topic Re: question about Activit Transactions interfering with other transactions? in Alfresco Archive

question about Activit Transactions interfering with other transactions?

aruna — Fri, 06 Dec 2013 21:12:50 GMT

Hi,I am new to Activiti and am writing a simple scenario where I create a service task. This service task calls a delegate which is turn calls another service which interacts with database. I want my service to be a black box to activiti. All I need is that it calls the service and prints out the o

Re: question about Activit Transactions interfering with other transactions?

raviraj — Sun, 08 Dec 2013 15:26:08 GMT

Dear Aruna, you can change database configuration.
<code>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" >
<property name="driverClassName" value="" />
<property name="url" value="" />
<property name="username" value="" />
<property name="password" value="" />
<property name="defaultAutoCommit" value="false" />
</bean>

<bean id="processEngineConfiguration" class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration">

<property name="dataSource" ref="dataSource" />
</code>

Re: question about Activit Transactions interfering with other transactions?

aruna — Mon, 09 Dec 2013 13:30:29 GMT

This is my database configuration.
<code>
<!– Begin Activiti Setup –>
<bean id="dataSource"
class="org.springframework.jdbc.datasource.SimpleDriverDataSource">
<property name="driverClass" value="org.h2.Driver" />
<property name="url" value="jdbc:h2:mem:activiti;DB_CLOSE_DELAY=1000" />
<property name="username" value="sa" />
<property name="password" value="sa" />
</bean>
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />

</bean>

<bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration">
<property name="dataSource" ref="dataSource" />
<property name="transactionManager" ref="transactionManager" />
<property name="databaseSchemaUpdate" value="true" />
<property name="jobExecutorActivate" value="false" />
<property name="deploymentResources">
   <list>
    <!– <value>classpathrder-management.bpmn </value> –>
    <value>classpathrder-management.bpmn
    </value>
   </list>
</property>
</bean>

<bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
<property name="processEngineConfiguration" ref="processEngineConfiguration" />
</bean>

<bean id="repositoryService" factory-bean="processEngine"
factory-method="getRepositoryService" />
<bean id="runtimeService" factory-bean="processEngine"
factory-method="getRuntimeService" />
<bean id="taskService" factory-bean="processEngine"
factory-method="getTaskService" />
<bean id="historyService" factory-bean="processEngine"
factory-method="getHistoryService" />
<bean id="managementService" factory-bean="processEngine"
factory-method="getManagementService" />
<!– End Activiti Setup –>

<!– Business Process Implementation –>
<bean id="businessProcessService"
class="com.efx.pet.service.business_process.ActivitiBusinessProcessService">
<property name="activitiProcessEngine" ref="processEngine" />
</bean>
</code>

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Tue, 10 Dec 2013 12:44:00 GMT

If you use different databases, you SHOULD use JTA with XA-transactions. if you don't, the transactions won't be synchronized.

In your case, you call your services from within activiti. When activiti executes the process, it creates a new (activiti) transaction. The process reaches the user-task and does a service-call to your code. This service-call creates a new transaction, does the call, closes the transaction/session and returns the entity to activiti. Activiti uses the objects and uses some fields which are marked as lazy-loaded. Since your service-call-transaction is closed, the missing referenced entities cannot be fetched and you get an exeption.

To fix this, you can either:
1) Use XA-transactions IF writes to your service should be in-sync with writes to activiti
2) If you only read your own service-DB, you should make sure your service returned fully usable objects (with all needed referenced entities eagerly fetched before the method returns the result).

Re: question about Activit Transactions interfering with other transactions?

aruna — Tue, 10 Dec 2013 16:05:33 GMT

Thanks Fredrik. You basically got the crux of my problem except for one small difference. The problem is not happening when I am trying to access the object in Activiti. The problem is actually occurring within my service call itself.
The reason I asked the question was because this same method works fine when I call it from a JUNIT without using Activiti,
Like I mentioned if i was calling my service from a JUNIT the same method is working fine but when I am making the call to service from Activity, I get a Lazy loading exception IN MY service. So is there a possibility that the transaction that is created by Activity , is interfering with the transactions of my service?

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Wed, 11 Dec 2013 09:41:42 GMT

If you're NOT using the same database and NOT using the same transaction-manager, that seems very unlikely that it's the Activiti transaction that is causing this.

How do you" wire" in your services in the activiti-service task?

Re: question about Activit Transactions interfering with other transactions?

aruna — Wed, 11 Dec 2013 14:06:52 GMT

The OrderManagementDelegate calls my Service.
The service task uses Expression to call out the method in the Delegate:
<code>
#{orderManagementDelegate.checkout(execution)}
</code>
Here is what I have in context.xml
<code>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
<property name="driverClassName" value="org.h2.Driver" />
<property name="url" value="jdbc:h2:mem:activiti;DB_CLOSE_DELAY=1000" />
<property name="username" value="sa" />
<property name="password" value="sa" />
</bean>
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource" />

</bean>

<bean id="processEngineConfiguration" class="org.activiti.spring.SpringProcessEngineConfiguration">
<property name="dataSource" ref="dataSource" />
<property name="transactionManager" ref="transactionManager" />
<property name="databaseSchemaUpdate" value="true" />
<property name="jobExecutorActivate" value="false" />
<property name="deploymentResources">
   <list>
    <!– <value>classpathrder-management.bpmn </value> –>
    <value>classpathrder-management.bpmn
    </value>
   </list>
</property>
</bean>

<bean id="processEngine" class="org.activiti.spring.ProcessEngineFactoryBean">
<property name="processEngineConfiguration" ref="processEngineConfiguration" />
</bean>

<bean id="repositoryService" factory-bean="processEngine"
factory-method="getRepositoryService" />
<bean id="runtimeService" factory-bean="processEngine"
factory-method="getRuntimeService" />
<bean id="taskService" factory-bean="processEngine"
factory-method="getTaskService" />
<bean id="historyService" factory-bean="processEngine"
factory-method="getHistoryService" />
<bean id="managementService" factory-bean="processEngine"
factory-method="getManagementService" />
<!– End Activiti Setup –>

<!– Business Process Implementation –>
<bean id="businessProcessService"
class="com.efx.pet.service.business_process.ActivitiBusinessProcessService">
<property name="activitiProcessEngine" ref="processEngine" />
</bean>

<!– <tx:annotation-driven transaction-manager="transactionManager"/> –>

<bean id="orderManagementService"
class="com.efx.pet.service.ordermanagement.impl.OrderManagementServiceImpl"
init-method="onInit" />

<bean id="orderManagementDelegate"
class="com.efx.pet.service.business_process.delegate.OrderManagementDelegate" />
</code>

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Thu, 12 Dec 2013 07:28:18 GMT

I see you commented out the <tx:annotation-driven part. How do your services get hold of the transaction/connection? I don't see any interceptors in your context-file that do this.

Just a question, is there any reason why you don't use the same DB for activiti and your services? This would simplify the setup a lot and you'll have guaranteed sync of activiti's and your entities, without setting up XA-transations.

Re: question about Activit Transactions interfering with other transactions?

aruna — Thu, 12 Dec 2013 15:19:31 GMT

We are using activity as a workflow engine and for what I am doing I don't want it to rollback the entire transaction if it fails in the service I am calling. Also we are using a thirdparty in our services which maintains its own transactions and the way they are dealing with it is different. Also the entities that are used in Activity are not the same as what we use in the service. We pass XMLBeans among services and then service maps it to the entities (and back to XMLbeans) as and when required. Hence Activity has no idea of what the entities are in the service. That is why I mentioned that I need the service being called in Activity as a blackbox.

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Fri, 13 Dec 2013 08:19:37 GMT

Okay, makes sense. My previous question was cut off due to XML-tag usage inline, i suppose.

Again: I see you have commented out the tx:annotation-driven… How are the transactions in YOUR services started/closed/controlled, if they are not annotation-driven?

Re: question about Activit Transactions interfering with other transactions?

aruna — Fri, 13 Dec 2013 15:25:02 GMT

Yes they are annotation driven. and they are all managed within broadleaf, an open source order management system that my services uses.

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Mon, 16 Dec 2013 07:21:06 GMT

Yes, but why is that piece of the XML commented out? This way, transactions aren't hooked up in the services you use…

Re: question about Activit Transactions interfering with other transactions?

aruna — Mon, 16 Dec 2013 18:55:28 GMT

I don't want to pass any transactions from activity to my services. As I mentioned my service should be a black box to Activity. You can assume that my service just returns a String back to Activity. What happens within my services should not matter to activity.

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Tue, 17 Dec 2013 08:48:44 GMT

Aruna, If I should consider it as a black box, why are you asking questions about transactions IN your services? I just want to help you and figure out how your services get THEIR transactions wired in, regardless of actviti's transactions… If the black box doesn't work as it should, it's either not configured the way it should or using the wrong transaction-manager.

Re: question about Activit Transactions interfering with other transactions?

aruna — Tue, 17 Dec 2013 15:37:49 GMT

The reason I was asking was because the service works fine when I call it from a Junit test but when I started calling it from Activiti I started getting the exception I mentioned in my post. I was wondering if somehow Activit's transaction was interfering with my service. Since I don't know the internals of Activiti I thought I would ask to see if that was possible. From what I understand, Activiti would open a connection and then call my service, but my service will create its own connections and transactions, but could the open connection/transaction of Activity cause any problems?

Re: question about Activit Transactions interfering with other transactions?

frederikherema1 — Wed, 18 Dec 2013 08:34:01 GMT

If activiti uses TransactionManager 1 and your services use TransactionManager 2, there is NO way of activiti interfering with the service-transactions. However, in your examples, I don't see how the transactions for your black-box services are configured. Make sure the use a different transaction-manager for the behaviour you're trying to do.

If the JUnit-test works, you should just take that spring-context and throw in the activiti-beans and it should continue to work.

Re: question about Activit Transactions interfering with other transactions?

amenting — Tue, 26 Apr 2016 14:45:55 GMT

For me, the problem only ceased to exist after i injected the entity manager into the jpaEntityManagerFactory property, but maybe that is just because i am configuring the spring boot way in code (everything else is pretty standard spring boot default setup - transaction management should be set up in boot by default, if i read the documentation correctly, but it did not work for me in version 5.20.0).

<java>
@Bean
SpringProcessEngineConfiguration processEngineConfiguration(
   EntityManagerFactory entityManagerFactory,
   Environment env, DataSource dataSource,
   PlatformTransactionManager transactionManager, CustomGroupManagerFactory groupManagerFactory, CustomUserManagerFactory userManagerFactory) {

SpringProcessEngineConfiguration config = new SpringProcessEngineConfiguration();
config.setTransactionManager(transactionManager);
config.setDataSource(dataSource);
config.setDatabaseSchemaUpdate("true");
config.setJobExecutorActivate(false);

                //enable transaction integration
config.setJpaEntityManagerFactory(entityManagerFactory);
config.setJpaHandleTransaction(true);
//config.setTransactionsExternallyManaged(true);

config.setDeploymentResources(new Resource[] {new ClassPathResource("/processes/myprocess.bpmn20.xml")});
config.setCustomSessionFactories(Arrays.asList(userManagerFactory, groupManagerFactory));

if(Arrays.asList(env.getActiveProfiles()).contains("development") && devMailServerActive){
   config.setMailServerPort(devMailServerPort);
}
else if(mailServerPort>0){
   config.setMailServerPort(mailServerPort);
}
return config;
}
</java>