………………………………………………………… 27
Maven …………………………………………………………………… 28
Setting Up an IDE ……………………………………………………….. 28
Configuring Visual Studio Code ……………………………………. 29
Summary ………………………………………………………………….. 30
Chapter 3: Introduction: XML and JSON ………………………………………….. 31

Abstract ……………………………………………………………………. 31
What Is XML? ……………………………………………………………. 31
XML Comments ………………………………………………………. 33
Why Is XML Important? ………………………………………………… 34
How Can You Use XML? ………………………………………………… 35
Pros and Cons of XML …………………………………………………….. 35
What Is JSON? …………………………………………………………… 36
JSON Syntax …………………………………………………………….. 36
Why Is JSON Important? ………………………………………………… 38
How Can You Use JSON? ………………………………………………. 40
Pros and Cons of JSON ……………………………………………………. 40
XML and JSON Comparison ……………………………………………. 41
Implementing APIs to Return XML and JSON Messages ………….. 42
Summary ………………………………………………………………….. 49
Chapter 4: API Design and Modeling ………………………………………………… 51

Abstract ……………………………………………………………………. 51
API Design Strategies ……………………………………………………….. 51
API Creation Process and Methodology …………………………… 54
Process …………………………………………………………………… 54
API Methodology ……………………………………………………….. 54
Domain Analysis or API Description ……………………………. 55
Architecture Design ……………………………………………………. 56
Prototyping ……………………………………………………………… 57
Implementation ………………………………………………………. 58
Publish ……………………………………………………………………. 58
API Modeling ……………………………………………………………… 58
Comparison of API Modeling ……………………………………………… 60
In summary ………………………………………………………………… 61
Best Practices …………………………………………………………….. 62
Keep Your Base URL Simple and Intuitive ……………………… 62
Error Handling ………………………………………………………… 64
Error Code ………………………………………………………………. 65
Versioning ………………………………………………………………… 66
Partial Response ……………………………………………………….. 67
Pagination ………………………………………………………………. 67
Multiple Formats ……………………………………………………….. 68
API Façade ………………………………………………………………. 68
API Solution Architecture …………………………………………….. 69
Mobile Solutions ……………………………………………………….. 70
Cloud Solutions ……………………………………………………….. 70
Web Solutions ………………………………………………………. 70
Integration Solutions …………………………………………………… 71
Multichannel Solutions ………………………………………………… 71
Smart TV Solutions ……………………………………………………… 71
Internet of Things ……………………………………………………….. 71
Stakeholders in API Solutions ………………………………………………. 72
API Providers …………………………………………………………… 72
API Consumers ………………………………………………………. 72
End Users ………………………………………………………………. 72
API Modeling …………………………………………………………… 72
Summary ………………………………………………………………….. 80
Chapter 5: API Portfolio and Framework ……………………………………………. 81

Abstract ……………………………………………………………………. 81
API Portfolio Architecture …………………………………………………… 81
Requirements …………………………………………………………… 82
Consistency …………………………………………………………….. 82
Reuse ……………………………………………………………………… 82
Customization ………………………………………………………… 83
Discoverability ……………………………………………………….. 83
Longevity ………………………………………………………………… 83
How Do We Enforce These Requirements—Governance? ………. 83
Consistency …………………………………………………………….. 84
Reuse ……………………………………………………………………… 84
Customization ………………………………………………………… 84
Discoverability ……………………………………………………….. 84
Change Management ………………………………………………… 85
API Framework …………………………………………………………… 85
Process APIs: Services Layer ………………………………………. 86
System APIs: Data Access Object ………………………………… 87
Experience APIs: API Façade ……………………………………….. 87
Services Layer Implementation …………………………………… 87
Summary ………………………………………………………………….. 95
Chapter 6: API Platform and Data Handler ………………………………………….. 97

Abstract ……………………………………………………………………. 97
API Platform Architecture …………………………………………………… 97
Why Do We Need an API Platform? …………………………………. 98
So What Is an API Platform? ………………………………………………. 98
So Which Capabilities Does the API Platform Have? ……………. 99
API Development Platform ………………………………………………… 99
API Runtime Platform ……………………………………………………….. 101
API Engagement Platform ………………………………………………. 101
How Is an API Platform Organized? What Is the Architecture of the API Platform? …………………………………………………………… 102
How Does the API Architecture Fit in the Surrounding Technical Architecture of an Enterprise? ……………………………………… 103
Data Handler ………………………………………………………………… 105
Data Access Object ……………………………………………………… 105
Command Query Responsibility Segregation (CQRS) …….. 106
SQL Development Process ……………………………………………. 106
NoSQL Process ………………………………………………………… 107
Do I Have to Choose Between SQL and NoSQL? …………… 107
Why a Single REST API? ………………………………………………. 107
Summary ………………………………………………………………….. 126
Chapter 7: API Management and CORS …………………………………………….. 127

Abstract ……………………………………………………………………. 127
Façade …………………………………………………………………………. 127
Façade Pattern …………………………………………………………. 127
API Façade ………………………………………………………………. 128
API Management …………………………………………………………. 130
API Life Cycle ……………………………………………………………… 131
API Retirement ……………………………………………………………. 132
API Monetization ……………………………………………………. 133
Cross-Origin Resource Sharing (CORS) ……………………………… 134
Summary ………………………………………………………………….. 134