I am developing a spring boot project where i am having two functions for JPA on which i need to figure out which function will perform better and put less pressure on database query performance and utilise Hibernate caching. Please guide on which query to use.
My Repository interface:
#Repository
public interface CustomersRepository
extends JpaRepository<CustomersEntity, Long> {
#Query(nativeQuery = true, value = "SELECT * FROM customers WHERE c_mobile = ?1")
CustomersEntity findcustomerByMobile(String mobileNo);
#Override
List<CustomersEntity> findAll();
}
My Service class:
#Scope("request")
#Service
public class CustomerServiceImpl implements ICustomerService {
#Autowired
private CustomersRepository customersRepository;
#Override
public boolean findCustomerByMobile1(long mobileNo) {
CustomersEntity customersEntity = customersRepository.findcustomerByMobile(mobileNo);
if (customersEntity != null)
return true;
else
return false;
}
#Override
public boolean findCustomerByMobile2(long mobileNo) {
List<CustomersEntity> entityList = customersRepository.findAll();
for (CustomersEntity entity : entityList) {
if (entity.getcMobile() == mobileNo) {
return true;
}
}
return false;
}
}
There is no need to download all records from the database to your app and then filtering them. With thousands of records it will slow down.
Instead you should create an index on c_mobile field then use just like this simple method:
public interface CustomerRepo extends JpaRepository<CustomersEntity, Long> {
CustomersEntity findByMobileNo(String mobileNo);
}
It will work in a flash (with index).
More info about building query methods you can find here.
Related
I´m currently trying to implement multi-tenancy into my JHipster microservices. However, I can't find a way to implement tenant-based routing for elasticsearch.
So far I have managed to implement datasource routing for the PostgreSQL DBs similar to the following article: https://websparrow.org/spring/spring-boot-dynamic-datasource-routing-using-abstractroutingdatasource
When I started looking for ways to implement multi tenancy in elasticsearch, I found the following article: https://techblog.bozho.net/elasticsearch-multitenancy-with-routing/
There I read about tenant-based routing. First I tried looking it up on the internet, but anything I found was either over 5 years old or not related to java, much less to Spring/Jhipster. Then I tried looking into the methods of ElasticSearchTemplate, the annotation variables of #Document and #Settings and the configuration options in the .yml file, but didn't find anything useful.
I'm currently using Jhipster version 7.9.3, which uses the Spring-Boot version 2.7.3. All the microservices were created with JDL and on half of them I put elasticsearch into the configuration. The other half does not matter.
Edit: I want to add that multi-tenancy in my database is archived by database separation(Tenant1 uses DB1, Tenant2 uses DB2 etc.). The tenant variable is an enum and not included in my entities.
Edit2: I implemented my own solution. I use the tenants as indexes and use my ContextHolder from DataSource Routing to route to the correct tenant index. For that I had to do some changes the elasticsearchTemplate in the generated classes of the package "<my.package.name>.repository.search".
It might not be the most efficient way to reach multi tenancy with elasticsearch, but it doesn't need much configuration.
Here is the code:
public interface ProductSearchRepository extends ElasticsearchRepository<Product, Long>, ProductSearchRepositoryInternal {}
interface ProductSearchRepositoryInternal {
Stream<Product> search(String query);
Stream<Product> search(Query query);
void index(Product entity);
}
class ProductSearchRepositoryInternalImpl implements ProductSearchRepositoryInternal {
private final ElasticsearchRestTemplate elasticsearchTemplate;
private final ProductRepository repository;
ProductSearchRepositoryInternalImpl(ElasticsearchRestTemplate elasticsearchTemplate, ProductRepository repository) {
this.elasticsearchTemplate = elasticsearchTemplate;
this.repository = repository;
}
#Override
public Stream<Product> search(String query) {
NativeSearchQuery nativeSearchQuery = new NativeSearchQuery(queryStringQuery(query));
return search(nativeSearchQuery);
}
#Override
public Stream<Product> search(Query query) {
return elasticsearchTemplate.search(query, Product.class, IndexCoordinates.of(TenantContextHolder.getTenantContext().getTenant())).map(SearchHit::getContent).stream();
}
#Override
public void index(Product entity) {
repository.findById(entity.getId()).ifPresent(t -> elasticsearchTemplate.save(t, IndexCoordinates.of(TenantContextHolder.getTenantContext().getTenant())));
}
}
Edit3: Since people might not know where ".getTenant()" comes from, I'll show my tenant enumeration:
public enum Tenant {
TENANTA("tenant_a"),
TENANTB("tenant_b");
String tenant;
Tenant(String name) {
this.tenant=name;
}
public String getTenant() {
return this.tenant;
}
}
Edit4: My solution is not working as planned. I will give an update once I found a better and more robust solution.
Edit5: I have found out how to implement tenant-based routing. First you have to add the following Annotation to your entities:
#org.springframework.data.elasticsearch.annotations.Routing(value = "tenant")
In my case I had to include the enum "Tenant" into my entities along with the getter and setter:
#Transient
private Tenant tenant;
public Tenant getTenant() {
return tenant;
}
public void setTenant(Tenant tenant) {
this.tenant = tenant;
}
Then I have to set the tenant during the processing of a REST request before it gets indexed by elasticsearchtemplate:
entity.setTenant(TenantContextHolder.getTenantContext());
As for the search function, I had to add a term query as a filter to enable routing:
#Override
public Stream<Product> search(String query) {
NativeSearchQuery nativeSearchQuery = new NativeSearchQuery(queryStringQuery(query)
, QueryBuilders.termQuery("_routing", TenantContextHolder.getTenantContext()));
return search(nativeSearchQuery);
}
The method "setRoute(String route)" of "nativeSearchQuery" either does not work in my case or I didn't understand how it works.
I have successfully tested this implementation with GET and POST requests. Currently I have a problem with elasticsearch overwriting data if the id of the entity from one tenant I want to save is the same id as another entity with a different tenant.
After some trial and error, I found a solution to the overwriting problem and successfully completed and tested my implementation of tenant-based routing. Here is the code:
Product.java
import java.io.Serializable;
import javax.persistence.*;
import org.hibernate.annotations.Cache;
import org.hibernate.annotations.CacheConcurrencyStrategy;
import org.springframework.data.elasticsearch.annotations.Field;
#Entity
#Table(name = "product")
#Cache(usage = CacheConcurrencyStrategy.READ_WRITE)
#org.springframework.data.elasticsearch.annotations.Document(indexName = "product")
#SuppressWarnings("common-java:DuplicatedBlocks")
#org.springframework.data.elasticsearch.annotations.Routing(value = "tenant")
public class Product implements Serializable {
private static final long serialVersionUID = 1L;
#Transient
private Tenant tenant;
#Transient
#Field(name = "elastic_id")
#org.springframework.data.annotation.Id
private String elasticsearchId;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator =
"sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator")
#Column(name = "id")
#Field("postgres_id")
private Long id;
//Getters, Setters and other variables
}
ProductSearchRepository
public interface ProductSearchRepository extends ElasticsearchRepository<Product, Long>, ProductSearchRepositoryInternal {}
interface ProductSearchRepositoryInternal {
Stream<Product> search(String query);
Stream<Product> search(Query query);
void index(Product entity);
Product save(Product entity);
void deleteById(Long id);
}
#Transactional
class ProductSearchRepositoryInternalImpl implements ProductSearchRepositoryInternal {
private final ElasticsearchRestTemplate elasticsearchTemplate;
private final ProductRepository repository;
ProductSearchRepositoryInternalImpl(ElasticsearchRestTemplate elasticsearchTemplate, ProductRepository repository) {
this.elasticsearchTemplate = elasticsearchTemplate;
this.repository = repository;
}
#Override
public Stream<Product> search(String query) {
NativeSearchQuery nativeSearchQuery = new NativeSearchQuery(queryStringQuery(query)
, QueryBuilders.termQuery("_routing", TenantContextHolder.getTenantContext()));
nativeSearchQuery.setMaxResults(30);
return search(nativeSearchQuery);
}
#Override
public Stream<Product> search(Query query) {
return elasticsearchTemplate.search(query, Product.class).map(SearchHit::getContent).stream();
}
#Override
public void index(Product entity) {
entity.setTenant(TenantContextHolder.getTenantContext());
repository.findById(Long.valueOf(entity.getId())).ifPresent(t -> {
entity.setElasticsearchId(entity.getTenant()+String.valueOf(entity.getId()));
elasticsearchTemplate.save(t);
});
}
#Override
public Product save(Product entity) {
entity.setTenant(TenantContextHolder.getTenantContext());
entity.setElasticsearchId(entity.getTenant()+String.valueOf(entity.getId()));
return elasticsearchTemplate.save(entity);
}
#Override
public void deleteById(Long id) {
elasticsearchTemplate.delete(TenantContextHolder.getTenantContext() + String.valueOf(id), Product.class);
}
}
Assuming I've the following endpoints in spring boot
GET /todo
DELETE /todo/{id}
How can ensure that only entries for the userid are returned and that the user can only update his own todos?
I've a populated Authentication object.
Is there any build in way I can use? Or just make sure to always call findXyzByIdAndUserId where userid is always retrieved from the Principal?
I'm a bit worried about the possibility to forget the check and displaying entries from other users.
My approach to this would be a 3 way implementation: (using jpa & hibernate)
a user request context
a mapped superclass to get your context
a statement inspector to inject your userid
For example:
public final class UserRequestContext {
public static String getUserId() {
// code to retrieve your userid and throw when there is none!
if (userId == null) throw new IllegalStateException("userid null");
return userId;
}
}
#MappedSuperclass
public class UserResolver {
public static final String USER_RESOLVER = "USER_RESOLVER";
#Access(AccessType.PROPERTY)
public String getUserId() {
return UserRequestContext.getUserId();
}
}
#Component
public class UserInspector implements StatementInspector {
#Override
public String inspect(String statement) {
if (statement.contains(UserResolver.USER_RESOLVER)) {
statement = statement.replace(UserResolver.USER_RESOLVER, "userId = '" + UserRequestContext.getUserId() + "'" );
}
return sql;
}
#Bean
public HibernatePropertyCustomizer hibernatePropertyCustomizer() {
return hibernateProperies -> hibernateProperties.put("hibernate.session_factory.statement_inspector",
UserInspector.class.getName());
}
}
So your Entity looks like this:
#Entity
...
#Where(clause = UserResolver.USER_RESOLVER)
public class Todo extends UserResolver {
...
}
Trying to mix PagingAndSortingRepository with custom queries, no luck..
Custom repo:
public interface SiteRepositoryCustom
{
public List<SitesDbRecord> getActiveSites();
}
Impl repo:
#Repository
public class SiteRepositoryImpl implements SiteRepositoryCustom
{
private static final Logger logger = ...
#PersistenceContext
private EntityManager em;
#Override
public List<SitesDbRecord> getActiveSites()
{
logger.info( "getActiveSites start" );
try
{
String hql = "select s from SitesDbRecord s where s.isActive = true";
return em.createQuery( hql ).setMaxResults( Integer.MAX_VALUE ).getResultList();
}
catch ( Exception e )
{
logger.error( "getActiveSites failed.", e );
return null;
}
}
}
The repo injected to the service:
public interface SiteRepository extends PagingAndSortingRepository<SitesDbRecord, Integer>, SiteRepositoryCustom {
public List<SitesDbRecord> getActiveSites( Pageable pageable );
public List<SitesDbRecord> getActiveSites();
}
If I just extend CrudRepository (without the Pageable method) then all is OK. Trying to extend PagingAndSortingRepository (with or without the Pageable method) then Spring fails to boot with
PropertyReferenceException: No property getActiveSites found for type SitesDbRecord!
What is the correct way to use PagingAndSortingRepository with custom queries? Probably got it wrong, but I assumed it's Spring responsibility to provide the handling of paging/sorting.
If SitesDbRecord has boolean property named active it should be:
public interface SiteRepository extends PagingAndSortingRepository<SitesDbRecord, Integer> {
public List<SitesDbRecord> findByActiveIsTrue( Pageable pageable );
public List<SitesDbRecord> findByActiveIsTrue();
}
There is no need to extend your Custom repository, just implement PagingAndSortingRepository
The Service class and my repository classes in my spring MVC set up are something like this -
public class ObjectServiceImpl implements ObjectService {
#Autowired
Temp1Repo temp1Repo;
#Autowired
Temp2Repo temp2Repo;
...
}
public interface Temp1Repo extends CrudRepository<Temp1, Integer> {
}
public interface Temp2Repo extends CrudRepository<Temp2, Integer> {
}
Now, in my service class, i am getting a object of a type Temp1, I have to call temp1Repo.save(). If I get an object of Temp2, I have to call temp2Repo.save() and so on...
How do i achieve this?
Seems fairly simple to just have an if statement:
if(object instanceof Temp1) {
temp1Repo.save((Temp1) object);
} else if(object instanceof Temp2) {
temp2Repo.save((Temp2) object);
}
Or perhaps you are looking for a more generic way?
I suppose that you want to regroup all repositories in one. Something like
#SuppressWarnings("rawtypes")
public class ObjectServiceImpl {
#Autowired
private CrudRepository[] repositories;
private Map<Class<?>, CrudRepository> repositoryMap = new HashMap<Class<?>, CrudRepository>();
#PostConstruct
public void init() {
for (CrudRepository r : repositories)
repositoryMap.put(getType(r), r);
}
private Class<?> getType(CrudRepository repository) {
Type[] types = repository.getClass().getGenericInterfaces();
for (Type t : types) {
if (t instanceof ParameterizedType)
return (Class<?>) ((ParameterizedType) t).getActualTypeArguments()[0];
}
throw new IllegalStateException("Check repositories...");
}
public void save(Object entity) {
repositoryMap.get(entity.getClass()).save(entity);
}
public <T> T get(Object id, Class<T> clazz) {
return repositoryMap.get(clazz).findOne(id);
}
....
}
Consider to use EntityManager directly, but could be useful anyway...
Following the code you wrote, Spring will rise an exception at startup time if any injection is missing.
What you want to do is a dynamic Module load, depending on a condition you omitted within your question.
You probably have to use XML configuration style and create a by condition spring context and load the correct one to be used.
Cheers
I'm using spring mvc and I created the CRUD functionality. But I want to create a search function that will allow me to find a user by any parameter (variable) as 'userid' or 'username' or 'lastname' or 'social security number' or whatever.
My userid is an integer type.
How can I do that? What is the SQL query for that?
How can I check if the input is integer or string and then go through the database by the given parameter and search for the user?
If you are using Hibernate for data access you can easily create universal finder using criteria API:
Abstract DAO class:
public abstract class AbstractHibernateDAO<T> {
private static final String PARAM_VALUE_PARAMETER = "paramValue";
private final Class<T> clazz;
#Autowired
private SessionFactory sessionFactory;
public AbstractHibernateDAO(Class<T> clazz) {
this.clazz = clazz;
}
public T findOne(String paramName, Object paramValue) {
Session session = sessionFactory.getCurrentSession();
#SuppressWarnings("unchecked")
T fetchedObject = (T) session.createCriteria(clazz).add(Restrictions.eq(paramName, paramValue)).uniqueResult();
return fetchedObject;
}
// Other CRUD methods.
}
Concrete DAO class for entity:
#Repository
#Transactional
public class ProductHibernateDAO extends AbstractHibernateDAO<Product> {
public ProductHibernateDAO() {
super(Product.class);
}
}
Or if you prefer to use HQL instead of Criteria API you can rewrite search method as:
public T findOne(String paramName, Object paramValue) {
Session session = sessionFactory.getCurrentSession();
StringBuilder queryText = new StringBuilder();
queryText.append("from ");
queryText.append(clazz.getSimpleName());
queryText.append(" where ");
queryText.append(paramName);
queryText.append("=:");
queryText.append(PARAM_VALUE_PARAMETER);
#SuppressWarnings("unchecked")
T fetchedObject = (T) session.createQuery(queryText.toString()).setParameter(PARAM_VALUE_PARAMETER, paramValue).uniqueResult();
return fetchedObject;
}
In this article you can find very good description how to create generic DAO with hibernate (Or if you prefer JPA there are also described how to do this with JPA).
Or if you prefer to use JDBC for data access I recommend you to look at Spring's JdbcTemplate. It simplifies development a lot. Here how you can implement universal finder using JdbcTemplate:
#Repository
#Transactional
public class ProductJDBCDAO implements DAO<Product> {
private static final String TABLE_NAME = "product";
#Autowired
private JdbcTemplate jdbcTemplate;
public Product findOne(String paramName, Object paramValue) {
RowMapper<Product> rowMapper = new RowMapper<Product>(){
public Product mapRow(ResultSet rs, int rowNum) throws SQLException {
long productId = rs.getLong("product_id");
// Other properties
Product product = new Product(...);
return product;
}
};
StringBuilder queryText = new StringBuilder();
queryText.append("select * from ");
queryText.append(TABLE_NAME);
queryText.append(" where ");
queryText.append(paramName);
queryText.append("=?");
Product fetchedObject = jdbcTemplate.queryForObject(queryText.toString(), rowMapper, paramValue);
return fetchedObject;
}
// Other CRUD methods
}
Ass you can see in all examples you don't need explicitly specify parameter type, you just add it as Object parameter.
If you will work with direct JDBC in such case I recommend you to use PreparedStatement and it's setObject(..) method. Query text will be similar to shown in the example with JdbcTemplate.