Embedded Process Engine Configuration

Now that you have set up the project with the correct Maven dependencies, we can start configuring the process engine.

Configure an Embedded Process Engine

Add the following Spring beans to the LoanApplication class as follows:

package org.operaton.bpm.getstarted.loanapproval;

import javax.sql.DataSource;

import org.operaton.bpm.engine.HistoryService;
import org.operaton.bpm.engine.ManagementService;
import org.operaton.bpm.engine.ProcessEngine;
import org.operaton.bpm.engine.RepositoryService;
import org.operaton.bpm.engine.RuntimeService;
import org.operaton.bpm.engine.TaskService;
import org.operaton.bpm.engine.spring.ProcessEngineFactoryBean;
import org.operaton.bpm.engine.spring.SpringProcessEngineConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.transaction.PlatformTransactionManager;

@Configuration
public class LoanApplicationContext {

  @Bean
  public DataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName("org.h2.Driver");
    dataSource.setUrl("jdbc:h2:mem:process-engine;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE");
    dataSource.setUsername("sa");
    dataSource.setPassword("");
    return dataSource;
  }

  @Bean
  public PlatformTransactionManager transactionManager(DataSource dataSource) {
    return new DataSourceTransactionManager(dataSource);
  }

  @Bean
  public SpringProcessEngineConfiguration engineConfiguration(DataSource dataSource, PlatformTransactionManager transactionManager) {
    SpringProcessEngineConfiguration configuration = new SpringProcessEngineConfiguration();

    configuration.setProcessEngineName("engine");
    configuration.setDataSource(dataSource);
    configuration.setTransactionManager(transactionManager);
    configuration.setDatabaseSchemaUpdate("true");
    configuration.setJobExecutorActivate(false);

    return configuration;
  }

  @Bean
  public ProcessEngineFactoryBean engineFactory(SpringProcessEngineConfiguration engineConfiguration) {
    ProcessEngineFactoryBean factoryBean = new ProcessEngineFactoryBean();
    factoryBean.setProcessEngineConfiguration(engineConfiguration);
    return factoryBean;
  }

  @Bean
  public ProcessEngine processEngine(ProcessEngineFactoryBean factoryBean) throws Exception {
    return factoryBean.getObject();
  }

  @Bean
  public RepositoryService repositoryService(ProcessEngine processEngine) {
    return processEngine.getRepositoryService();
  }

  @Bean
  public RuntimeService runtimeService(ProcessEngine processEngine) {
    return processEngine.getRuntimeService();
  }

  @Bean
  public TaskService taskService(ProcessEngine processEngine) {
    return processEngine.getTaskService();
  }

  @Bean
  public HistoryService historyService(ProcessEngine processEngine) {
    return processEngine.getHistoryService();
  }

  @Bean
  public ManagementService managementService(ProcessEngine processEngine) {
    return processEngine.getManagementService();
  }
}

This bootstraps a process engine with an in-memory H2 database and makes the engine as well as its API services available as Spring beans.

After you added the beans to the application context, perform a full Maven build and redeploy the application. In the logfile of the Apache Tomcat server you should be able to see the initialization of the process-engine:

INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'engine' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.engine.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'history' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.history.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'identity' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.identity.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'case.engine' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.case.engine.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'case.history' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.case.history.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'decision.engine' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.decision.engine.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03016 Performing database operation 'create' on component 'decision.history' with resource 'org/operaton/bpm/engine/db/create/activiti.h2.create.decision.history.sql' INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03067 No history level property found in database INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-03065 Creating historyLevel property in database for level: HistoryLevelAudit(name=audit, id=2) INFO org.operaton.commons.logging.BaseLogger.logInfo ENGINE-00001 Process Engine engine created.

Configure an Embedded Process Engine​

Configure an Embedded Process Engine