无法在 Spring Boot 中实现 Drools KieSession Persistence

Question

我试图在 Spring Boot Maven 项目中使用KieSession的持久性功能实现 Drools。 按照此文档进行实施。 能够在普通的 Java 应用程序中做到这一点，但我在 Spring Boot 应用程序中尝试这样做时遇到了异常。

下面是实现。

项目结构

配置类

@Configuration
public class PersistentDroolConfig {

    public static Long KIE_SESSION_ID;
    private final KieServices kieServices = KieServices.Factory.get();

    @Bean
    public KieSession kieSession() {
        KieSession kieSession = kieServices.getStoreServices().newKieSession(getKieBase(), null, getEnv());
        PersistentDroolConfig.KIE_SESSION_ID = kieSession.getIdentifier();
        return kieSession;
    }

    public KieServices getKieServices() {
        initDataSource();
        return kieServices;
    }

    public KieBase getKieBase() {
        KieFileSystem kieFileSystem = kieServices.newKieFileSystem();
        kieFileSystem.write(ResourceFactory.newClassPathResource("rules/rules.drl"));
        final KieRepository kieRepository = kieServices.getRepository();
        kieRepository.addKieModule(kieRepository::getDefaultReleaseId);
        KieBuilder kb = kieServices.newKieBuilder(kieFileSystem);
        kb.buildAll();
        KieModule kieModule = kb.getKieModule();
        KieContainer kieContainer = kieServices.newKieContainer(kieModule.getReleaseId());
        return kieContainer.getKieBase();
    }

    public Environment getEnv() {
        Environment env = kieServices.newEnvironment();
        env.set(EnvironmentName.ENTITY_MANAGER_FACTORY, Persistence.createEntityManagerFactory("org.drools.persistence.jpa"));
        env.set(EnvironmentName.TRANSACTION_MANAGER, TransactionManagerServices.getTransactionManager());
        return env;
    }

    private void initDataSource() {
        PoolingDataSource ds = new PoolingDataSource();
        ds.setUniqueName("jdbc/BitronixJTADataSource");
        ds.setClassName("com.mysql.cj.jdbc.MysqlXADataSource");
        ds.setMaxPoolSize(3);
        ds.setAllowLocalTransactions(true);
        ds.getDriverProperties().put("user", "root");
        ds.getDriverProperties().put("password", "1234");
        ds.getDriverProperties().put("URL", "jdbc:mysql://localhost:3306/drool_demo");
        ds.init();
    }
}

控制器类

@RestController
public class OfferController {

    @Autowired
    private KieSession kieSession;

    @GetMapping("/order/{card-type}/{price}")
    public Order order(@PathVariable("card-type") String cardType, @PathVariable int price) {
        Order order = new Order(cardType, price);
        kieSession.insert(order);
        kieSession.fireAllRules();
        return order;
    }
}

事实类

public class Order implements Serializable {

    private String name;
    private String cardType;
    private int discount;
    private int price;

    public Order(String cardType, int price) {
        this.cardType = cardType;
        this.price = price;
    }

    // setters and getters

    // toString()
}

持久化文件

<persistence version="2.0"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd
                      http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_2_0.xsd"
    xmlns:orm="http://java.sun.com/xml/ns/persistence/orm"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/persistence">
    <persistence-unit name="org.drools.persistence.jpa"
        transaction-type="JTA">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <jta-data-source>jdbc/BitronixJTADataSource</jta-data-source>
        <class>org.drools.persistence.info.SessionInfo</class>
        <class>org.drools.persistence.info.WorkItemInfo</class>
        <properties>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect" />
            <property name="hibernate.max_fetch_depth" value="3" />
            <property name="hibernate.hbm2ddl.auto" value="create" />
            <property name="hibernate.show_sql" value="true" />
            <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.BTMTransactionManagerLookup" />
        </properties>
    </persistence-unit>
</persistence>

pom.xml文件中包含的依赖如下：

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.github.marcus-nl.btm</groupId>
            <artifactId>btm</artifactId>
            <version>3.0.0-mk1</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-decisiontables</artifactId>
            <version>${drools-version}</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-core</artifactId>
            <version>${drools-version}</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-compiler</artifactId>
            <version>${drools-version}</version>
        </dependency>
        <dependency>
            <groupId>org.drools</groupId>
            <artifactId>drools-persistence-jpa</artifactId>
            <version>${drools-version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

错误堆栈跟踪：

Caused by: org.hibernate.engine.jndi.JndiException: Unable to lookup JNDI name [jdbc/BitronixJTADataSource]

Caused by: javax.naming.NameNotFoundException: unable to find a bound object at name 'jdbc/BitronixJTADataSource'

该项目也可以在 此存储库中找到。

更新1：

实施@jccampanero 的回答后，我有一个更新的堆栈跟踪：

Caused by: org.hibernate.HibernateException: Unable to perform isolated work

Caused by: java.sql.SQLSyntaxErrorException: Table 'drool_demo.sessioninfo_id_seq' doesn't exist

更新 2：

在进一步挖掘之后，我发现 Drools 由于一些语法错误而没有制作必要的表格。 由于 Stackoverflow 有文本限制，这里只发布了重要的异常消息。 这是：

Hibernate: drop table if exists SessionInfo
Hibernate: drop table if exists WorkItemInfo
Hibernate: create table SessionInfo (id bigint not null auto_increment, lastModificationDate datetime, rulesByteArray longblob, startDate datetime, OPTLOCK integer, primary key (id)) type=MyISAM
2020-10-09 23:49:59.554  WARN 11376 --- [           main] o.h.t.s.i.ExceptionHandlerLoggedImpl     : GenerationTarget encountered exception accepting command : Error executing DDL "create table SessionInfo (id bigint not null auto_increment, lastModificationDate datetime, rulesByteArray longblob, startDate datetime, OPTLOCK integer, primary key (id)) type=MyISAM" via JDBC Statement


org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "create table SessionInfo (id bigint not null auto_increment, lastModificationDate datetime, rulesByteArray longblob, startDate datetime, OPTLOCK integer, primary key (id)) type=MyISAM" via JDBC Statement

Caused by: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'type=MyISAM' at line 1

Hibernate: create table WorkItemInfo (workItemId bigint not null auto_increment, creationDate datetime, name varchar(255), processInstanceId bigint not null, state bigint not null, OPTLOCK integer, workItemByteArray longblob, primary key (workItemId)) type=MyISAM
2020-10-09 23:49:59.556  WARN 11376 --- [           main] o.h.t.s.i.ExceptionHandlerLoggedImpl     : GenerationTarget encountered exception accepting command : Error executing DDL "create table WorkItemInfo (workItemId bigint not null auto_increment, creationDate datetime, name varchar(255), processInstanceId bigint not null, state bigint not null, OPTLOCK integer, workItemByteArray longblob, primary key (workItemId)) type=MyISAM" via JDBC Statement

org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "create table WorkItemInfo (workItemId bigint not null auto_increment, creationDate datetime, name varchar(255), processInstanceId bigint not null, state bigint not null, OPTLOCK integer, workItemByteArray longblob, primary key (workItemId)) type=MyISAM" via JDBC Statement

Caused by: java.sql.SQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'type=MyISAM' at line 1

Answer 1

我认为您的配置有问题。 该getKieServices的方法PersistentDroolConfig类则永远不会调用和，因此，无论是方法initDataSource它初始化您的数据源。

也许您可以尝试修改PersistentDroolConfig ，如下所示：

@Configuration
public class PersistentDroolConfig {

    public static Long KIE_SESSION_ID;

    private KieServices kieServices;

    @PostContruct
    private void init() {
        this.initDataSource();
        this.kieServices = KieServices.Factory.get();
    }

    @Bean
    public KieSession kieSession() {
        KieSession kieSession;
        if (KIE_SESSION_ID == null) {
            kieSession = createNewKieSession();
            KIE_SESSION_ID = kieSession.getIdentifier();
            return kieSession;
        } else {
            kieSession = getPersistentKieSession();
            KIE_SESSION_ID = kieSession.getIdentifier();
            return kieSession;
        }
    }

    public KieBase getKieBase() {
        KieFileSystem kieFileSystem = kieServices.newKieFileSystem();
        kieFileSystem.write(ResourceFactory.newClassPathResource("rules/rules.drl"));
        final KieRepository kieRepository = kieServices.getRepository();
        kieRepository.addKieModule(new KieModule() {
            @Override
            public ReleaseId getReleaseId() {
                return kieRepository.getDefaultReleaseId();
            }
        });
        KieBuilder kb = kieServices.newKieBuilder(kieFileSystem);
        kb.buildAll();
        KieModule kieModule = kb.getKieModule();
        KieContainer kieContainer = kieServices.newKieContainer(kieModule.getReleaseId());
        KieBase kieBase = kieContainer.getKieBase();
        return kieBase;
    }

    public Environment getEnv() {
        Environment env = kieServices.newEnvironment();
        env.set(EnvironmentName.ENTITY_MANAGER_FACTORY, Persistence.createEntityManagerFactory("org.drools.persistence.jpa"));
        env.set(EnvironmentName.TRANSACTION_MANAGER, TransactionManagerServices.getTransactionManager());
        return env;
    }

    private KieSession createNewKieSession() {
        KieSession kieSession = kieServices.getStoreServices().newKieSession(getKieBase(), null, getEnv());
        PersistentDroolConfig.KIE_SESSION_ID = kieSession.getIdentifier();
        return kieSession;
    }

    private KieSession getPersistentKieSession() {
        return kieServices.getStoreServices().loadKieSession(KIE_SESSION_ID, getKieBase(), null, getEnv());
    }

    private void initDataSource() {
        PoolingDataSource ds = new PoolingDataSource();
        ds.setUniqueName("jdbc/BitronixJTADataSource");
        ds.setClassName("com.mysql.cj.jdbc.MysqlXADataSource");
        ds.setMaxPoolSize(3);
        ds.setAllowLocalTransactions(true);
        ds.getDriverProperties().put("user", "root");
        ds.getDriverProperties().put("password", "1234");
        ds.getDriverProperties().put("URL", "jdbc:mysql://localhost:3306/drool_demo");
        ds.init();
    }
}

更新

正如不同评论中所述，在进行这些更改后，出现了与用于生成实体SessionInfo的字段id值的SESSIONINFO_ID_SEQ序列相关的问题。

问题似乎与使用的 Hibernate 和 MySQL 的版本有关。

要解决该问题，需要对persistence.xml文件进行几处更改。

首先，应包括以下属性：

<property name="hibernate.id.new_generator_mappings" value="false" />

它经常用于 Drools 示例和测试用例。 请参阅这篇很棒的 Vlad Mihalcea 文章以获得深入的解释。

包含此配置属性会产生与所使用的 MySQL 方言相关的新问题。 应该改为：

<property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>

使用此配置，应用程序应该可以顺利运行。

Answer 2

您是否在容器中配置了 jndi 数据源？

<Resource name="jdbc/TestDB" auth="Container" type="javax.sql.DataSource"
    maxTotal="100" maxIdle="30" maxWaitMillis="10000"
    username="javauser" password="javadude" driverClassName="com.mysql.jdbc.Driver"
    url="jdbc:mysql://localhost:3306/javatest"/>

Tomcat jndi 数据源示例