Spring Boot in Practice

584 Pages·2022·37.965 MB·English

by  Somnath Musib

P
IN RACTICE

Somnath Musib
Foreword by Josh Long
M A N N I N G
Spring Boot
in Practice
SOMNATH MUSIB
Foreword by JOSH LONG
MANNING
SHELTER ISLAND
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To my parents—for sacrificing everything to raise us
and
To my son, Abhirup—for adding new meaning and purpose to my life
brief contents
PART 1 ................................................................................... 1
1 ■ Booting Spring Boot 3
PART 2 ................................................................................. 29
2 ■ Common Spring Boot tasks 31
3 ■ Database access with Spring Data 70
4 ■ Spring Boot: Autoconfiguration and Actuator 131
5 ■ Securing Spring Boot applications 184
6 ■ Implementing additional security with Spring Security 233
7 ■ Developing RESTful Web services with Spring Boot 297
PART 3 ............................................................................... 347
8 ■ Reactive Spring Boot application development 349
PART 4 ............................................................................... 397
9 ■ Deploying Spring Boot applications 399
PART 5 ............................................................................... 439
10 ■ Spring Boot with Kotlin, Native Image, and GraphQL 441
iivv
contents
foreword xiii
preface xv
acknowledgments xvii
about this book xix
about the author xxii
about the cover illustration xxiii
PART 1 ........................................................................ 1
1 Booting Spring Boot 3
1.1 Introducing Spring Boot 4
Why Spring Boot? 4 ■ What is Spring Boot? 5 ■ Spring Boot
core features 6 ■ Spring Boot components 7
1.2 Code examples 9
Maven vs. Gradle 9 ■ Java vs. Kotlin 9 ■ Database support 9
Lombok 9
1.3 Getting started with Spring Boot 10
Your first Spring Boot project 10 ■ Spring Boot project
structure 10 ■ Creating an executable JAR file 20 ■ Exploring
the JAR file 20 ■ Shutting down a Spring Boot application 21
v
vi CONTENTS
1.4 Spring Boot additional concepts 22
Spring Boot startup events 22 ■ Listening events in a Spring Boot
application 23 ■ Custom Spring Boot starters 25 ■ Custom
autoconfiguration 26 ■ Failure analyzers 26 ■ Spring Boot
actuator 26 ■ Spring Boot developer tool 27
PART 2 ...................................................................... 29
2 Common Spring Boot tasks 31
2.1 Managing configurations 32
Using the SpringApplication class 32 ■ Using @PropertySource 33
Config data file 35 ■ OS environment variable 38
2.2 Creating custom properties with
@ConfigurationProperties 40
Technique: Defining custom properties with @ConfigurationProperties
in a Spring Boot application 41
2.3 Executing code on Spring Boot application startup 46
Technique: Using CommandLineRunner to execute code at Spring
Boot application startup 46
2.4 Customizing logging in a Spring Boot application 51
Technique: Understanding and customizing default Spring Boot
logging in a Spring Boot application 52 ■ Technique: Using
Log4j2 to configure logging in a Spring Boot application 56
2.5 Validate user data using Bean Validation 60
Technique: Using built-in Bean Validation annotations to validate
business entity in a Spring Boot application 60 ■ Technique:
Defining and using custom Bean Validation annotation to validate
a POJO in a Spring Boot application 63
3 Database access with Spring Data 70
3.1 Introducing Spring Data 71
Why Spring Data? 72 ■ Spring Data modules 72
3.2 Configuring a database in a Spring Boot application 74
Technique: Configuring a relational database in a Spring Boot
application 74 ■ Technique: Configuring MongoDB database in
a Spring Boot application 79 ■ Technique: Initializing a
relational database schema with a Spring Boot application 82
CONTENTS vii
3.3 Understanding the CrudRepository interface 86
Technique: Managing domain objects in a relational database with
Spring Data JPA 88 ■ Technique: Creating a custom Spring Data
repository with Spring Data JPA to manage domain objects in a
relational database 94
3.4 Retrieve data from a database using Spring Data 97
Defining query methods 97 ■ Technique: Defining custom query
methods to retrieve domain objects from a relational database with
Spring Data JPA 98 ■ Implementing pagination with
PagingAndSortingRepository 101 ■ Technique: Using
PagingAndSortingRepository interface to paginate and sort the
data 101 ■ Specifying query using @NamedQuery 104
Technique: Using a named query to manage domain objects in a
relational database with Spring Data JPA 105
3.5 Specifying query using @Query 107
Technique: Using @Query annotation to define queries and retrieve
domain objects in a relational database with Spring Data JPA 107
3.6 Using Criteria API with Spring Data JPA 111
Technique: Using Criteria API to manage domain objects in a
relational database with Spring Data JPA 111
3.7 Using QueryDSL with Spring Data JPA 114
Technique: Using QueryDSL to manage domain objects in a
relational database with Spring Data JPA 114
3.8 Managing domain object relationships 119
Technique: Managing domain objects with many-to-many
relationships in a relational database with Spring Data JPA 121
4 Spring Boot: Autoconfiguration and Actuator 131
4.1 Understanding Spring Boot autoconfiguration 132
Understanding @Conditional annotation 134 ■ Deep dive into
autoconfiguration 136
4.2 Using Spring Boot DevTools 139
Property defaults 139 ■ Automatic restart 140 ■ Live
reload 140
4.3 Creating a custom failure analyzer 140
Technique: Creating a custom Spring Boot FailureAnalyzer 141
4.4 Spring Boot Actuator 144
Technique: Configuring Spring Boot Actuator in a Spring Boot
application 145 ■ Understanding Spring Boot Actuator
viii CONTENTS
endpoints 146 ■ Managing Spring Boot Actuator
endpoints 149 ■ Health endpoint deep dive 150
Creating a custom Spring Boot HealthIndicator 154
Technique: Defining a custom Spring Boot actuator
HealthIndicator 155
4.5 Info endpoint deep dive 158
Technique: Configuring info Spring Boot Actuator endpoint 158
Technique: Configuring a custom info contributor to provide custom
application info in the Spring Boot Actuator endpoint 162
4.6 Creating a custom Spring Boot Actuator endpoint 164
Technique: Creating a custom Spring Boot actuator endpoint 164
Spring Boot actuator metrics 170 ■ Creating custom metrics 174
Gauge 176 ■ Metrics dashboard with Prometheus and
Grafana 179
5 Securing Spring Boot applications 184
5.1 Introducing Spring Security 185
5.2 Hello Spring Security with Spring Boot 187
Technique: Enabling application security with Spring Security
in a Spring Boot application 187 ■ Filter, FilterChain,
and Spring Security 192 ■ Spring Security architecture 195
Authenticating a user 197 ■ Spring Security
autoconfiguration 200
5.3 Using Spring Security 202
Technique: Customizing the default Spring Security login page of a
Spring Boot application 202 ■ Technique: Configuring in-
memory authentication with custom users in Spring Security in a
Spring Boot application 207 ■ Technique: Configuring JDBC
authentication with Spring Security in a Spring Boot
application 215 ■ Technique: Implementing JDBC authentication
with custom UserDetailsService in a Spring Boot application 219
Technique: Implementing LDAP authentication in a Spring Boot
application 224 ■ Technique: Implementing HTTP basic
authentication in a Spring Boot application 229
6 Implementing additional security with Spring Security 233
6.1 Enabling HTTPS in a Spring Boot application 235
Technique: Enabling HTTPS in a Spring Boot application 235
6.2 Securing secrets in Spring Cloud Vault 238
Technique: Managing application secrets with HashiCorp Vault
in a Spring Boot application 239
CONTENTS ix
6.3 Implementing user registration 242
Technique: Implementing user registration with Spring Security in a
Spring Boot application 242
6.4 Implementing email verification at user registration 251
Technique: Validating user email addresses in a Spring Boot
application 251
6.5 Controlling multiple incorrect login attempts 261
Technique: Controlling multiple incorrect login attempts
in a Spring Boot application 261
6.6 Implementing a Remember Me feature 267
Technique: Enabling a Remember Me feature in a Spring Boot
application with Spring Security 268
6.7 Implementing reCAPTCHA 270
Technique: Enabling Google reCAPTCHA in a Spring Boot
application with Spring Security 271
6.8 Enabling two-factor authentication with Google
Authenticator 276
Technique: Enabling two-factor authentication in a Spring Boot
application 276
6.9 Authentication with OAuth2 287
Technique: Enabling sign in with Google in a Spring Boot
application 288
6.10 Securing Actuator endpoints 292
Technique: Securing Spring Boot Actuator endpoints 294
7 Developing RESTful Web services with Spring Boot 297
7.1 Developing a RESTful API with Spring Boot 298
Technique: Developing a RESTful API using Spring Boot 298
7.2 Managing exceptions in a Spring Boot RESTful API 306
Technique: Handling exceptions in a RESTful API 306
7.3 Testing a RESTful API 311
Technique: Testing a RESTful API in a Spring Boot
application 311
7.4 Documenting a RESTful API 317
Technique: Documenting a RESTful API with OpenAPI 317