Multiple DataSources across 2 components-CodePudding

I have 2 Spring Boot applications App1 and App2. App2 can run as a standalone application and also is embedded in application App1 as a dependency. I want App1 to be able to make calls to services of App2 which makes repo calls to a different DB. I have configured DataSource beans in both components as follows:

App1

  @Configuration
  @EnableJpaRepositories(basePackages = "com.ev.app1.repositories",
  entityManagerFactoryRef = "app1EntityManagerFactory",
  transactionManagerRef = "app1TransactionManager")
  public class PersistenceApp1Configuration {
    @Bean
    @ConfigurationProperties(prefix = "app.datasource.app1")
    public DataSourceProperties app1DataSourceProperties() {
      return new DataSourceProperties();
    }

    @Bean(name = "app1DataSource")
    @ConfigurationProperties(prefix = "app.datasource.app1")
    public DataSource tmDataSource() {
      return tmDataSourceProperties().initializeDataSourceBuilder()
      .type(BasicDataSource.class).build();
    }

App1 application.properties:

app.datasource.app1.url=jdbc:postgresql://localhost:5432/mercury_tmdb?currentSchema=txm
app.datasource.app1.username=postgres
app.datasource.app1.password=root
app.datasource.app1.driverClassName=org.postgresql.Driver

App2

  @Configuration
  @EnableJpaRepositories(basePackages = "com.ev.app1.repositories",
  entityManagerFactoryRef = "app1EntityManagerFactory",
  transactionManagerRef = "app1TransactionManager")
  public class PersistenceApp1Configuration {
    @Bean
    @ConfigurationProperties(prefix = "app.datasource.app1")
    public DataSourceProperties app1DataSourceProperties() {
      return new DataSourceProperties();
    }

    @Bean(name = "app2DataSource")
    @Primary
    @ConfigurationProperties(prefix = "app.datasource.app2")
    public DataSource app2DataSource() {
    return tmDataSourceProperties().initializeDataSourceBuilder()
      .type(BasicDataSource.class).build();
    }

App2 application.properties:

app.datasource.app2.url=jdbc:postgresql://localhost:5432/mercury_cldb?currentSchema=led
app.datasource.app2.username=postgres
app.datasource.app2.password=root
app.datasource.app2.driverClassName=org.postgresql.Driver

As you can see, I had to mark the DataSource bean in App2 as @Primary to override the default spring datasource. But the same I cannot do for App1 since it already has a Primary bean from App2. Any work around for this? Or may be I am completely off with this approach?

Note: I have other config beans which I haven't shown here but I can share if required

CodePudding user response：

You can use the conditional bean configuration from Spring, so you can decide when to use each datasource.

You can use the annotation like this:

@ConditionalOnExpression(value = "${module.enabled} and ${module.submodule.enabled}")

depending on your specific configuration.