Configuring Spring transactions support for MongoDB - spring

I am using spring-boot-starter-data-mongodb:2.2.1.RELEASE and trying to add transaction support for Mongo DB operations.
I have the account service below, where documents are inserted into two collections accounts and profiles. In case an error occurs while inserting into profile collection, the insertion into accounts should rollback. I have configured Spring transactions using MongoTransactionManager.
#Service
public class AccountService {
#Transactional
public void register(UserAccount userAccount) {
userAccount = accountRepository.save(userAccount);
UserProfile userProfile = new UserProfile(userAccountDoc.getId());
userProfile = profileRepository.save(userProfile);
}
}
Enabled Spring transaction support for MongoDB.
#Configuration
public abstract class MongoConfig extends AbstractMongoConfiguration {
#Bean
MongoTransactionManager transactionManager(MongoDbFactory dbFactory) {
return new MongoTransactionManager(dbFactory);
}
}
As per Spring reference doc https://docs.spring.io/spring-data/mongodb/docs/2.2.1.RELEASE/reference/html/#mongo.transactions that is all required to enable transactions for MongoDB. But this is not working. Insertions into accounts collection are not rolled back in case error occurs while inserting into profiles collection. Any suggestions if I am missing anything?

I would use command monitoring or examine query logs on the server side to ensure that:
session ids are sent with queries/write commands
transaction operations are performed (there is no startTransaction command but there is a commitTransaction)

Related

Spring Data Mongo Db transactional annotation error handling of TransientTransactionError

I have multiple operations on Mongo which I want to be considered as one operation so I enabled transactions. I'm using Mongo version 5.
The configuration class contains the following bean definition:
#Bean(name = "transactionManager")
MongoTransactionManager transactionManager(MongoDatabaseFactory dbFactory) {
return new MongoTransactionManager(dbFactory);
}
My business logic is similar to below snippet. Assume inside this method there are changes done on different collections.
#Transactional
public MyResult create(String payload) {
//operations omitted for brevity
}
Based on the Mongo documentation (https://www.mongodb.com/docs/v5.0/core/transactions/) I quote:
The new callback API also incorporates retry logic for TransientTransactionError or UnknownTransactionCommitResult commit errors.
Also this as reference: https://github.com/mongodb/specifications/blob/master/source/transactions/transactions.rst#error-labels
Does Spring data Mongo db know how to handle the TransientTransactionError (including the retry described in the docs)? If not what are the alternatives?

Spring boot #Transactional doesn't rollback

I am using Spring boot application, on that i am trying to achieve Transactional management. But Spring doesn't rollback the data which saved in same method.
Code base: https://github.com/vinothr/spring-boot-transactional-example
Can any one help me?
This is my repository class for 'Test' entity.
#Repository
public interface TestRepository extends CrudRepository<com.example.demo.Test, Long> {
}
I have created one end-point which used to save the data to 'Test' entity. After save happen, I thrown RunTimeException, but it is not rollbacking the saved value
#GetMapping("/test")
#Transactional
public void create() {
System.out.println("test");
final Test p = createTest();
testRepository.save(p);
final Test p1 = createTest();
testRepository.save(p1);
throw new RuntimeException();
}
It works fine after I changed into 'InnoDB' engine because I was using 'MyISAM' engine which doesn't support transaction.
ALTER TABLE my_table ENGINE = InnoDB;
Try indicate #Transactional(rollbackFor = RuntimeException.class)

Why does OpenEntityManagerInViewFilter change #Transactional propagation REQUIRES_NEW behavior?

Using Spring 4.3.12, Spring Data JPA 1.11.8 and Hibernate 5.2.12.
We use the OpenEntityManagerInViewFilter to ensure our entity relationships do not throw LazyInitializationException after an entity has been loaded. Often in our controllers we use a #ModelAttribute annotated method to load an entity by id and make that loaded entity available to a controller's request mapping handler method.
In some cases like auditing we have entity modifications that we want to commit even when some other transaction may error and rollback. Therefore we annotate our audit work with #Transactional(propagation = Propagation.REQUIRES_NEW) to ensure this transaction will commit successfully regardless of any other (if any) transactions which may or may not complete successfully.
What I've seen in practice using the OpenEntityManagerInviewFilter, is that when Propagation.REQUIRES_NEW transactions attempt to commit changes which occurred outside the scope of the new transaction causing work which should always result in successful commits to the database to instead rollback.
Example
Given this Spring Data JPA powered repository (the EmployeeRepository is similarly defined):
import org.springframework.data.jpa.repository.JpaRepository;
public interface MethodAuditRepository extends JpaRepository<MethodAudit,Long> {
}
This service:
#Service
public class MethodAuditorImpl implements MethodAuditor {
private final MethodAuditRepository methodAuditRepository;
public MethodAuditorImpl(MethodAuditRepository methodAuditRepository) {
this.methodAuditRepository = methodAuditRepository;
}
#Override #Transactional(propagation = Propagation.REQUIRES_NEW)
public void auditMethod(String methodName) {
MethodAudit audit = new MethodAudit();
audit.setMethodName(methodName);
audit.setInvocationTime(LocalDateTime.now());
methodAuditRepository.save(audit);
}
}
And this controller:
#Controller
public class StackOverflowQuestionController {
private final EmployeeRepository employeeRepository;
private final MethodAuditor methodAuditor;
public StackOverflowQuestionController(EmployeeRepository employeeRepository, MethodAuditor methodAuditor) {
this.employeeRepository = employeeRepository;
this.methodAuditor = methodAuditor;
}
#ModelAttribute
public Employee loadEmployee(#RequestParam Long id) {
return employeeRepository.findOne(id);
}
#GetMapping("/updateEmployee")
// #Transactional // <-- When uncommented, transactions work as expected (using OpenEntityManagerInViewFilter or not)
public String updateEmployee(#ModelAttribute Employee employee, RedirectAttributes ra) {
// method auditor performs work in new transaction
methodAuditor.auditMethod("updateEmployee"); // <-- at close of this method, employee update occurrs trigging rollback
// No code after this point executes
System.out.println(employee.getPin());
employeeRepository.save(employee);
return "redirect:/";
}
}
When the updateEmployee method is exercised with an invalid pin number updateEmployee?id=1&pin=12345 (pin number is limited in the database to 4 characters), then no audit is inserted into the database.
Why is this? Shouldn't the current transaction be suspended when the MethodAuditor is invoked? Why is the modified employee flushing when this Propagation.REQUIRES_NEW transaction commits?
If I wrap the updateEmployee method in a transaction by annotating it as #Transactional, however, audits will persist as desired. And this will work as expected whether or not the OpenEntityManagerInViewFilter is used.
While your application (server) tries to make two separate transactions you are still using a single EntityManager and single Datasource so at any given time JPA and the database see just one transaction. So if you want those things to be separated you need to setup two Datasources and two EntityManagers

Spring AbstractRoutingDataSource is caching Datasource

I have a Spring MVC application deployed as Multi-Tenant (Single Instance) on Tomcat. All users login to the same application.
User belongs to a Region, and each Region has a separate Database instance.
We are using Dynamic DataSource Routing using Spring AbstractRoutingDataSource".
This works correctly only for the first time, when User_1 from Region_1 logs into the application, Datasource_1 is correctly assigned.
But subsequently when User_2 from Reqion_2 logs into the application, AbstractRoutingDataSource never gets called and Datasource_1 gets assigned.
It looks like Spring AbstractRoutingDataSource is caching the Datasouce.
Is there a way to change this behaviour of AbstractRoutingDataSource and get it working correctly?
You should provide more details for a better understanding.
I think the problem might be related to changing the tenant identifier. You may have a ThreadLocal storage to store the tenant identifier.
public class ThreadLocalStorage {
private static ThreadLocal<String> tenant = new ThreadLocal<>();
public static void setTenantName(String tenantName) {
tenant.set(tenantName);
}
public static String getTenantName() {
return tenant.get();
}
}
AbstractRoutingDataSource should use this to retrieve the tenantId
public class TenantAwareRoutingDataSource extends AbstractRoutingDataSource {
#Override
protected Object determineCurrentLookupKey() {
return ThreadLocalStorage.getTenantName();
}
}
And you should set the tenantId on each request for the current thread that is handling the request so that the following operations will be done on the correct database. For you may add a Spring Security filter to extract the tenant identifier from JWT token or from host subdomain.

Spring Data Solr #Transaction Commits

I currently have a setup where data is inserted into a database, as well as indexed into Solr. These two steps are wrapped in a spring-managed transaction via the #Transaction annotation. What I've noticed is that spring-data-solr issues an update with the following parameters whenever the transaction is closed : params{commit=true&softCommit=false&waitSearcher=true}
#Transactional
public void save(Object toSave){
dbRepository.save(toSave);
solrRepository.save(toSave);
}
The rate of commits into solr is fairly high, so ideally I'd like send data to the solr index, and have solr auto commit at regular intervals. I have the autoCommit (and autoSoftCommit) set in my solrconfig.xml, but since spring-data-solr is sending those commit parameters, it does a hard commit every time.
I'm aware that I can drop down to the SolrTemplate API and issue commits manually, I would like to keep the solr repository.save call within a spring-managed transaction if possible. Is there a way to modify the parameters that are sent to solr on commit?
After putting in an IDE debug breakpoint in org.springframework.data.solr.repository.support.SimpleSolrRepository here:
private void commitIfTransactionSynchronisationIsInactive() {
if (!TransactionSynchronizationManager.isSynchronizationActive()) {
this.solrOperations.commit(solrCollectionName);
}
}
I discovered that wrapping my code as #Transactional (and other details to actually enable the framework to begin/end code as a transaction) doesn't achieve what we expect with "Spring Data for Apache Solr". The stacktrace shows the Proxy and Transaction Interceptor classes for our code's Transactional scope but then it also shows the framework starting its own nested transaction with another Proxy and Transaction Interceptor of its own. When the framework exits its CrudRepository.save() method my code calls, the action to commit to Solr is done by the framework's nested transaction. It happens before our outer transaction is exited. So, the attempt to batch-process many saves with one commit at the end instead of one commit for every save is futile. It seems, for this area in my code, I'll have to make use of SolrJ to save (update) my entities to Solr and then have "my" transaction's exit be followed with a commit.
If using Spring Solr, I found using the SolrTemplate bean allows you to 'batch' updates when adding data to the Solr index. By using the bean for SolrTemplate, you can use "addBeans" method, which will add a collection to the index and not commit until the end of the transaction. In my case, I started out using solrClient.add() and taking up to 4 hours for my collection to get saved to the index by iterating over it, as it commits after every single save. By using solrTemplate.addBeans(Collect<?>), it finishes in just over 1 second, as the commit is on the entire collection. Here is a code snippet:
#Resource
SolrTemplate solrTemplate;
public void doReindexing(List<Image> images) {
if (images != null) {
/* CMSSolrImage is a class with #SolrDocument mappings.
* the List<Image> images is a collection pulled from my database
* I want indexed in Solr.
*/
List<CMSSolrImage> sImages = new ArrayList<CMSSolrImage>();
for (Image image : images) {
CMSSolrImage sImage = new CMSSolrImage(image);
sImages.add(sImage);
}
solrTemplate.saveBeans(sImages);
}
}
The way I've done something similar is to create a custom repository implementation of the save methods.
Interface for the repository:
public interface FooRepository extends SolrCrudRepository<Foo, String>, FooRepositoryCustom {
}
Interface for the custom overrides:
public interface FooRepositoryCustom {
public Foo save(Foo entity);
public Iterable<Foo> save(Iterable<Foo> entities);
}
Implementation of the custom overrides:
public class FooRepositoryImpl {
private SolrOperations solrOperations;
public SolrSampleRepositoryImpl(SolrOperations fooSolrOperations) {
this.solrOperations = fooSolrOperations;
}
#Override
public Foo save(Foo entity) {
Assert.notNull(entity, "Cannot save 'null' entity.");
registerTransactionSynchronisationIfSynchronisationActive();
this.solrOperations.saveBean(entity, 1000);
commitIfTransactionSynchronisationIsInactive();
return entity;
}
#Override
public Iterable<Foo> save(Iterable<Foo> entities) {
Assert.notNull(entities, "Cannot insert 'null' as a List.");
if (!(entities instanceof Collection<?>)) {
throw new InvalidDataAccessApiUsageException("Entities have to be inside a collection");
}
registerTransactionSynchronisationIfSynchronisationActive();
this.solrOperations.saveBeans((Collection<? extends T>) entities, 1000);
commitIfTransactionSynchronisationIsInactive();
return entities;
}
private void registerTransactionSynchronisationIfSynchronisationActive() {
if (TransactionSynchronizationManager.isSynchronizationActive()) {
registerTransactionSynchronisationAdapter();
}
}
private void registerTransactionSynchronisationAdapter() {
TransactionSynchronizationManager.registerSynchronization(SolrTransactionSynchronizationAdapterBuilder
.forOperations(this.solrOperations).withDefaultBehaviour());
}
private void commitIfTransactionSynchronisationIsInactive() {
if (!TransactionSynchronizationManager.isSynchronizationActive()) {
this.solrOperations.commit();
}
}
}
and you also need to provide a SolrOperations bean for the right solr core:
#Configuration
public class FooSolrConfig {
#Bean
public SolrOperations getFooSolrOperations(SolrClient solrClient) {
return new SolrTemplate(solrClient, "foo");
}
}
Footnote: auto commit is (to my mind) conceptually incompatible with a transaction. An auto commit is a promise from solr that it will try to start to write it to disk within a certain time limit. Many things might stop that from actually happening however - a timely power or hardware failure, errors between the document and the schema, etc. But the client won't know that solr failed to keep its promise, and the transaction will see a success when it actually failed.

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