How to use multiple Zookeeper with distributed state machine? - apache-zookeeper

Question

I'm trying to use distributed states in my application with zookeeper just like in the Spring document, with only one difference. My application works fine with one zookeeper but I need multiple zookeeper address. Here is my configuration:
import jpapersistsm.enums.Events;
import jpapersistsm.enums.States;
import lombok.extern.slf4j.Slf4j;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.statemachine.config.EnableStateMachineFactory;
import org.springframework.statemachine.config.StateMachineConfigurerAdapter;
import org.springframework.statemachine.config.StateMachineFactory;
import org.springframework.statemachine.config.builders.StateMachineConfigurationConfigurer;
import org.springframework.statemachine.config.builders.StateMachineStateConfigurer;
import org.springframework.statemachine.config.builders.StateMachineTransitionConfigurer;
import org.springframework.statemachine.data.jpa.JpaPersistingStateMachineInterceptor;
import org.springframework.statemachine.data.jpa.JpaStateMachineRepository;
import org.springframework.statemachine.ensemble.StateMachineEnsemble;
import org.springframework.statemachine.listener.StateMachineListener;
import org.springframework.statemachine.listener.StateMachineListenerAdapter;
import org.springframework.statemachine.persist.StateMachineRuntimePersister;
import org.springframework.statemachine.service.DefaultStateMachineService;
import org.springframework.statemachine.service.StateMachineService;
import org.springframework.statemachine.state.State;
import org.springframework.statemachine.zookeeper.ZookeeperStateMachineEnsemble;
import java.util.EnumSet;
#Slf4j
#Configuration
#EnableStateMachineFactory
public class JpaPersistStateMachineConfiguration extends StateMachineConfigurerAdapter<States, Events> {
#Autowired
public JpaStateMachineRepository jpaStateMachineRepository;
private Logger logger = LoggerFactory.getLogger(JpaPersistStateMachineConfiguration.class);
#Override
public void configure(StateMachineStateConfigurer<States, Events> states) throws Exception{
states
.withStates()
.initial(States.ORDERED)
.end(States.PAYED)
.end(States.CANCELLED)
.states(EnumSet.allOf(States.class));
}
#Override
public void configure(StateMachineTransitionConfigurer<States,Events> transitions) throws Exception {
transitions
.withExternal().source(States.ORDERED).target(States.ASSEMBLED).event(Events.assemble).and()
.withExternal().source(States.ASSEMBLED).target(States.DELIVERED).event(Events.deliver).and()
.withExternal().source(States.DELIVERED).target(States.PAYED).event(Events.payment_received).and()
.withExternal().source(States.ORDERED).target(States.CANCELLED).event(Events.cancel).and()
.withExternal().source(States.ASSEMBLED).target(States.CANCELLED).event(Events.cancel).and()
.withExternal().source(States.DELIVERED).target(States.CANCELLED).event(Events.cancel);
}
#Override
public void configure(StateMachineConfigurationConfigurer<States,Events> config) throws Exception{
config
.withDistributed()
.ensemble(stateMachineEnsemble())
.and()
.withPersistence()
.runtimePersister(stateMachineRuntimePersister())
.and()
.withConfiguration()
.autoStartup(true);
}
#Bean
public StateMachineEnsemble<States, Events> stateMachineEnsemble() throws Exception {
return new ZookeeperStateMachineEnsemble<States, Events>(curatorClient(), "/app");
}
#Bean
public CuratorFramework curatorClient() throws Exception {
CuratorFramework client = CuratorFrameworkFactory
.builder()
.defaultData(new byte[0])
.retryPolicy(new ExponentialBackoffRetry(1000, 3))
.connectString("localhost:2181,localhost:2182,localhost:2183")
.build();
client.start();
return client;
}
#Bean
public StateMachineRuntimePersister<States,Events,String> stateMachineRuntimePersister(){
return new JpaPersistingStateMachineInterceptor<>(jpaStateMachineRepository);
}
#Bean
public StateMachineService<States,Events> stateMachineService (
StateMachineFactory<States,Events> stateMachineFactory,
StateMachineRuntimePersister<States,Events,String> stateMachineRuntimePersister){
return new DefaultStateMachineService<>(stateMachineFactory, stateMachineRuntimePersister);
}
#Bean
public StateMachineListener<States, Events> listener() {
return new StateMachineListenerAdapter<States, Events>() {
#Override
public void stateChanged(State<States, Events> from, State<States, Events> to) {
logger.info("*** listener: in state changed");
if (from == null) logger.info("*** state machine initialised in state {}", to.getId());
else logger.info("*** state changed from {} to {}", from.getId(), to.getId());
}
};
}
}
And my REST Controller class is:
import jpapersistsm.enums.Events;
import jpapersistsm.enums.States;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.statemachine.StateMachine;
import org.springframework.statemachine.listener.StateMachineListener;
import org.springframework.statemachine.service.StateMachineService;
import org.springframework.util.ObjectUtils;
import org.springframework.web.bind.annotation.*;
import java.util.Map;
#RestController
#RequestMapping("/jpapersist")
public class RestServiceController {
#Autowired
public StateMachineService<States, Events> stateMachineService;
#Autowired
public StateMachineListener listener;
public StateMachine<States, Events> stateMachine;
public Logger logger = LoggerFactory.getLogger(RestServiceController.class);
#RequestMapping(value="/init", method= RequestMethod.POST)
public void init(#RequestBody Map<String,String> parameters){
logger.info("\n*** inside of state machine controller : INIT ");
try {
stateMachine = getStateMachine(parameters.get("guid"));
} catch (Exception e) {
e.printStackTrace();
}
logger.info("\n*** state machine initialized to state: {}", stateMachine.getState().getId().name());
}
/***
Synchronized method to obtain persisted state machine from database.
*/
public synchronized StateMachine<States,Events> getStateMachine(String machineId) throws Exception {
if (stateMachine == null) {
stateMachine = stateMachineService.acquireStateMachine(machineId);
stateMachine.addStateListener(listener);
stateMachine.start();
} else if (!ObjectUtils.nullSafeEquals(stateMachine.getId(), machineId)) {
stateMachineService.releaseStateMachine(stateMachine.getId());
stateMachine.stop();
stateMachine = stateMachineService.acquireStateMachine(machineId);
stateMachine.addStateListener(listener);
stateMachine.start();
}
return stateMachine;
}
}
When I send a request for initialize a state machine, getting an error like:
Unable to persist stateMachineContext
Caused by: org.hibernate.id.IdentifierGenerationException: ids for this class must be manually assigned before calling save(): org.springframework.statemachine.data.jpa.JpaRepositoryStateMachine
at org.hibernate.id.Assigned.generate(Assigned.java:33) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:119) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.entityIsTransient(DefaultPersistEventListener.java:192) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:135) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.event.internal.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:62) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.internal.SessionImpl.firePersist(SessionImpl.java:800) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at org.hibernate.internal.SessionImpl.persist(SessionImpl.java:785) ~[hibernate-core-5.3.10.Final.jar:5.3.10.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_222]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_222]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_222]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_222]
at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:350) ~[spring-orm-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at com.sun.proxy.$Proxy117.persist(Unknown Source) ~[na:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_222]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_222]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_222]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_222]
at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:309) ~[spring-orm-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at com.sun.proxy.$Proxy117.persist(Unknown Source) ~[na:na]
at org.springframework.data.jpa.repository.support.SimpleJpaRepository.save(SimpleJpaRepository.java:535) ~[spring-data-jpa-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_222]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_222]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_222]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_222]
at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:359) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:200) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:644) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:608) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$invoke$3(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:595) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:59) ~[spring-data-commons-2.1.10.RELEASE.jar:2.1.10.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:295) ~[spring-tx-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.1.9.RELEASE.jar:5.1.9.RELEASE]
... 111 common frames omitted
The state of the machine seems to changed, but could not persist on db. As I said, the problem is my curator configuration. Because it works fine when I define connectString with single Zookeeper like
.connectString("localhost:2181")
I'm new to Zookeeper and Curator, and open to any help. Thanks in advance.

Answer 1

The problem is with this configuration:
.withConfiguration()
.autoStartup(true);
Because it tries to start the machine, before having a machine id.