Spring boot - Issue with multiple DataSource - spring

Question

I have a ReST service that needs to fetch data from two different DBs (Oracle and MySQL) and merge this data in the response.
I have below configuration.
Config for DB 1:
#Configuration
public class DbConfig_DB1{
#Bean(name="siebelDataSource")
public EmbeddedDatabase siebelDataSource(){
return new EmbeddedDatabaseBuilder().
setType(EmbeddedDatabaseType.H2).
addScript("schema.sql").
addScript("test-data.sql").
build();
}
#Autowired
#Qualifier("siebelDataSource")
#Bean(name = "siebelJdbcTemplate")
public JdbcTemplate siebelJdbcTemplate(DataSource siebelDataSource) {
return new JdbcTemplate(siebelDataSource);
}
}
Config for DB2:
#Configuration
public class DbConfig_DB2{
#Bean(name="brmDataSource")
public EmbeddedDatabase brmDataSource(){
return new EmbeddedDatabaseBuilder().
setType(EmbeddedDatabaseType.H2).
addScript("schema-1.sql").
addScript("test-data-1.sql").
build();
}
#Autowired
#Qualifier("brmDataSource")
#Bean(name = "brmJdbcTemplate")
public JdbcTemplate brmJdbcTemplate(DataSource brmDataSource) {
return new JdbcTemplate(brmDataSource);
}
}
Data Access:
#Repository
public class SiebelDataAccess {
protected final Logger log = LoggerFactory.getLogger(getClass());
#Autowired
#Qualifier("siebelJdbcTemplate")
protected JdbcTemplate jdbc;
public String getEmpName(Integer id) {
System.out.println(jdbc.queryForObject("select count(*) from employee", Integer.class));
Object[] parameters = new Object[] { id };
String name = jdbc.queryForObject(
"select name from employee where id = ?", parameters,
String.class);
return name;
}
}
I am not able to start the app as I below error:
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private javax.sql.DataSource org.springframework.boot.autoconfigure.jdbc.DataSourceTransactionManagerAutoConfiguration.dataSource;
nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.sql.DataSource] is defined: expected single matching bean but found 2: brmDataSource,siebelDataSource
The issue is with two DataSource beans in the context. How to resolve this?

Answer 1

You could mark one of them as #Primary so Spring Boot auto configuration for transactions manager would know which one to pick. If you need to manage transactions with both of them then I'm afraid you would have to setup transactions management explicitly.
Please refer to the Spring Boot documentation
Creating more than one data source works the same as creating the first one. You might want to mark one of them as #Primary if you are using the default auto-configuration for JDBC or JPA (then that one will be picked up by any #Autowired injections).