Spring Cloud AWS – RDS

1. RDS Support

1.1. Simple Configuration

Spring Cloud AWS can automatically create a DataSource just by specifying the RDS database identifier and the master password. The username, JDBC driver, and the complete URL are all resolved by Spring.

If an AWS account has an RDS instance with DB instance identifier as spring-cloud-test-db having master password se3retpass, then all that’s required to create a DataSource is the following line in application.properties:

cloud.aws.rds.spring-cloud-test-db.password=se3retpass

Three other properties can be added if you wish to use values other than the RDS default:

cloud.aws.rds.spring-cloud-test-db.username=testuser
cloud.aws.rds.spring-cloud-test-db.readReplicaSupport=true
cloud.aws.rds.spring-cloud-test-db.databaseName=test

1.2. Custom Datasource

In an application without Spring Boot or in cases where custom configurations are required, we can also create the DataSource using the Java-based configuration:

@Configuration
@EnableRdsInstance(
  dbInstanceIdentifier = "spring-cloud-test-db", 
  password = "se3retpass")
public class SpringRDSSupport {

    @Bean
    public RdsInstanceConfigurer instanceConfigurer() {
        return () -> {
            TomcatJdbcDataSourceFactory dataSourceFactory
             = new TomcatJdbcDataSourceFactory();
            dataSourceFactory.setInitialSize(10);
            dataSourceFactory.setValidationQuery("SELECT 1");
            return dataSourceFactory;
        };
    }
}

Also, note that we need to add the correct JDBC driver dependency.

2. Conclusion

In this article, we had a look at various ways of accessing AWS RDS service; in the next and final article of the series, we’ll have a look at AWS Messaging support.

As usual, the examples are available over on GitHub.