Wiring Activiti as a Spring Bean in Grails

Question

I'm trying to create a Grails application that uses Activiti for its process engine. To that end, I'd like the main Activiti service classes (RuntimeService, TaskService, etc.) to be wired as Spring beans.

I believe that I have the wiring setup correctly, but when I run a simple integration test that calls the runtime service, I get an error that Spring couldn't open a hibernate session (see Full Stack Trace, below).

Update: I can start the application with run-app, then call a controller action which calls my service, and it all works. So, the Activiti wiring works, it just has some conflict with the Grails Integration Testing mixin.

I really want the Activiti services to use the same datasource connection as the Grails application. I'm assuming that the problem is that Activiti is trying to create its own ConnectionHolder instance, when Grails already has one setup for the integration tests.

My specific (and possibly misguided) question I have is, how do I configure my Activiti ProcessEngine so that it uses the same data source and hibernate connection that my Grails application does?

The more general question is, how can I best make the Activiti services available to my Grails application? I've looked at the Activiti plugin for grails, and the source of it has helped me get this far. However, I'd rather not use that plugin; it's not using the latest activiti, development on it is not terribly active, and it's not really what I need in any case.

Full Stack Trace

| Failure:  start approver request(com.package.MyServiceSpec)
|  org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is java.lang.IllegalStateException: Already value [org.springframework.jdbc.datasource.ConnectionHolder@7f2e1821] for key [org.springframework.jdbc.datasource.LazyConnectionDa
    at grails.test.mixin.integration.IntegrationTestMixin.initIntegrationTest(IntegrationTestMixin.groovy:58)
    at org.spockframework.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:138)
    at org.spockframework.runtime.extension.builtin.JUnitFixtureMethodsExtension$FixtureType$FixtureMethodInterceptor.intercept(JUnitFixtureMethodsExtension.java:145)
    at org.spockframework.runtime.extension.MethodInvocation.proceed(MethodInvocation.java:84)
    at org.spockframework.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:138)
    at org.spockframework.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:138)
    at org.spockframework.util.ReflectionUtil.invokeMethod(ReflectionUtil.java:138)
Caused by: org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is java.lang.IllegalStateException: Already value [org.springframework.jdbc.datasource.ConnectionHolder@7f2e1821] for key [org.springframework.jdbc.datasource.LazyConn
    ... 7 more
Caused by: java.lang.IllegalStateException: Already value [org.springframework.jdbc.datasource.ConnectionHolder@7f2e1821] for key [org.springframework.jdbc.datasource.LazyConnectionDataSourceProxy@1b7aeb] bound to thread [main]
    ... 7 more
| Completed 1 integration test, 1 failed in 0m 1s

resources.groovy

import org.activiti.engine.ProcessEngine
import org.activiti.spring.ProcessEngineFactoryBean
import org.activiti.explorer.form.*
import org.activiti.spring.SpringProcessEngineConfiguration
import grails.util.Environment
//These imports are only needed in the test environment for building an h2 database for activiti during unit tests
import org.springframework.jdbc.datasource.DataSourceTransactionManager
import org.springframework.jdbc.datasource.SimpleDriverDataSource

beans = {            
    processEngineConfig(SpringProcessEngineConfiguration) {
        dataSource = ref('dataSource')
        transactionManager = ref('transactionManager')
        databaseType = 'oracle'
        databaseSchema = 'OURSCHEMA'
        databaseSchemaUpdate = false
        jobExecutorActivate = true
    }

    processEngine(ProcessEngineFactoryBean) {
        processEngineConfiguration = ref("processEngineConfig")
    }

    runtimeService(processEngine: "getRuntimeService")
    repositoryService(processEngine: "getRepositoryService")
    taskService(processEngine: "getTaskService")
    managementService(processEngine: "getManagementService")
    historyService(processEngine: "getHistoryService")
    formService(processEngine: "getFormService")
}

Service class

class MyService {

    def foapAuthFoapService
    def processEngine
    def runtimeService
    def repositoryService
    def taskService
    def managementService
    def historyService
    def formService

    /**
    * Start the activiti process.
    * 
    */
    def startRequest(String requester, String subject, String designatedApprover) {
        runtimeService.startProcessInstanceByKey('MyProcess', ["requester": requester, "subject": subject, "designatedApprover": designatedApprover])
    }
}

Spock Test

    def "start request"() {
        setup:
            def approverRequest = service.startRequest(requester, subject, designatedApprover)
            def variables = runtimeService.getVariables(approverRequest.id) //approverRequest.getProcessVariables()     
        expect:
            approverRequest instanceof ProcessInstance
            variables.entrySet().contailsAll(["designatedApprover": designatedApprover, "requester": requester, "subject": subject].entrySet())
        where:
            requester | subject |   designatedApprover
            "abc123"  | "def456"|   "hij789"
    }

Answer 1

we at Alephsa are maintaining the grails activiti plugin updated to the latest version of Activiti (5.17) and we are working to update to version 6. You can find the plugin at bintray also with the grails activiti spring security plugin. In our github account you can find the source code to guide you in your efforts.

Regards.