Microservices: Up and Running: A Step-by-Step Guide to Building a Microservices Architecture

319 Pages·2020·10.064 MB·English

by  Ronnie Mitra, Irakli Nadareishvili

Microservices
Up & Running
A Step-by-Step Guide to Building a
Microservices Architecture
Ronnie Mitra &
Irakli Nadareishvili

Microservices: Up and Running
A Step-by-Step Guide to Building
a Microservices Architecture
Ronnie Mitra and Irakli Nadareishvili
BBeeiijjiinngg BBoossttoonn FFaarrnnhhaamm SSeebbaassttooppooll TTookkyyoo
Microservices: Up and Running
by Ronnie Mitra and Irakli Nadareishvili
Copyright © 2021 Mitra Pandey Consulting, Ltd. and Irakli Nadareishvili. All rights reserved.
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978-1-492-07545-5
[LSI]
To every person who took the time to chronicle and share their experiences. And to
Kairav, who didn’t help me write this dedication.
—Ronnie Mitra
To Lucas, who was born shortly after we started working on this book and whose smiles
gave me the strength to complete this book in the middle of a global pandemic; to my
wife Ana, for her support; and to my amazing students at Temple University, in Phila‐
delphia, who kindly “test drove” early versions of a lot of the content in this book.
—Irakli

Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
1. Toward a Microservices Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
What Are Microservices? 2
Reducing Coordination Costs 4
The Coordination Cost Problem 4
The Hard Parts 6
Learning by Doing 7
The “Up and Running” Microservices Model 8
Decisions, Decisions… 10
Writing a Lightweight Architectural Decision Record 11
Summary 13
2. Designing a Microservices Operating Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Why Teams and People Matter 16
Team Size 17
Team Skills 18
Interteam Coordination 19
Introducing Team Topologies 21
Team Types 21
Interaction Modes 23
Designing a Microservices Team Topology 24
Establish a System Design Team 24
Building a Microservices Team Template 26
Platform Teams 29
Enabling and Complicated-Subsystem Teams 31
Consumer Teams 32
v
Summary 34
3. Designing Microservices: The SEED(S) Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Introducing the Seven Essential Evolutions of Design for Services: The
SEED(S) Method 36
Identifying Actors 37
Example Actors in Our Sample Project 39
Identifying Jobs That Actors Have to Do 39
Using Job Story Format to Capture JTBDs 41
Example JTBDs in Our Sample Project 42
Discovering Interaction Patterns with Sequence Diagrams 43
Deriving Actions and Queries from JTBDs 45
Example Queries and Actions for Our Sample Project 47
Describing Each Query and Action as a Specification with an Open Standard 48
Example OAS for an Action in Our Sample Project 49
Getting Feedback on the API Specification 53
Implementing Microservices 53
Microservices Versus APIs 54
Summary 56
4. Rightsizing Your Microservices: Finding Service Boundaries. . . . . . . . . . . . . . . . . . . . . . . 57
Why Boundaries Matter, When They Matter, and How to Find Them 57
Domain-Driven Design and Microservice Boundaries 59
Context Mapping 62
Synchronous Versus Asynchronous Integrations 65
A DDD Aggregate 66
Introduction to Event Storming 66
The Event-Storming Process 68
Introducing the Universal Sizing Formula 73
The Universal Sizing Formula 74
Summary 74
5. Dealing with the Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Independent Deployability and Data Sharing 75
Microservices Embed Their Data 77
Embedding Data Should Not Lead to an Explosion in the Number of
Database Clusters 78
Data Embedding and the Data Delegate Pattern 79
Using Data Duplication to Solve for Independence 81
Distributed Transactions and Surviving Failures 82
Event Sourcing and CQRS 85
vi | Table of Contents
Event Sourcing 85
Improving Performance with Rolling Snapshots 91
Event Store 92
Command Query Responsibility Segregation 93
Event Sourcing and CQRS Beyond Microservices 94
Summary 95
6. Building an Infrastructure Pipeline. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
DevOps Principles and Practices 98
Immutable Infrastructure 99
Infrastructure as Code 100
Continuous Integration and Continuous Delivery 102
Setting Up the IaC Environment 104
Set Up GitHub 104
Install Terraform 105
Configuring Amazon Web Services 106
Setting Up an AWS Operations Account 106
Configure the AWS CLI 110
Setting Up AWS Permissions 112
Creating an S3 Backend for Terraform 115
Building an IaC Pipeline 116
Creating the Sandbox Repository 117
Understanding Terraform 119
Writing the Code for the Sandbox Environment 120
Building the Pipeline 123
Testing the Pipeline 133
Summary 135
7. Building a Microservices Infrastructure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Infrastructure Components 137
The Network 138
The Kubernetes Service 139
The GitOps Deployment Server 140
Implementing the Infrastructure 142
Installing kubectl 142
Setting Up the Module Repositories 142
The Network Module 145
The Kubernetes Module 160
Setting Up Argo CD 171
Testing the Environment 175
Cleaning Up the Infrastructure 177
Table of Contents | vii
Summary 178
8. Developer Workspace. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Coding Standards and the Developer’s Setup 180
10 Workspace Guidelines for a Superior Developer Experience 181
Setting Up a Containerized Environment Locally 187
Installing Multipass 188
Entering the Container and Mapping Folders 189
Installing Docker 190
Testing Docker 191
Advanced Local Docker Usage: Installing Cassandra 192
Installing Kubernetes 193
Summary 195
9. Developing Microservices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Designing Microservice Endpoints 197
Flights Microservice 201
Reservations Microservice 201
Designing an OpenAPI Specification 202
Implementing the Data for a Microservice 208
Redis for the Reservations Data Model 209
MySQL Data Model for the Flights Microservice 211
Implementing Code for a Microservice 212
The Code Behind the Flights Microservice 213
Health Checks 218
Introducing a Second Microservice to the Project 220
Hooking Services Up with an Umbrella Project 226
Summary 229
10. Releasing Microservices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Setting Up the Staging Environment 232
The Ingress Module 233
The Database Module 234
Forking the Staging Infrastructure Project 234
Configuring the Staging Workflow 235
Editing the Staging Infrastructure Code 237
Shipping the Flight Information Container 241
Introducing Docker Hub 241
Configuring Docker Hub 242
Configuring the Pipeline 242
Deploying the Flights Service Container 246
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