BAEL-6525: changes for Set up Multiple Database with Flyway in Spring Boot

spring-boot-modules/flyway-multidb-springboot/pom.xml

@@ -0,0 +1,51 @@
+<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>flyway-multidb-springboot</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>flyway-multidb-springboot</name>
+    <description>This is simple boot application for Spring boot multiple flyway database</description>
+
+    <parent>
+        <groupId>com.baeldung.spring-boot-modules</groupId>
+        <artifactId>spring-boot-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-jpa</artifactId>
+            <version>3.2.3</version>
+        </dependency>
+        <dependency>
+            <groupId>org.flywaydb</groupId>
+            <artifactId>flyway-core</artifactId>
+            <version>9.22.3</version>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>2.2.224</version>
+            <scope>runtime</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <version>3.2.3</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/FlywayMultidbApplication.java

@@ -0,0 +1,13 @@
+package com.baeldung;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication(scanBasePackages = "com.baeldung")
+public class FlywayMultidbApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(FlywayMultidbApplication.class, args);
+	}
+
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/config/ProductDbConfig.java

@@ -0,0 +1,62 @@
+package com.baeldung.config;
+
+import jakarta.annotation.PostConstruct;
+import javax.sql.DataSource;
+import java.util.Map;
+import jakarta.persistence.EntityManagerFactory;
+import org.flywaydb.core.Flyway;
+import org.springframework.boot.jdbc.DataSourceBuilder;
+import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
+import org.springframework.context.annotation.*;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+import org.springframework.orm.jpa.*;
+import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+@Configuration
+@EnableTransactionManagement
+@EnableJpaRepositories(
+        basePackages = "com.baeldung.repository.product",
+        entityManagerFactoryRef = "productEntityManagerFactory",
+        transactionManagerRef = "productTransactionManager"
+)
+public class ProductDbConfig {
+
+    @Bean
+    public DataSource productDataSource() {
+        return DataSourceBuilder.create()
+                .url("jdbc:h2:mem:productdb")
+                .username("sa")
+                .password("")
+                .driverClassName("org.h2.Driver")
+                .build();
+    }
+
+    @Bean
+    public LocalContainerEntityManagerFactoryBean productEntityManagerFactory(
+            EntityManagerFactoryBuilder builder) {
+
+        return builder
+                .dataSource(productDataSource())
+                .packages("com.baeldung.entity")
+                .persistenceUnit("productPU")
+                .properties(Map.of("hibernate.hbm2ddl.auto", "none"))
+                .build();
+    }
+
+    @Bean
+    public PlatformTransactionManager productTransactionManager(
+            EntityManagerFactory productEntityManagerFactory) {
+
+        return new JpaTransactionManager(productEntityManagerFactory);
+    }
+
+    @PostConstruct
+    public void migrateProductDb() {
+        Flyway.configure()
+                .dataSource(productDataSource())
+                .locations("classpath:db/migration/productdb")
+                .load()
+                .migrate();
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/config/UserDbConfig.java

@@ -0,0 +1,69 @@
+package com.baeldung.config;
+
+import jakarta.annotation.PostConstruct;
+import jakarta.persistence.EntityManagerFactory;
+import org.flywaydb.core.Flyway;
+import java.util.Map;
+import org.springframework.boot.jdbc.DataSourceBuilder;
+import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
+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.orm.jpa.JpaTransactionManager;
+import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
+import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.annotation.EnableTransactionManagement;
+
+import javax.sql.DataSource;
+
+@Configuration
+@EnableTransactionManagement
+@EnableJpaRepositories(
+        basePackages = "com.baeldung.repository.user",
+        entityManagerFactoryRef = "userEntityManagerFactory",
+        transactionManagerRef = "userTransactionManager"
+)
+public class UserDbConfig {
+
+    @Bean
+    @Primary
+    public DataSource userDataSource() {
+        return DataSourceBuilder.create()
+                .url("jdbc:h2:mem:userdb")
+                .username("sa")
+                .password("")
+                .driverClassName("org.h2.Driver")
+                .build();
+    }
+
+    @Bean
+    @Primary
+    public LocalContainerEntityManagerFactoryBean userEntityManagerFactory(
+            EntityManagerFactoryBuilder builder) {
+
+        return builder
+                .dataSource(userDataSource())
+                .packages("com.baeldung.entity")
+                .persistenceUnit("userPU")
+                .properties(Map.of("hibernate.hbm2ddl.auto", "none"))
+                .build();
+    }
+
+    @Bean
+    @Primary
+    public PlatformTransactionManager userTransactionManager(
+            EntityManagerFactory userEntityManagerFactory) {
+
+        return new JpaTransactionManager(userEntityManagerFactory);
+    }
+
+    @PostConstruct
+    public void migrateUserDb() {
+        Flyway.configure()
+                .dataSource(userDataSource())
+                .locations("classpath:db/migration/userdb")
+                .load()
+                .migrate();
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/entity/Product.java

@@ -0,0 +1,30 @@
+package com.baeldung.entity;
+
+import jakarta.persistence.*;
+
+@Entity
+@Table(name = "products")
+public class Product {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "product_seq")
+    private Long id;
+
+    private String name;
+
+    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;
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/entity/User.java

@@ -0,0 +1,31 @@
+package com.baeldung.entity;
+
+import jakarta.persistence.*;
+
+@Entity
+@Table(name = "users")
+public class User {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    private String name;
+
+
+    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;
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/repository/product/ProductRepository.java

@@ -0,0 +1,7 @@
+package com.baeldung.repository.product;
+
+import com.baeldung.entity.Product;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface ProductRepository extends JpaRepository<Product, Long> {
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/repository/user/UserRepository.java

@@ -0,0 +1,7 @@
+package com.baeldung.repository.user;
+
+import com.baeldung.entity.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface UserRepository extends JpaRepository<User, Long> {
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/service/ProductService.java

@@ -0,0 +1,27 @@
+package com.baeldung.service;
+
+import com.baeldung.entity.Product;
+import com.baeldung.repository.product.ProductRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.Optional;
+
+@Service
+public class ProductService {
+
+    private final ProductRepository repo;
+
+    public ProductService(ProductRepository repo) {
+        this.repo = repo;
+    }
+
+    @Transactional("productTransactionManager")
+    public Product save(Product product) {
+        return repo.save(product);
+    }
+
+    public Optional<Product> findById(Long id) {
+        return repo.findById(id);
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/java/com/baeldung/service/UserService.java

@@ -0,0 +1,27 @@
+package com.baeldung.service;
+
+import com.baeldung.entity.User;
+import com.baeldung.repository.user.UserRepository;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.Optional;
+
+@Service
+public class UserService {
+
+    private final UserRepository repo;
+
+    public UserService(UserRepository repo) {
+        this.repo = repo;
+    }
+
+    @Transactional("userTransactionManager")
+    public User save(User user) {
+        return repo.save(user);
+    }
+
+    public Optional<User> findById(Long id) {
+        return repo.findById(id);
+    }
+}

spring-boot-modules/flyway-multidb-springboot/src/main/resources/application.yml

@@ -0,0 +1,27 @@
+spring:
+  datasource:
+    userdb:
+      url: jdbc:h2:mem:userdb
+      username: sa
+      password:
+      driver-class-name: org.h2.Driver
+    productdb:
+      url: jdbc:h2:mem:productdb
+      username: sa
+      password:
+      driver-class-name: org.h2.Driver
+    application:
+      name: flyway-multidb-springboot
+
+  flyway:
+    enabled: false
+  jpa:
+    defer-datasource-initialization: false
+    hibernate:
+      ddl-auto: none
+  main:
+    allow-circular-references: true
+  h2:
+    console:
+      enabled: true
+      path: /h2-console

spring-boot-modules/flyway-multidb-springboot/src/main/resources/db.migration/productdb/V1__create_products_table.sql

@@ -0,0 +1,4 @@
+CREATE TABLE products (
+                          id BIGINT AUTO_INCREMENT PRIMARY KEY,
+                          name VARCHAR(255)
+);

spring-boot-modules/flyway-multidb-springboot/src/main/resources/db.migration/userdb/V1__create_users_table.sql

@@ -0,0 +1,4 @@
+CREATE TABLE users (
+                          id BIGINT PRIMARY KEY,
+                          name VARCHAR(255)
+);

spring-boot-modules/flyway-multidb-springboot/src/test/java/com/baeldung/flyway_multidb/FlywayMultidbApplicationTests.java

@@ -0,0 +1,13 @@
+package com.baeldung;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class FlywayMultidbApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}