Microservices: Flexible Software Architecture

432 Pages·2016·16.33 MB·English

by  Eberhard Wolff

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Microservices
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Microservices
Flexible Software Architecture
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Eberhard Wolff
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To my family and friends for their support.
And to the computing community for all the fun it
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Contents at a Glance
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
Part I: Motivation and Basics . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 1: Preliminaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Chapter 2: Microservice Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Part II: Microservices: What, Why, and Why Not? . . . . . . . . 25
Chapter 3: What Are Microservices? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Chapter 4: Reasons for Using Microservices . . . . . . . . . . . . . . . . . . . . . . . 55
Chapter 5: Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
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Chapter 6: Microservices and SOA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Part III: Implementing Microservices . . . . . . . . . . . . . . . . . . 95
Chapter 7: Architecture of Microservice-Based Systems . . . . . . . . . . . . . . . 99
Chapter 8: Integration and Communication . . . . . . . . . . . . . . . . . . . . . . 163
Chapter 9: Architecture of Individual Microservices . . . . . . . . . . . . . . . . 193
Chapter 10: Testing Microservices and Microservice-Based Systems . . . . 213
Chapter 11: Operations and Continuous Delivery of Microservices . . . . . 237
Chapter 12: Organizational Effects of a Microservices-Based
Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Part IV: Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Chapter 13: Example of a Microservices-Based Architecture . . . . . . . . . . 303
Chapter 14: Technologies for Nanoservices . . . . . . . . . . . . . . . . . . . . . . . 343
Chapter 15: Getting Started with Microservices . . . . . . . . . . . . . . . . . . . . 369
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 375
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Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxv
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxxi
About the Author . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxxiii
Part I: Motivation and Basics . . . . . . . . . . . . . . . . . . . . . . . . . 1
Chapter 1: Preliminaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Overview of Microservice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Microservice: Preliminary Definition . . . . . . . . . . . . . . . . . . . . . 3
Deployment Monoliths . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2 Why Microservices? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Strong Modularization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
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Easy Replaceability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Sustainable Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Further Development of Legacy Applications . . . . . . . . . . . . . . 6
Time-to-Market . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Independent Scaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Free Choice of Technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Continuous Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Chapter 2: Microservice Scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.1 Modernizing an E-Commerce Legacy Application . . . . . . . . . . . . 11
Scenario . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Reasons to Use Microservices . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Slow Continuous Delivery Pipeline . . . . . . . . . . . . . . . . . . . . . . 12
Parallel Work Is Complicated . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Bottleneck During Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
ix