Thursday, August 18, 2022

Multiple Data Sources in Spring Boot 3 with Java 21


In this blog post, we'll explore the configuration and setup for a Spring Boot 3 application with Java 21 that uses multiple data sources. This setup is useful when dealing with databases of different types, such as MySQL, Oracle, and PostgreSQL. 






Technology


  • Spring Boot 3.2.0
  • Java 21 (Zulu)
  • Docker Compose
  • Maven 
  • IntelliJ IDEA  2023.3.1 Community 
  • Postman


Project Structure


multiple-data-sources-jpa
|-- src
|   |-- main
|       |-- java
|           |-- com
|               |-- henry
|                   |-- configuration
|                   |-- model
|                   |-- repository
|                   |-- service
|                   |-- controller
|-- src
|   |-- test
|       |-- java
|           |-- com
|               |-- henry
|                   |-- ...
|-- pom.xml


Application.yaml Configuration



The application file contains configuration deatils for each data source, including URLs, usernames, passowrds, and driver class names.


server:
  port: 9000
  servlet:
    context-path: /

spring:
  datasource:
    mysql:
      url: jdbc:mysql://localhost:3306/test_db?allowPublicKeyRetrieval=true
      username: test
      password: test_pass
      driverClassName: com.mysql.cj.jdbc.Driver
      ddlAuto: create-drop
    postgres:
      url: jdbc:postgresql:postgre_test
      username: postgre_test
      password: postgre_test
      driverClassName: org.postgresql.Driver
      ddlAuto: create-drop
    oracle:
      url: jdbc:oracle:thin:@//localhost:1521/xe
      username: system
      password: oracle
      driverClassName: oracle.jdbc.OracleDriver
      ddlAuto: update


Configuration Classes


We've created configuration classes for each data source - MysqlConfig, PostgreConfig, and OracleConfig:


package com.henry.configuration;

import com.henry.record.OracleRecord;
import com.henry.record.PostgreRecord;
import com.henry.record.MysqlRecord;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

import lombok.Data;

@Component
@ConfigurationProperties("spring.datasource")
@Data
public class DataSourceProperties {
   private MysqlRecord mysql;
   private PostgreRecord postgres;
   private OracleRecord oracle;

}


package com.henry.configuration;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;

import javax.naming.NamingException;
import javax.sql.DataSource;
import java.util.Properties;

@Configuration
@EnableJpaRepositories(
        basePackages = "com.henry.repository.user",
        entityManagerFactoryRef = "userEntityManager",
        transactionManagerRef = "userTransactionManager"
)
public class MysqlConfig {

    @Autowired
    private DataSourceProperties dsProperties;

    @Bean
    @Primary
    public LocalContainerEntityManagerFactoryBean userEntityManager()
            throws NamingException {
        LocalContainerEntityManagerFactoryBean em
                = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(userDataSource());
        em.setPackagesToScan("com.henry.model.user");

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(userHibernateProperties());

        return em;
    }

    @Bean
    @Primary
    public DataSource userDataSource() throws IllegalArgumentException, NamingException {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(dsProperties.getMysql().driverClassName());
        dataSource.setUrl(dsProperties.getMysql().url());
        dataSource.setUsername(dsProperties.getMysql().username());
        dataSource.setPassword(dsProperties.getMysql().password());

        return dataSource;
    }

    private Properties userHibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.hbm2ddl.auto",dsProperties.getMysql().ddlAuto());

        return properties;
    }

    @Primary
    @Bean
    public PlatformTransactionManager userTransactionManager() throws NamingException {
        final JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(userEntityManager().getObject());
        return transactionManager;
    }
}

package com.henry.configuration;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;

import javax.naming.NamingException;
import javax.sql.DataSource;
import java.util.Properties;

@Configuration
@EnableJpaRepositories(
        basePackages = "com.henry.repository.brand",
        entityManagerFactoryRef = "brandEntityManager",
        transactionManagerRef = "brandTransactionManager"
)
public class OracleConfig {

    @Autowired
    private DataSourceProperties dsProperties;

    @Bean
    public LocalContainerEntityManagerFactoryBean brandEntityManager()
            throws NamingException {
        LocalContainerEntityManagerFactoryBean em
                = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(brandDataSource());
        em.setPackagesToScan("com.henry.model.brand");

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(brandHibernateProperties());

        return em;
    }

    @Bean
    public DataSource brandDataSource() throws IllegalArgumentException, NamingException {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(dsProperties.getOracle().driverClassName());
        dataSource.setUrl(dsProperties.getOracle().url());
        dataSource.setUsername(dsProperties.getOracle().username());
        dataSource.setPassword(dsProperties.getOracle().password());

        return dataSource;
    }

    private Properties brandHibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.hbm2ddl.auto", dsProperties.getOracle().ddlAuto());

        return properties;
    }


    @Bean
    public PlatformTransactionManager brandTransactionManager() throws NamingException {
        final JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(brandEntityManager().getObject());
        return transactionManager;
    }
}

package com.henry.configuration;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.JpaVendorAdapter;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;

import javax.naming.NamingException;
import javax.sql.DataSource;
import java.util.Properties;

@Configuration
@EnableJpaRepositories(
        basePackages = "com.henry.repository.company",
        entityManagerFactoryRef = "companyEntityManager",
        transactionManagerRef = "companyTransactionManager"
)
public class PostgreConfig {

    @Autowired
    private DataSourceProperties dsProperties;

    @Bean
    public LocalContainerEntityManagerFactoryBean companyEntityManager()
            throws NamingException {
        LocalContainerEntityManagerFactoryBean em
                = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(companyDataSource());
        em.setPackagesToScan("com.henry.model.company");

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(companyHibernateProperties());

        return em;
    }

    @Bean
    public DataSource companyDataSource() throws IllegalArgumentException, NamingException {
        DriverManagerDataSource dataSource = new DriverManagerDataSource();
        dataSource.setDriverClassName(dsProperties.getPostgres().driverClassName());
        dataSource.setUrl(dsProperties.getPostgres().url());
        dataSource.setUsername(dsProperties.getPostgres().username());
        dataSource.setPassword(dsProperties.getPostgres().password());

        return dataSource;
    }

    private Properties companyHibernateProperties() {
        Properties properties = new Properties();
        properties.put("hibernate.hbm2ddl.auto", dsProperties.getPostgres().ddlAuto());

        return properties;
    }

    @Bean
    public PlatformTransactionManager companyTransactionManager() throws NamingException {
        final JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(companyEntityManager().getObject());
        return transactionManager;
    }
}


Record Classes


To encapsulate the configuration properties for each data source, we've defined record classes - MysqlRecord, PostgreRecord, and OracleRecord:


package com.henry.record;

public record MysqlRecord(String url, String username, String password, String driverClassName,String ddlAuto) {
}

package com.henry.record;

public record OracleRecord(String url, String username, String password, String driverClassName,String ddlAuto) {
}


package com.henry.record;

public record PostgreRecord(String url, String username, String password, String driverClassName,String ddlAuto) {
}

Repositories


Repository interfaces extend the CrudRepository for each entity (Brand, Company, User):


package com.henry.repository.brand;

import com.henry.model.brand.Brand;
import org.springframework.data.repository.CrudRepository;

public interface BrandRepository extends CrudRepository<Brand,Long> {
}

package com.henry.repository.company;

import com.henry.model.company.Company;
import org.springframework.data.repository.CrudRepository;

public interface CompanyRepository extends CrudRepository<Company,Long> {
}

package com.henry.repository.user;

import com.henry.model.user.User;
import org.springframework.data.repository.CrudRepository;

public interface UserRepository extends CrudRepository<User,Long> {
}

Services


Service classes (BrandServiceImpl, CompanyServiceImpl, UserServiceImpl) implement a common interface (DefaultService) for generic CRUD operations:

package com.henry.service;

public sealed interface DefaultService<T, G> permits UserServiceImpl, CompanyServiceImpl, BrandServiceImpl {

    T save(T obj);
    Iterable<T>  findAll();
    T findById(G id);
}

package com.henry.service;

import com.henry.model.brand.Brand;
import com.henry.repository.brand.BrandRepository;
import org.springframework.stereotype.Service;

@Service
public final class BrandServiceImpl implements DefaultService<Brand, Long> {

    private final BrandRepository brandRepository;

    public BrandServiceImpl(BrandRepository brandRepository) {
        this.brandRepository = brandRepository;
    }


    @Override
    public Brand save(Brand obj) {
        return brandRepository.save(obj);
    }

    @Override
    public Iterable<Brand> findAll() {
        return brandRepository.findAll();
    }

    @Override
    public Brand findById(Long id) {
        return brandRepository.findById(id).get();
    }
}

package com.henry.service;

import com.henry.model.company.Company;
import com.henry.repository.company.CompanyRepository;
import org.springframework.stereotype.Service;

@Service
public final class CompanyServiceImpl implements DefaultService<Company, Long> {

    private final CompanyRepository companyRepository;

    public CompanyServiceImpl(CompanyRepository companyRepository) {
        this.companyRepository = companyRepository;
    }

    @Override
    public Company save(Company obj) {
        return companyRepository.save(obj);
    }

    @Override
    public Iterable<Company> findAll() {
        return companyRepository.findAll();
    }

    @Override
    public Company findById(Long id) {
        return companyRepository.findById(id).get();
    }
}

package com.henry.service;

import com.henry.model.user.User;
import com.henry.repository.user.UserRepository;
import org.springframework.stereotype.Service;

@Service
public final class UserServiceImpl implements DefaultService<User,Long> {

    private final UserRepository userRepository;

    public UserServiceImpl(UserRepository userRepository) {
        this.userRepository = userRepository;
    }

    @Override
    public User save(User obj) {
        return userRepository.save(obj);
    }

    @Override
    public Iterable<User> findAll() {
        return userRepository.findAll();
    }

    @Override
    public User findById(Long id) {
        return userRepository.findById(id).get();
    }
}

REST Controllers


REST controllers (BrandController, CompanyController, UserController) handle HTTP requests for creating entities:


package com.henry.controller;

import com.henry.model.brand.Brand;
import com.henry.service.DefaultService;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/v3")
public class BrandController {

    private final DefaultService<Brand, Long> defaultService;

    public BrandController(DefaultService<Brand, Long> defaultService) {
        this.defaultService = defaultService;
    }

    @PostMapping("/brands")
    public Brand createEmployee(@RequestBody Brand brand) {
        return defaultService.save(brand);
    }

}

package com.henry.controller;

import com.henry.model.company.Company;
import com.henry.service.DefaultService;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/v2")
public class CompanyController {

    private final DefaultService<Company,Long> defaultService;

    public CompanyController(DefaultService<Company, Long> defaultService) {
        this.defaultService = defaultService;
    }

    @PostMapping("/companies")
    public Company createEmployee(@RequestBody Company company) {
        return defaultService.save(company);
    }
}

package com.henry.controller;

import com.henry.model.user.User;
import com.henry.service.DefaultService;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api/v1")
public class UserController {

    private final DefaultService<User,Long> defaultService;

    public UserController(DefaultService<User, Long> defaultService) {
        this.defaultService = defaultService;
    }

    @PostMapping("/users")
    public User createEmployee(@RequestBody User user) {
        return defaultService.save(user);
    }
}


Test Classes


JUnit test classes (BrandServiceTest, CompanyServiceTest, UserServiceTest) use Mockito for mocking dependencies:


package com.henry;

import com.google.common.collect.Iterables;
import com.henry.model.brand.Brand;
import com.henry.repository.brand.BrandRepository;
import com.henry.service.BrandServiceImpl;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import java.util.Arrays;
import java.util.Optional;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

@ExtendWith(MockitoExtension.class)
class BrandServiceTest {

    @Mock
    private BrandRepository brandRepository;

    @InjectMocks
    private BrandServiceImpl brandService;

    @Test
    void testSaveBrand() {
        Brand brand = Brand.builder()
                .id(1L)
                .name("Test Brand")
                .build();

        when(brandRepository.save(any())).thenReturn(brand);

        Brand saved = brandService.save(brand);

        assertEquals(brand, saved);
        verify(brandRepository).save(any());
    }

    @Test
    void testFindAllBrands() {
        Brand brand1 = Brand.builder()
                .id(1L)
                .name("Test Brand")
                .build();
        Brand brand2 = Brand.builder()
                .id(2L)
                .name("Demo Brand")
                .build();

        when(brandRepository.findAll()).thenReturn(Arrays.asList(brand1, brand2));

        Iterable<Brand> result = brandService.findAll();

        assertEquals(2, Iterables.size(result));
        verify(brandRepository).findAll();
    }

    @Test
    void testFindBrandById() {
        Brand brand = Brand.builder()
                .id(1L)
                .name("Demo Brand")
                .build();

        when(brandRepository.findById(1L)).thenReturn(Optional.of(brand));

        Brand result = brandService.findById(1L);

        assertEquals(brand, result);
        verify(brandRepository).findById(1L);
    }
}
package com.henry;

import com.google.common.collect.Iterables;
import com.henry.model.company.Company;
import com.henry.repository.company.CompanyRepository;
import com.henry.service.CompanyServiceImpl;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import java.util.Arrays;
import java.util.Optional;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

@ExtendWith(MockitoExtension.class)
class CompanyServiceTest {

    @Mock
    private CompanyRepository companyRepository;

    @InjectMocks
    private CompanyServiceImpl companyService;

    @Test
    void testSaveCompany() {
        Company company =
                Company.builder()
                        .id(1L)
                        .name("Test Corp")
                        .build();

        when(companyRepository.save(any())).thenReturn(company);

        Company saved = companyService.save(company);

        assertEquals(company, saved);
        verify(companyRepository).save(any());
    }

    @Test
    void testFindAllCompanies() {
        Company comp1 = Company.builder()
                .id(1L)
                .name("Test Corp")
                .build();
        Company comp2 = Company.builder()
                .id(2L)
                .name("Demo Corp")
                .build();

        when(companyRepository.findAll()).thenReturn(Arrays.asList(comp1, comp2));

        Iterable<Company> result = companyService.findAll();


        assertEquals(2, Iterables.size(result));
        verify(companyRepository).findAll();
    }

    @Test
    void testFindCompanyById() {
        Company company = Company.builder()
                .id(1L)
                .name("Test Corp")
                .build();

        when(companyRepository.findById(1L)).thenReturn(Optional.of(company));

        Company result = companyService.findById(1L);

        assertEquals(company, result);
        verify(companyRepository).findById(1L);
    }
}
package com.henry;

import com.google.common.collect.Iterables;
import com.henry.model.user.User;
import com.henry.repository.user.UserRepository;
import com.henry.service.UserServiceImpl;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import java.util.Arrays;
import java.util.Optional;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

@ExtendWith(MockitoExtension.class)
public class UserServiceTest {

    @Mock
    private UserRepository userRepository;

    @InjectMocks
    private UserServiceImpl userService;

    @Test
    public void saveUser_shouldPersistUser() {
/**

 int x = 10;
 int y = 20;
 String result = STR."\{x} + \{y} = \{x + y}";
 string templates are a preview feature and are disabled by default.
 Are string templates supported yet? - IntelliJ support - JetBrains
 https://intellij-support.jetbrains.com/hc/en-us/community/posts/13451540436114-Are-string-templates-supported-yet-
 **/

        // Create a User
        User user = User.builder()
                .id(1L)
                .name("John")
                .lastName("Doe")
                .build();

        when(userRepository.save(any())).thenReturn(user);

        User saved = userService.save(user);

        assertEquals(user, saved);
        verify(userRepository).save(any());
    }

    @Test
    void testFindAllUsers() {
        User user1 = User.builder()
                .id(1L)
                .name("John")
                .lastName("Doe")
                .build();
        User user2 = User.builder()
                .id(2L)
                .name("John")
                .lastName("Doe")
                .build();

        when(userRepository.findAll()).thenReturn(Arrays.asList(user1, user2));

        Iterable<User> result = userService.findAll();

        assertEquals(2, Iterables.size(result));
        verify(userRepository).findAll();
    }

    @Test
    void testFindUserById() {
        User user = User.builder()
                .id(1L)
                .name("John")
                .lastName("Doe")
                .build();

        when(userRepository.findById(1L)).thenReturn(Optional.of(user));

        User result = userService.findById(1L);

        assertEquals(user, result);
        verify(userRepository).findById(1L);
    }
}


Maven Configuration


The pom.xml file manages project dependencies and build configuration:


<?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>3.2.0</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.henry</groupId>
	<artifactId>multiple-data-sources-jpa</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>multiple-data-sources-jpa</name>
	<description>Demo project multiple data sources jpa</description>
	<properties>
		<java.version>21</java.version>
	</properties>
	<dependencies>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
			<exclusions>
				<!-- Exclude the Tomcat dependency -->
				<exclusion>
					<groupId>org.springframework.boot</groupId>
					<artifactId>spring-boot-starter-tomcat</artifactId>
				</exclusion>
			</exclusions>
		</dependency>
		<!-- Use Jetty instead -->
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-jetty</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>

		<!-- MARIADB Connector -->

		<dependency>
			<groupId>org.mariadb.jdbc</groupId>
			<artifactId>mariadb-java-client</artifactId>
		</dependency>

		<!-- Mysql Connector -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.30</version>
		</dependency>

		<!-- ORACLE database driver -->
		<!-- https://mvnrepository.com/artifact/oracle/ojdbc6 -->
		<dependency>
			<groupId>com.oracle</groupId>
			<artifactId>ojdbc6</artifactId>
			<version>11.2.0.4</version>
		</dependency>

		<!-- POSTGRESQL database driver -->
		<dependency>
			<groupId>org.postgresql</groupId>
			<artifactId>postgresql</artifactId>
			<scope>runtime</scope>
		</dependency>

		<dependency>
			<groupId>com.google.guava</groupId>
			<artifactId>guava</artifactId>
			<version>31.0.1-jre</version>
		</dependency>

		<!-- https://mvnrepository.com/artifact/org.antlr/stringtemplate
		<dependency>
			<groupId>org.antlr</groupId>
			<artifactId>stringtemplate</artifactId>
			<version>4.0.2</version>
		</dependency>
		-->

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
		</dependency>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<configuration>
					<source>21</source>
					<target>21</target>
					<compilerArgs>--enable-preview</compilerArgs>
				</configuration>
			</plugin>
		</plugins>
	</build>

</project>


Environment Setup with Docker Compose


To simplify the setup of your application's environment, you can use Docker Compose. Below is a docker-compose-multiple-db.yml file that defines services for Oracle, PostgreSQL, and MySQL databases:

version: '3'
services:
  oracle:
    image: pengbai/docker-oracle-xe-11g-r2
    ports:
      - "1521:1521"
      - "8080:8080"
    shm_size: 1g

  postgres:
    image: postgres:14.1
    container_name: postgre_test
    environment:
      POSTGRES_USER: postgre_test
      POSTGRES_PASSWORD: postgre_test
      POSTGRES_DB: postgre_test
    ports:
      - "5432:5432"

  mysql:
    image: mysql/mysql-server:latest
    container_name: mysql-docker-container
    environment:
      MYSQL_ROOT_PASSWORD: mypass
      MYSQL_DATABASE: test_db
      MYSQL_USER: test
      MYSQL_PASSWORD: test_pass
    ports:
      - "3306:3306"

Run command:

 
docker-compose -f docker-compose-multiple-db.yml up -d



Only for oracle:

mvn install:install-file "-Dfile=path/to/your/ojdbc6.jar" "-DgroupId=com.oracle" "-DartifactId=ojdbc6" "-Dversion=11.2.0.4" "-Dpackaging=jar" "-DgeneratePom=true"


Run & Test


Run Spring Boot application with command: by console, IntelliJ etc.


mvn test -Dtest=UserServiceTest

mvn test -Dtest=BrandServiceTest

mvn test -Dtest=CompanyServiceTest







Run locally: mvn spring-boot:run





POST
http://localhost:9000/api/v1/users

{
    "name""henry",
    "lastName""x"
}







POST
http://localhost:9000/api/v2/companies
{
    "name""company1"
}











POST
http://localhost:9000/api/v3/brands

{
    "name""Demo Brand"
}












Source Code


Here on GitHub.










Tuesday, August 9, 2022

Spring Boot2 + Reactive Spring Data + Reactive Elasticsearch + CRUD

Spring Boot + Reactive Spring Data + Reactive Elasticsearch example

Elasticsearch: 

By official documentation Elasticsearch is a distributed, free and open search and analytics engine for all types of data, including textual, numerical, geospatial, structured, and unstructured. Elasticsearch is built on Apache Lucene and was first released in 2010 by Elasticsearch N.V. (now known as Elastic).

Technology

  • Spring Boot 2.7.2
  • Java 17 (Zulu)
  • Docker
  • Maven 
  • Elasticsearch 7.17.5
  • IntelliJ IDEA 
  • Postman

Project Structure


























Configuration Spring Boot project 


pom.xml


<?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>2.7.2</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.henry</groupId>
<artifactId>SpringDataElasticsearch</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>SpringDataElasticsearch</name>
<description>Integration SpringData + Elasticsearch</description>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-elasticsearch</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-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
<groupId>org.hsqldb</groupId>
<artifactId>hsqldb</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<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>
</plugin>
</plugins>
</build>

</project>


application.yml: Configuration reactive elasticsearch 


server:
port: 9000
servlet:
context-path: /
spring:
data:
elasticsearch:
client:
reactive:
endpoints: localhost:9200
elasticsearch:
rest:
uris: http://localhost:9200

Model


package com.henry.SpringDataElasticsearch.model;

import org.springframework.data.elasticsearch.annotations.Document;
import org.springframework.data.annotation.Id;

@Document(indexName = "users")
public class User {

@Id
private Long id;
private String name;
private String lastName;

public Long getId() {
return id;
}

public void setId(Long id) {
this.id = id;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public String getLastName() {
return lastName;
}

public void setLastName(String lastName) {
this.lastName = lastName;
}

@Override
public String toString() {
return "Users{" +
"id=" + id +
", name='" + name + '\'' +
", lastName='" + lastName + '\'' +
'}';
}
}

Repository


package com.henry.SpringDataElasticsearch.repository;

import com.henry.SpringDataElasticsearch.model.User;
import org.springframework.data.repository.reactive.ReactiveCrudRepository;
import org.springframework.stereotype.Repository;
import reactor.core.publisher.Flux;

@Repository
public interface UserRepository extends ReactiveCrudRepository<User, Long> {

Flux<User> findByName(String name);
}

Service


package com.henry.SpringDataElasticsearch.service;

import com.henry.SpringDataElasticsearch.model.User;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

public interface UserService {
Mono<User> save(User user);

Mono<User> update(Long id, User user);

Mono<Void> delete(Long id);

Mono<User> findOne(Long id);

Flux<User> findAll();

Flux<User> findByName(String name);
}

ServiceImpl


package com.henry.SpringDataElasticsearch.service.impl;

import com.henry.SpringDataElasticsearch.model.User;
import com.henry.SpringDataElasticsearch.repository.UserRepository;
import com.henry.SpringDataElasticsearch.service.UserService;
import org.springframework.stereotype.Service;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

@Service
public class UserServiceImpl implements UserService {

private final UserRepository userRepository;

public UserServiceImpl(UserRepository userRepository) {
this.userRepository = userRepository;
}

@Override
public Mono<User> save(User user) {
return userRepository.save(user);
}

@Override
public Mono<User> update(Long id, User user) {
return userRepository.findById(id)
.flatMap(u -> {
u.setName(user.getName());
u.setLastName(user.getLastName());
return userRepository.save(u);
});
}

@Override
public Mono<Void> delete(Long id) {
var del = userRepository.deleteById(id);
return del;
}

@Override
public Mono<User> findOne(Long id) {
return userRepository.findById(id);
}

@Override
public Flux<User> findAll() {
return userRepository.findAll();
}

@Override
public Flux<User> findByName(String name) {
return userRepository.findByName(name);
}
}

Controller


package com.henry.SpringDataElasticsearch.controller;

import com.henry.SpringDataElasticsearch.model.User;
import com.henry.SpringDataElasticsearch.service.UserService;
import org.springframework.web.bind.annotation.*;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

@RestController
@RequestMapping("/users")
public class UserController {

private final UserService userService;

public UserController(UserService userService) {
this.userService = userService;
}

@PostMapping("/save")
public Mono<User> add(@RequestBody User user) {
return userService.save(user);
}

@PutMapping("/update/{id}")
public Mono<User> update(@PathVariable Long id, @RequestBody User user) {
return userService.update(id, user);
}

@GetMapping("/findOne/{id}")
public Mono<User> findOne(@PathVariable Long id) {
return userService.findOne(id);
}

@GetMapping("/all")
public Flux<User> findAll() {
return userService.findAll();
}

@GetMapping("/findByName/{name}")
public Flux<User> findByName(@PathVariable String name) {
return userService.findByName(name);
}

@DeleteMapping("/delete/{id}")
public Mono<Void> delete(@PathVariable Long id) {
return userService.delete(id);
}

}

Downloading and installing Elasticsearch


docker run -d --name elasticsearch -p 9200:9200 -e "discovery.type=single-node" elasticsearch:7.17.5


Run & Test


Run Spring Boot application with command: mvn spring-boot:run. by console, IntelliJ etc.


POST
localhost:9000/users/save















PUT
localhost:9000/users/update/1
















GET
localhost:9000/users/all


















localhost:9000/users/findByName/henry
















DELETE
localhost:9000/users/delete/1












Basic examples  retrieves documents in Elasticsearch are represented in JSON format.

localhost:9200/_search?q=Henry





















http://localhost:9200/_search?q=lastName:user




















Source Code


Here on GitHub.






References.

https://www.elastic.co/what-is/elasticsearch
https://www.elastic.co/blog/a-practical-introduction-to-elasticsearch
https://www.springcloud.io/post/2022-03/getting-started-with-spring-webflux/#gsc.tab=0
https://piotrminkowski.com/2019/10/25/reactive-elasticsearch-with-spring-boot/
https://mkyong.com/spring-boot/spring-boot-spring-data-elasticsearch-example/
https://www.youtube.com/watch?v=bYiNlCaaRiI
https://www.youtube.com/watch?v=rfjsaccL_e0
https://www.youtube.com/watch?v=uSFNaYlc5ek

Multiple Data Sources in Spring Boot 3 with Java 21

  In this blog post, we'll explore the configuration and setup for a Spring Boot 3 application with Java 21 that uses multiple data sour...