Java Spring Boot Microservices Example Step By Step Guide

🎓 Top 15 Udemy Courses (80-90% Discount): My Udemy Courses - Ramesh Fadatare — All my Udemy courses are real-time and project oriented courses. ▶️ Subscribe to My YouTube Channel (178K+ subscribers): Java Guides on YouTube ▶️ For AI, ChatGPT, Web, Tech, and Generative AI, subscribe to another channel: Ramesh Fadatare on YouTube In this tutorial, we will learn how to build a simple Microservices project using Spring Boot 3, Spring Cloud, and PostgreSQL database.

In this microservices project, you'll explore essential concepts such as API Gateway, Config Server, Discovery Server, and hands-on implementation of two real-world microservices, Student and School.

Prerequisites Ensure you have the following software installed on your system before proceeding:- Java Development Kit (JDK) 17 or later - Maven - Docker (optional, for containerization) Microservices Architecture Here is the Microservices Architecture for our Microservices project that we are going to build in this tutorial: Let's understand the Microservices project components: API Gateway The API Gateway serves as the single entry point for all client requests, managing and routing them to the appropriate microservices.Config Server The Config Server centralizes configuration management for all microservices, simplifying application maintenance and consistency across environments.Discovery Server The Discovery Server provides service registration and discovery, enabling seamless service-to-service communication within the microservices ecosystem.Student Microservice The Student Microservice is responsible for managing student-related data and operations, such as adding, updating, and retrieving student records.School Microservice The School Microservice manages school-related data and operations, including adding, updating, and retrieving school records.Using OpenFeign - Inter-Service Communication This project demonstrates inter-service communication using OpenFeign, a declarative REST client that simplifies service-to-service communication within the microservices ecosystem.Distributed Tracing - Using Zipkin The project showcases the use of Zipkin for distributed tracing, enhancing application observability and enabling the visualization and troubleshooting of latency issues.1.

Create Student Microservice Let's build student microservice step by step.Create Spring Boot Project Let's create a student microservice as a Spring boot project using the spring initializr.

Refer to the below screenshot to enter details while creating the spring boot application using the spring initializr: Here is the complete pom.xml file for your reference: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>student</artifactId> <version>0.0.1-SNAPSHOT</version> <name>student</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project> Configure PostgreSQL Database Create an application.yml file under /resources folder and add the following content: Don’t forget to change the spring.datasource.username and spring.datasource.password as per your PostgreSQL installation.

Also, create a database named students in PostgreSQL before proceeding to the next section.server: port: 8090 spring: application: name: students datasource: driver-class-name: org.postgresql.Driver url: jdbc:postgresql://localhost:5432/students username: username password: password jpa: hibernate: ddl-auto: create database: postgresql database-platform: org.hibernate.dialect.PostgreSQLDialect JPA Entity - Student Let's create a Student JPA entity and add the following code to it: import jakarta.persistence.Entity; import jakarta.persistence.GeneratedValue; import jakarta.persistence.Id; import lombok.*; @Entity @Getter @Setter @AllArgsConstructor @NoArgsConstructor @Builder public class Student { @Id @GeneratedValue private Integer id; private String firstname; private String lastname; private String email; private Integer schoolId; } Repository Layer - StudentRepository import org.springframework.data.jpa.repository.JpaRepository; import java.util.List; public interface StudentRepository extends JpaRepository<Student, Integer> { List<Student> findAllBySchoolId(Integer schoolId); } Service Layer - StudentService import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Service; import java.util.List; @Service @RequiredArgsConstructor public class StudentService { private final StudentRepository repository; public void saveStudent(Student student) { repository.save(student); } public List<Student> findAllStudents() { return repository.findAll(); } public List<Student> findAllStudentsBySchool(Integer schoolId) { return repository.findAllBySchoolId(schoolId); } } Controller Layer - StudentController import lombok.RequiredArgsConstructor; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.*; import java.util.List; @RestController @RequestMapping("/api/v1/students") @RequiredArgsConstructor public class StudentController { private final StudentService service; @PostMapping @ResponseStatus(HttpStatus.CREATED) public void save( @RequestBody Student student ) { service.saveStudent(student); } @GetMapping public ResponseEntity<List<Student>> findAllStudents() { return ResponseEntity.ok(service.findAllStudents()); } @GetMapping("/school/{school-id}") public ResponseEntity<List<Student>> findAllStudents( @PathVariable("school-id") Integer schoolId ) { return ResponseEntity.ok(service.findAllStudentsBySchool(schoolId)); } } That's completed our student microservice development.

2. Create School Microservice Create Spring Boot Project Let's create a school microservice as a Spring boot project using the spring initializr.

Refer to the below screenshot to enter details while creating the spring boot application using the spring initializr: Here is the complete pom.xml file for your reference: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>school</artifactId> <version>0.0.1-SNAPSHOT</version> <name>school</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project> Configure PostgreSQL Database Create an application.yml file under /resources folder and add the following content: server: port: 8090 spring: application: name: schools datasource: driver-class-name: org.postgresql.Driver url: jdbc:postgresql://localhost:5432/students username: username password: password jpa: hibernate: ddl-auto: create database: postgresql database-platform: org.hibernate.dialect.PostgreSQLDialect Don’t forget to change the spring.datasource.username and spring.datasource.password as per your PostgreSQL installation.

Also, create a database named schools in PostgreSQL before proceeding to the next section.Domain Layer - School JPA Entity import jakarta.persistence.Entity; import jakarta.persistence.GeneratedValue; import jakarta.persistence.Id; import lombok.*; @Entity @Getter @Setter @AllArgsConstructor @NoArgsConstructor @Builder public class School { @Id @GeneratedValue private Integer id; private String name; private String email; } Repository Layer - SchoolRepository import org.springframework.data.jpa.repository.JpaRepository; public interface SchoolRepository extends JpaRepository<School, Integer> { } Create a DTO Class import lombok.*; import java.util.List; @Getter @Setter @AllArgsConstructor @NoArgsConstructor @Builder public class FullSchoolResponse { private String name; private String email; List<Student> students; } Service Layer - SchoolService import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Service; import java.util.List; @Service @RequiredArgsConstructor public class SchoolService { private final SchoolRepository repository; private final StudentClient client; public void saveSchool(School school) { repository.save(school); } public List<School> findAllSchools() { return repository.findAll(); } } Controller Layer - SchoolController import lombok.RequiredArgsConstructor; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.*; import java.util.List; @RestController @RequestMapping("/api/v1/schools") @RequiredArgsConstructor public class SchoolController { private final SchoolService service; @PostMapping @ResponseStatus(HttpStatus.CREATED) public void save( @RequestBody School school ) { service.saveSchool(school); } @GetMapping public ResponseEntity<List<School>> findAllSchools() { return ResponseEntity.ok(service.findAllSchools()); } } That's completed our school microservice development.3.

Using OpenFeign - Inter-Service Communication Add OpenFeign Dependency <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> Make sure to add spring cloud dependencies and their version.

Here is the complete pom.xml file after adding Spring cloud open feign dependency: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>school</artifactId> <version>0.0.1-SNAPSHOT</version> <name>school</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> <spring-cloud.version>2022.0.2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-openfeign</artifactId> </dependency> <dependency> <groupId>org.postgresql</groupId> <artifactId>postgresql</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project> Enable OpenFeign Client in School Service Next, let's enable OpenFeign Client using @EnableFeignClients annotation:import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.openfeign.EnableFeignClients; @EnableFeignClients @SpringBootApplication public class SchoolApplication { public static void main(String[] args) { SpringApplication.run(SchoolApplication.class, args); } } Note that @EnableFeignClients annotation enables component scanning for interfaces that declare they are Feign clients.Create feign API client After that, we need to have a feign API client with the necessary methods, requests, and responses.Let's create an interface named StudentClient and add the following code: import net,javaguides.school.Student; import org.springframework.cloud.openfeign.FeignClient; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import java.util.List; @FeignClient(name = "student-service", url = "${application.config.students-url}") public interface StudentClient { @GetMapping("/school/{school-id}") List<Student> findAllStudentsBySchool(@PathVariable("school-id") Integer schoolId); } Change SchoolService Class public FullSchoolResponse findSchoolsWithStudents(Integer schoolId) { var school = repository.findById(schoolId) .orElse( School.builder() .name("NOT_FOUND") .email("NOT_FOUND") .build() ); var students = client.findAllStudentsBySchool(schoolId); return FullSchoolResponse.builder() .name(school.getName()) .email(school.getEmail()) .students(students) .build(); } Note that we are using the OpenFeign client to make a REST API call: var students = client.findAllStudentsBySchool(schoolId); Here is the complete StudentService class code: import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Service; import java.util.List; @Service @RequiredArgsConstructor public class SchoolService { private final SchoolRepository repository; private final StudentClient client; public void saveSchool(School school) { repository.save(school); } public List<School> findAllSchools() { return repository.findAll(); } public FullSchoolResponse findSchoolsWithStudents(Integer schoolId) { var school = repository.findById(schoolId) .orElse( School.builder() .name("NOT_FOUND") .email("NOT_FOUND") .build() ); var students = client.findAllStudentsBySchool(schoolId); return FullSchoolResponse.builder() .name(school.getName()) .email(school.getEmail()) .students(students) .build(); } } Create REST API - Retrieve Students by School Id @GetMapping("/with-students/{school-id}") public ResponseEntity<FullSchoolResponse> findAllStudentsBySchoolId( @PathVariable("school-id") Integer schoolId ) { return ResponseEntity.ok(service.findSchoolsWithStudents(schoolId)); } Here is the complete SchoolController class code: import lombok.RequiredArgsConstructor; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.web.bind.annotation.*; import java.util.List; @RestController @RequestMapping("/api/v1/schools") @RequiredArgsConstructor public class SchoolController { private final SchoolService service; @PostMapping @ResponseStatus(HttpStatus.CREATED) public void save( @RequestBody School school ) { service.saveSchool(school); } @GetMapping public ResponseEntity<List<School>> findAllSchools() { return ResponseEntity.ok(service.findAllSchools()); } @GetMapping("/with-students/{school-id}") public ResponseEntity<FullSchoolResponse> findAllStudentsBySchoolId( @PathVariable("school-id") Integer schoolId ) { return ResponseEntity.ok(service.findSchoolsWithStudents(schoolId)); } } 4.

Discovery In this section, we will learn how to use SpringCloud Netflix Eureka for Service Registry and Discovery. Create Spring Boot Project Let's create a Spring boot project using the spring initializr.

Refer to the below screenshot to enter details while creating the spring boot application using the spring initializr: Here is the complete pom.xml file for your reference: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>discovery</artifactId> <version>0.0.1-SNAPSHOT</version> <name>discovery</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> <spring-cloud.version>2022.0.2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>netflix-candidates</id> <name>Netflix Candidates</name> <url>https://artifactory-oss.prod.netflix.net/artifactory/maven-oss-candidates</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project> Add @EnableEurekaServer annotation import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer; @EnableEurekaServer @SpringBootApplication public class DiscoveryApplication { public static void main(String[] args) { SpringApplication.run(DiscoveryApplication.class, args); } } Configure the Eureka Server in an application.yml File eureka: instance: hostname: localhost client: register-with-eureka: false fetch-registry: false service-url: defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/ server: port: 8761 Registering Student Microservice as Eureka Client <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> eureka: instance: hostname: localhost client: service-url: defaultZone: http://localhost:8761/eureka Registering School Microservice as Eureka Client <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> eureka: instance: hostname: localhost client: service-url: defaultZone: http://localhost:8761/eureka Run Discovery Service With this configuration in place, start the discovery service and visit http://localhost:8761: 5.

API Gateway In this section, we will learn how to set up an API gateway into our microservices project using the Spring Cloud Gateway library. Spring Cloud Gateway provides a library for building an API Gateway on top of Spring WebFlux. Spring Cloud Gateway aims to provide a simple, yet effective way to route to APIs and provide cross-cutting concerns to them such as security, monitoring/metrics, and resiliency. Create Spring Boot Project Let's create a Spring boot project using the spring initializr.

Refer to the below screenshot to enter details while creating the spring boot application using the spring initializr: Here is the complete pom.xml file for your reference: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>gateway</artifactId> <version>0.0.1-SNAPSHOT</version> <name>gateway</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> <spring-cloud.version>2022.0.2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-gateway</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>netflix-candidates</id> <name>Netflix Candidates</name> <url>https://artifactory-oss.prod.netflix.net/artifactory/maven-oss-candidates</url> <snapshots> <enabled>false</enabled> </snapshots> </repository> </repositories> </project> Configuring API Gateway Routes With Spring Cloud Gateway eureka: client: register-with-eureka: false server: port: 8222 spring: application: name: gateway cloud: gateway: discovery: locator: enabled: true routes: - id: students uri: http://localhost:8090 predicates: - Path=/api/v1/students/** - id: schools uri: http://localhost:8070 predicates: - Path=/api/v1/schools/** management: tracing: sampling: probability: 1.0 6.

Config Server In this section, we will learn how to create a Spring cloud config server to centralize configurations of the Spring boot microservices. Well, we will keep the configuration files of all the microservices in a local central place. Create Spring Boot Project Let's create a Spring boot project using the spring initializr.

Refer to the below screenshot to enter details while creating the spring boot application using the spring initializr: Here is the pom.xml file for your reference: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.0.6</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>net.javaguides</groupId> <artifactId>config-server</artifactId> <version>0.0.1-SNAPSHOT</version> <name>config-server</name> <description>Demo project for Spring Boot</description> <properties> <java.version>17</java.version> <spring-cloud.version>2022.0.2</spring-cloud.version> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-config-server</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> Enable Config Server using @EnableConfigServer Annotation To make our Spring Boot application a Spring Cloud Config Server, we just need to add the @EnableConfigServer annotation to the main entry point class: import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.cloud.config.server.EnableConfigServer; @EnableConfigServer @SpringBootApplication public class ConfigServerApplication { public static void main(String[] args) { SpringApplication.run(ConfigServerApplication.class, args); } } Configure the Location for Centralized Configuration Now, let's configure the location of the local repository where we are going to store all our configuration files in the application.properties file: server: port: 8888 spring: profiles: active: native application: name: config-server cloud: config: server: native: search-locations: classpath:/configurations Under /resources/configurations folder and keep all the configuration files: students.yml eureka: instance: hostname: localhost client: service-url: defaultZone: http://localhost:8761/eureka server: port: 8090 spring: application: name: students datasource: driver-class-name: org.postgresql.Driver url: jdbc:postgresql://localhost:5432/students username: username password: password jpa: hibernate: ddl-auto: create database: postgresql database-platform: org.hibernate.dialect.PostgreSQLDialect management: tracing: sampling: probability: 1.0 School.yml eureka: instance: hostname: localhost client: service-url: defaultZone: http://localhost:8761/eureka server: port: 8070 spring: application: name: schools datasource: driver-class-name: org.postgresql.Driver url: jdbc:postgresql://localhost:5432/schools username: username password: password jpa: hibernate: ddl-auto: create database: postgresql database-platform: org.hibernate.dialect.PostgreSQLDialect application: config: students-url: http://localhost:8222/api/v1/students management: tracing: sampling: probability: 1.0 discovery.yml eureka: instance: hostname: localhost client: register-with-eureka: false fetch-registry: false service-url: defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/ server: port: 8761 gateway.yml eureka: client: register-with-eureka: false server: port: 8222 spring: application: name: gateway cloud: gateway: discovery: locator: enabled: true routes: - id: students uri: http://localhost:8090 predicates: - Path=/api/v1/students/** - id: schools uri: http://localhost:8070 predicates: - Path=/api/v1/schools/** management: tracing: sampling: probability: 1.0 Refactor the Student Service to use Config Server Add the below dependency to the student service pom.xml file to use the config server: <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> Configure config server URL in student service spring: application: name: students config: import: optional:configserver:http://localhost:8888 Refactor the School Service to use Config Server Add the below dependency to the school service pom.xml file to use the config server: <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> Configure config server URL in School service spring: application: name: students config: import: optional:configserver:http://localhost:8888 Refactor the Discovery Service to use Config Server Add the below dependency to the discovery service pom.xml file to use the config server: <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> Configure config server URL in Discovery service spring: application: name: students config: import: optional:configserver:http://localhost:8888 Refactor the Gateway Service to use Config Server Add the below dependency to the gateway service pom.xml file to use the config server: <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-config</artifactId> </dependency> Configure config server URL in Gateway service spring: application: name: students config: import: optional:configserver:http://localhost:8888 Demo Conclusion In this tutorial, we learned how to build a step-by-step microservice project using Spring Boot 3, Spring Cloud, and the PostgreSQL database.

Credits You can check out the complete source on the GitHub repository: https://github.com/ali-bouali/springboot-3-micro-service-demo. Video tutorial available here: Microservices tutorial with Spring boot 3 | Full course My Top and Bestseller Udemy Courses. The sale is going on with a 70 - 80% discount.

The discount coupon has been added to each course below: Build REST APIs with Spring Boot 4, Spring Security 7, and JWT [NEW] Learn Apache Maven with IntelliJ IDEA and Java 25 ChatGPT + Generative AI + Prompt Engineering for Beginners Spring 7 and Spring Boot 4 for Beginners (Includes 8 Projects) Available in Udemy for Business Building Real-Time REST APIs with Spring Boot - Blog App Available in Udemy for Business Building Microservices with Spring Boot and Spring Cloud Available in Udemy for Business Java Full-Stack Developer Course with Spring Boot and React JS Available in Udemy for Business Build 5 Spring Boot Projects with Java: Line-by-Line Coding Testing Spring Boot Application with JUnit and Mockito Available in Udemy for Business Spring Boot Thymeleaf Real-Time Web Application - Blog App Available in Udemy for Business Master Spring Data JPA with Hibernate Available in Udemy for Business Spring Boot + Apache Kafka Course - The Practical Guide Available in Udemy for Business Comments Post a Comment Leave Comment

People Also Asked

• Java Spring Boot Microservices Example - Step by Step Guide
• Java + Spring Boot + Microservices Example - Step by Step Guide
• A Step-by-Step Guide to Implementing Spring Boot for ...
• Microservices Project using Spring Boot - Java Guides
• Building Your First Microservice System with Spring Boot: A ...
• JavaSpringBootMicroservices- photos and vectors
• Adventures inMicroservices: Crafting a New Kingdom | Medium
• Building Better Microservices with Spring Boot 3