Hikaricp configuration for multiple datasources - spring

Question

I have a multi database application. Users can select the database on the login page.
Then the database is routing selected database thanks for AbstractRoutingDataSource from Spring.
I want to use HikariCP, but it needs dataSourceUrl. But my Datasource URL changes dynamically. How can I configure Hikaricp for multiple databases?
File application.properties:
#database1 properties
app.database1.connection.url = url1
app.database1.connection.username = sameusername
app.database1.connection.password = samepassword
#database2 properties
app.database2.connection.url = url2
app.database2.connection.username = sameusername
app.database2.connection.password = samepassword
My Datasource configuration class example:
public class DataSourceConfiguration {
#Autowired(required = false)
private PersistenceUnitManager persistenceUnitManager;
#Bean
#ConfigurationProperties(prefix = "app.database1.connection")
public DataSource database1DataSource() {
return DataSourceBuilder.create().build();
}
#Bean
#ConfigurationProperties(prefix = "app.database2.connection")
public DataSource database2DataSource() {
return DataSourceBuilder.create().build();
}
#Bean
#Primary
public DataSource appDataSource() {
DataSourceRouter router = new DataSourceRouter();
final HashMap<Object, Object> map = new HashMap<>(3);
map.put(DatabaseEnvironment.DATABASE1, database1DataSource());
map.put(DatabaseEnvironment.DATABASE2, database2DataSource());
router.setTargetDataSources(map);
return router;
}
#Bean
#Primary
#ConfigurationProperties("app.connection.jpa")
public JpaProperties appJpaProperties() {
return new JpaProperties();
}
private JpaVendorAdapter createJpaVendorAdapter(JpaProperties jpaProperties) {
AbstractJpaVendorAdapter adapter = new HibernateJpaVendorAdapter();
adapter.setShowSql(jpaProperties.isShowSql());
adapter.setDatabase(jpaProperties.getDatabase());
adapter.setDatabasePlatform(jpaProperties.getDatabasePlatform());
adapter.setGenerateDdl(jpaProperties.isGenerateDdl());
return adapter;
}
My session scoped class instead of context holder:
#Component
#Scope(value = "session", proxyMode = ScopedProxyMode.TARGET_CLASS)
public class PreferredDatabaseSession implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private DatabaseEnvironment preferredDb;
public DatabaseEnvironment getPreferredDb() {
return preferredDb;
}
public void setPreferredDb(DatabaseEnvironment preferredDb) {
this.preferredDb = preferredDb;
}
}

Answer 1

If I understand your requirement correctly, you intend to define two data sources and for a given request you want to route your queries to a particular data source based on some condition.
The solution is:
File application.properties
#database1 properties
app.database1.connection.url = url1
app.database1.connection.username = username1
app.database1.connection.password = password1
#database2 properties
app.database2.connection.url = url2
app.database2.connection.username = username2
app.database2.connection.password = password2
#default
default.datasource.key=dataSource1
File CommonRoutingDataSource.java
public class CommonRoutingDataSource extends AbstractRoutingDataSource {
#Override
protected Object determineCurrentLookupKey() {
return DataSourceContextHolder.getDataSourceName();
}
public void initDataSources(final DataSource dataSource1, final DataSource dataSource2,
final String defaultDataSourceKey) {
final Map<Object, Object> dataSourceMap = new HashMap<Object, Object>();
dataSourceMap.put("dataSource1", dataSource1);
dataSourceMap.put("dataSource2", dataSource2);
this.setDefaultTargetDataSource(dataSourceMap.get(defaultDataSourceKey));
this.setTargetDataSources(dataSourceMap);
}
}
File DataSourceContextHolder.java
public class DataSourceContextHolder {
private static final ThreadLocal<String> contextHolder = new ThreadLocal<>();
private DataSourceContextHolder() {
// Private no-op constructor
}
public static final void setDataSourceName(final String dataSourceName) {
Assert.notNull(dataSourceName, "dataSourceName cannot be null");
contextHolder.set(dataSourceName);
}
public static final String getDataSourceName() {
return contextHolder.get();
}
public static final void clearDataSourceName() {
contextHolder.remove();
}
}
File DataSourceConfig.java
public class DataSourceConfig {
#Autowired
private Environment env;
#Autowired
#Bean(name = "dataSource")
public DataSource getDataSource(final DataSource dataSource1, final DataSource dataSource2) {
final CommonRoutingDataSource dataSource = new CommonRoutingDataSource();
dataSource.initDataSources(dataSource1, dataSource2, env.getProperty("default.datasource.key"));
return dataSource;
}
#Bean(name = "dataSource1")
public DataSource getDataSource1() throws SQLException {
// The exact DataSource class imported shall be as per your requirement - HikariCP, or Tomcat etc.
final DataSource dataSource = new DataSource();
dataSource.setDriverClassName();
dataSource.setUrl(env.getProperty("app.database1.connection.url"));
// Set all data source attributes from the application.properties file
return dataSource;
}
#Bean(name = "dataSource2")
public DataSource getDataSource2() throws SQLException {
// The exact DataSource class imported shall be as per your requirement - HikariCP, or Tomcat etc.
final DataSource dataSource = new DataSource();
dataSource.setDriverClassName();
dataSource.setUrl(env.getProperty("app.database2.connection.url"));
// set all data source attributes from the application.properties file
return dataSource;
}
}
Now, somewhere in your code (either an Aspect or Controller), you need to dynamically set the data source conditionally:
DataSourceContextHolder.setDataSourceName("dataSource1");
Note: It's better to declare the data source names as enums rather than strings "dataSource1", "dataSource2", etc.

Answer 2

The below snippet works for me
first.datasource.jdbc-url=jdbc-url
first.datasource.username=username
first.datasource.password=password
.
.
.
.
=================== In Java Configuration File ==================
#Primary
#Bean(name = "firstDataSource")
#ConfigurationProperties(prefix = "first.datasource")
public DataSource dataSource() {
return DataSourceBuilder.create().build();
}
#Primary
#Bean(name = "firstEntityManagerFactory")
public LocalContainerEntityManagerFactoryBean barEntityManagerFactory(EntityManagerFactoryBuilder builder,
#Qualifier("firstDataSource") DataSource dataSource) {
Map<String, String> props = new HashMap<String, String>();
props.put("spring.jpa.database-platform", "org.hibernate.dialect.Oracle12cDialect");
.
.
.
return builder.dataSource(dataSource).packages("com.first.entity").persistenceUnit("firstDB")
.properties(props)
.build();
}
#Primary
#Bean(name = "firstTransactionManager")
public PlatformTransactionManager firstTransactionManager(
#Qualifier("firstEntityManagerFactory") EntityManagerFactory firstEntityManagerFactory) {
return new JpaTransactionManager(firstEntityManagerFactory);
}
second.datasource.jdbc-url=jdbc-url
second.datasource.username=username
second.datasource.password=password
.
.
.
.
=================== In Java Configuration File ==================
#Bean(name = "secondDataSource")
#ConfigurationProperties(prefix = "second.datasource")
public DataSource dataSource() {
return DataSourceBuilder.create().build();
}
#Bean(name = "secondEntityManagerFactory")
public LocalContainerEntityManagerFactoryBean barEntityManagerFactory(EntityManagerFactoryBuilder builder,
#Qualifier("secondDataSource") DataSource dataSource) {
Map<String, String> props = new HashMap<String, String>();
props.put("spring.jpa.database-platform", "org.hibernate.dialect.Oracle12cDialect");
.
.
.
return builder.dataSource(dataSource).packages("com.second.entity").persistenceUnit("secondDB")
.properties(props)
.build();
}
#Bean(name = "secondTransactionManager")
public PlatformTransactionManager secondTransactionManager(
#Qualifier("secondEntityManagerFactory") EntityManagerFactory secondEntityManagerFactory) {
return new JpaTransactionManager(secondEntityManagerFactory);
}