Spring Boot - Same repository and same entity for different databases - spring

Question

I have a Spring Boot project with one entity and one repository associated to this entity. In the repository there is one method with a custom query and in the project controller this repository is used to return data from different postgresql databases. These databases have same tables with same columns (so the referred entity is the same), the only difference among these databases is the year (..., DB2015, DB2016, DB2017).
My questions are: How can i return data in the project controller that belong to "different" databases? Is possible to use the same query to select data initially from the first database, then from the second and so on?
In other questions i've read that i need different datasources, is this correct?
This is the entity:
#Entity(name = "REQUEST")
public class Request implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
#Id
#Column(name="IDREQUEST", nullable=false)
private BigDecimal idrequest;
#Column(name="PAYLOAD")
private String payload;
#Column(name="MITTENTE")
private String mittente;
#Column(name="SERVIZIO")
private String servizio;
#Column(name="DATARICEZIONE")
private BigDecimal dataricezione;
public BigDecimal getIdrequest() {
return idrequest;
}
public void setIdrequest(BigDecimal idrequest) {
this.idrequest = idrequest;
}
public String getPayload() {
return payload;
}
public void setPayload(String payload) {
this.payload = payload;
}
public String getMittente() {
return mittente;
}
public void setMittente(String mittente) {
this.mittente = mittente;
}
public String getServizio() {
return servizio;
}
public void setServizio(String servizio) {
this.servizio = servizio;
}
public BigDecimal getDataricezione() {
return dataricezione;
}
public void setDataricezione(BigDecimal dataricezione) {
this.dataricezione = dataricezione;
}
}
This is the repository:
#Repository
public interface RequestRepository extends PagingAndSortingRepository<Request, BigDecimal> {
#Query(nativeQuery=true, value="SELECT * FROM \"REQUEST\" WHERE strpos(\"PAYLOAD\",\'?1\') > 0")
List<Request> findByCodiceFiscale(String codiceFiscale);
}
This is the controller
#RequestMapping(value="/ricercaadesioni/{codicefiscale}", method=RequestMethod.GET)
public ResponseEntity<List<Request>> ricercaAdesioniByCodiceFIscale(#PathVariable("codicefiscale") String codicefiscale) {
List<Request> listAdesioni = requestRepo.findByCodiceFiscale(codicefiscale);
return new ResponseEntity<List<Request>>(listAdesioni, HttpStatus.OK);
}
This is application.properties (in this case the datasource is referred to one db only):
spring.datasource.url=jdbc:postgresql://localhost:5432/DB2017_test
spring.datasource.username=xxx
spring.datasource.password=xxx
Hope everything is clear

Answer 1

Create 2 config files with different datasource and these 2 config files will have different specifications for 2 different jpa repository class.but can have same domain class.
step1>
In your properties file have 2 datasource details.
spring.datasource.url=jdbc:postgresql://localhost:5432/DB2017_test
spring.datasource.username=xxx
spring.datasource.password=xxx
# DB2018 DB - ""
spring.datasource2.url=jdbc:postgresql://localhost:5432/DB2018_test
spring.datasource2.username=xxx
spring.datasource2.password=xxx
step2>Then create config file for first dataSource
package com.package1;
#Configuration
#EnableTransactionManagement
#EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactory",
basePackages = { "com.package1.repo" }
)
public class DB2017Config {
#Primary
#Bean(name = "dataSource")
#ConfigurationProperties(prefix = "spring.datasource")
public DataSource dataSource() {
return DataSourceBuilder.create().build();
}
#Primary
#Bean(name = "entityManagerFactory")
public LocalContainerEntityManagerFactoryBean
entityManagerFactory(
EntityManagerFactoryBuilder builder,
#Qualifier("dataSource") DataSource dataSource
) {
return builder
.dataSource(dataSource)
.packages("com.domain")
.persistenceUnit("foo")
.build();
}
#Primary
#Bean(name = "transactionManager")
public PlatformTransactionManager transactionManager(
#Qualifier("entityManagerFactory") EntityManagerFactory
entityManagerFactory
) {
return new JpaTransactionManager(entityManagerFactory);
}
}
step3> Similary create another config file for other dataSource,
#EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactory",
basePackages = { "com.package2.repo" }
And change prefix
#ConfigurationProperties(prefix = "spring.datasource2")
Now you will have 2 similar RequestRepository1 and RequestRepository2 in package1 and package2 respectiverly as mentioned above (basePackages = { "com.package1.repo" }).
step4>All set autowire 2 different repo .
#Autowired
private final RequestRepository1 repo1;
#Autowired
private final RequestRepository2 repo2;
Then use them.
List<Request> listAdesioni = repo1.findByCodiceFiscale(codicefiscale);
List<Request> listAdesioni = repo2.findByCodiceFiscale(codicefiscale);