Building Distributed Applications in Gin: A hands-on guide for Go developers to build and deploy distributed web apps with the Gin framework

482 Pages·2021·27.156 MB·English

by  Mohamed Labouardy

Building Distributed
Applications in Gin
A hands-on guide for Go developers to build and
deploy distributed web apps with the Gin framework
Mohamed Labouardy
BIRMINGHAM—MUMBAI
Building Distributed Applications in Gin
Copyright © 2021 Packt Publishing
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Published: June 2021
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Published by Packt Publishing Ltd.
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ISBN 978-1-80107-485-8
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I want to thank my wife, Mounia. You've always supported me, always
patiently listened while I struggled to get this done, and always made me
believe I could finish this. I love you.
Thanks as well to all the folks at Packt who worked with me on the
production and promotion of the book. It was truly a team effort.
Contributors
About the author
Mohamed Labouardy is the CTO and cofounder of Crew.work, and a DevSecOps
evangelist. He is the founder of Komiser.io, a regular conference speaker, and the author of
several books about serverless and distributed applications.
You can find him on Twitter (@mlabouardy).
This book is dedicated to my parents, even though they will never know
unless someone tells them about this.
About the reviewer
Dmitry Goryunov was born in 1987 in Tomsk, a really nice city in Siberia that many
talented engineers call their home. His first coding experience was writing macros for
Ultima Online at the age of 12.
Ever since 2007, throughout his entire career, he has enjoyed building distributed software
systems. Currently, he lives in Berlin and works for Zalando SE, where he is solving
MLOps challenges for natural language processing systems.

Table of Contents
Preface
Section 1: Inside the Gin Framework
1
Getting Started with Gin
Technical requirements 4 Installing and configuring Gin 19
What is Gin? 4 Dependency management in
Setting up the Go environment 9 Golang 24
Writing a custom HTTP handler 32
Linux/FreeBSD 10
Windows 11 Summary 35
MacOS 13 Questions 35
Integrated development environment 15
Further reading 35
Installing Go tools 18
Section 2: Distributed Microservices
2
Setting Up API Endpoints
Technical requirements 40 PUT /recipes/{id} 56
Exploring API functionality 40 DELETE /recipes/{id} 60
GET /recipes/search 63
Defining the data model 43
HTTP endpoints 46 Writing the OpenAPI
Specification 65
Implementing HTTP routes 46
Installing Go Swagger 66
POST /recipes 46
Swagger metadata 67
GET /recipes 51
viii Table of Contents
Summary 75 Further reading 76
Questions 75
3
Managing Data Persistence with MongoDB
Technical requirements 78 The UpdateOne operation 98
Running a MongoDB Server 78
Designing the project's layout 101
Installing Docker CE 80
Caching an API with Redis 106
Running a MongoDB container 83
Running Redis in Docker 107
Configuring Go's MongoDB driver 88 Optimizing MongoDB queries 110
Exploring MongoDB queries 90 Performance benchmark 122
The InsertMany operation 90 Summary 125
The Find operation 94
Questions 126
The InsertOne operation 95
Further reading 126
4
Building API Authentication
Technical requirements 128 cookies 149
Exploring authentication 128 Authenticating with Auth0 156
Using API keys 129 Building an HTTPS server 161
Self-signed certificates 163
Introducing JWTs 133
Sign-in HTTP handler 137 Summary 171
Renewing a JWT 143 Questions 171
Hashing and salting passwords 147
Further reading 171
Persisting client sessions and
5
Serving Static HTML in Gin
Technical requirements 174 Creating the view templates 187
Serving static files 174 Creating reusable templates 194
Rendering HTML templates 179
Table of Contents ix
Building a self-contained web Exploring React components 207
application 196 Resolving cross-origin requests 212
Bundling static files 202
Summary 223
Building a SPA 204 Questions 223
Getting started with React 205 Further reading 223
6
Scaling a Gin Application
Technical requirements 226 Using Docker multi-stage builds 248
Scaling workloads with a Scaling services with Docker Compose 250
message broker 226
Using the NGINX reverse proxy 254
Deploying RabbitMQ with Docker 234
Caching assets with HTTP cache
Exploring the Producer/Consumer
headers 269
pattern 237
Setting HTTP caching headers 270
Scaling horizontally with Docker
Summary 271
replicas 247
Further reading 271
Section 3: Beyond the Basics
7
Testing Gin HTTP Routes
Technical requirements 276 Scripting in Postman 297
Testing Gin HTTP handlers 276 Running collections with Newman 304
Generating code coverage Summary 305
reports 282
Questions 306
Performing integration tests with
Further reading 306
Docker 286
Discovering security
vulnerabilities 289
Gosec 289
Securing Go modules with Snyk 291
Running Postman collections 295