整合Flowable-ui-modeler和MybatisPlus遇到的问题

整合Flowable-ui-modeler和MybatisPlus

启动出现报错：

file [F:\code_test\flowable-boot\target\classes\com\example\flowableboot\flowable\mapper\ProcessModelMapper.class] required a single bean, but 2 were found:
	- sqlSessionFactory: defined by method 'sqlSessionFactory' in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]
	- modelerSqlSessionFactory: defined by method 'modelerSqlSessionFactory' in class path resource [org/flowable/ui/modeler/conf/ModelerDatabaseConfiguration.class]


Action:

Consider marking one of the beans as @Primary, updating the consumer to accept multiple beans, or using @Qualifier to identify the bean that should be consumed

Disconnected from the target VM, address: '127.0.0.1:63899', transport: 'socket'

看flowable源码可以知道，flowable-ui-modeler在查询模型时，自己整合了mybatis，并且初始化了自己的sqlSessionFactory和 sqlSessionTemplate,如下

package org.flowable.ui.modeler.conf;

import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.ibatis.session.SqlSessionFactory;
import org.flowable.common.engine.api.FlowableException;
import org.flowable.ui.common.service.exception.InternalServerErrorException;
import org.flowable.ui.common.util.LiquibaseUtil;
import org.flowable.ui.modeler.properties.FlowableModelerAppProperties;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.io.support.ResourcePatternUtils;

import liquibase.Liquibase;
import liquibase.database.Database;
import liquibase.database.DatabaseConnection;
import liquibase.database.DatabaseFactory;
import liquibase.database.jvm.JdbcConnection;
import liquibase.exception.DatabaseException;
import liquibase.resource.ClassLoaderResourceAccessor;

@Configuration(proxyBeanMethods = false)
public class ModelerDatabaseConfiguration {

    private static final Logger LOGGER = LoggerFactory.getLogger(ModelerDatabaseConfiguration.class);

    protected static final String LIQUIBASE_CHANGELOG_PREFIX = "ACT_DE_";

    @Autowired
    protected FlowableModelerAppProperties modelerAppProperties;

    @Autowired
    protected ResourceLoader resourceLoader;

    protected static Properties databaseTypeMappings = getDefaultDatabaseTypeMappings();

    public static final String DATABASE_TYPE_H2 = "h2";
    public static final String DATABASE_TYPE_HSQL = "hsql";
    public static final String DATABASE_TYPE_MYSQL = "mysql";
    public static final String DATABASE_TYPE_ORACLE = "oracle";
    public static final String DATABASE_TYPE_POSTGRES = "postgres";
    public static final String DATABASE_TYPE_MSSQL = "mssql";
    public static final String DATABASE_TYPE_DB2 = "db2";

    public static Properties getDefaultDatabaseTypeMappings() {
        Properties databaseTypeMappings = new Properties();
        databaseTypeMappings.setProperty("H2", DATABASE_TYPE_H2);
        databaseTypeMappings.setProperty("HSQL Database Engine", DATABASE_TYPE_HSQL);
        databaseTypeMappings.setProperty("MySQL", DATABASE_TYPE_MYSQL);
        databaseTypeMappings.setProperty("MariaDB", DATABASE_TYPE_MYSQL);
        databaseTypeMappings.setProperty("Oracle", DATABASE_TYPE_ORACLE);
        databaseTypeMappings.setProperty("PostgreSQL", DATABASE_TYPE_POSTGRES);
        databaseTypeMappings.setProperty("Microsoft SQL Server", DATABASE_TYPE_MSSQL);
        databaseTypeMappings.setProperty(DATABASE_TYPE_DB2, DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/NT", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/NT64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2 UDP", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUX", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUX390", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUXX8664", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUXZ64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUXPPC64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/LINUXPPC64LE", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/400 SQL", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/6000", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2 UDB iSeries", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/AIX64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/HPUX", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/HP64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/SUN", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/SUN64", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/PTX", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2/2", DATABASE_TYPE_DB2);
        databaseTypeMappings.setProperty("DB2 UDB AS400", DATABASE_TYPE_DB2);
        return databaseTypeMappings;
    }

    @Bean
    @Qualifier("flowableModeler")
    public SqlSessionFactory modelerSqlSessionFactory(DataSource dataSource) {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSource);
        String databaseType = initDatabaseType(dataSource);
        if (databaseType == null) {
            throw new FlowableException("couldn't deduct database type");
        }

        try {
            Properties properties = new Properties();
            properties.put("prefix", modelerAppProperties.getDataSourcePrefix());
            properties.put("blobType", "BLOB");
            properties.put("boolValue", "TRUE");

            properties.load(this.getClass().getClassLoader().getResourceAsStream("org/flowable/db/properties/" + databaseType + ".properties"));

            sqlSessionFactoryBean.setConfigurationProperties(properties);
            sqlSessionFactoryBean
                    .setMapperLocations(ResourcePatternUtils.getResourcePatternResolver(resourceLoader).getResources("classpath:/META-INF/modeler-mybatis-mappings/*.xml"));
            sqlSessionFactoryBean.afterPropertiesSet();
            return sqlSessionFactoryBean.getObject();
        } catch (Exception e) {
            throw new FlowableException("Could not create sqlSessionFactory", e);
        }

    }

    @Bean(destroyMethod = "clearCache") // destroyMethod: see https://github.com/mybatis/old-google-code-issues/issues/778
    @Qualifier("flowableModeler")
    public SqlSessionTemplate modelerSqlSessionTemplate(@Qualifier("flowableModeler") SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    @Bean
    @Qualifier("flowableModeler")
    public Liquibase modelerLiquibase(DataSource dataSource) {
        LOGGER.info("Configuring Liquibase");

        try {
            return LiquibaseUtil.runInFlowableScope(() -> createAndUpdateLiquibase(dataSource));
        } catch (Exception e) {
            throw new InternalServerErrorException("Error creating liquibase database", e);
        }
    }

    protected Liquibase createAndUpdateLiquibase(DataSource dataSource) {
        Liquibase liquibase = null;
        try {
            DatabaseConnection connection = new JdbcConnection(dataSource.getConnection());
            Database database = DatabaseFactory.getInstance().findCorrectDatabaseImplementation(connection);
            database.setDatabaseChangeLogTableName(LIQUIBASE_CHANGELOG_PREFIX + database.getDatabaseChangeLogTableName());
            database.setDatabaseChangeLogLockTableName(LIQUIBASE_CHANGELOG_PREFIX + database.getDatabaseChangeLogLockTableName());

            liquibase = new Liquibase("META-INF/liquibase/flowable-modeler-app-db-changelog.xml", new ClassLoaderResourceAccessor(), database);
            liquibase.update("flowable");
            return liquibase;

        } catch (Exception e) {
            throw new InternalServerErrorException("Error creating liquibase database", e);
        } finally {
            closeDatabase(liquibase);
        }
    }

    protected String initDatabaseType(DataSource dataSource) {
        String databaseType = null;
        Connection connection = null;
        try {
            connection = dataSource.getConnection();
            DatabaseMetaData databaseMetaData = connection.getMetaData();
            String databaseProductName = databaseMetaData.getDatabaseProductName();
            LOGGER.info("database product name: '{}'", databaseProductName);
            databaseType = databaseTypeMappings.getProperty(databaseProductName);
            if (databaseType == null) {
                throw new FlowableException("couldn't deduct database type from database product name '" + databaseProductName + "'");
            }
            LOGGER.info("using database type: {}", databaseType);

        } catch (SQLException e) {
            LOGGER.error("Exception while initializing Database connection", e);
        } finally {
            try {
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                LOGGER.error("Exception while closing the Database connection", e);
            }
        }

        return databaseType;
    }

    private void closeDatabase(Liquibase liquibase) {
        if (liquibase != null) {
            Database database = liquibase.getDatabase();
            if (database != null) {
                try {
                    database.close();
                } catch (DatabaseException e) {
                    LOGGER.warn("Error closing database", e);
                }
            }
        }
    }

}

然后mybatis-plus也在自动配置类中启动初始化了sqlSessionFactory和 sqlSessionTemplate，如下

package com.baomidou.mybatisplus.autoconfigure;

import com.baomidou.mybatisplus.core.MybatisConfiguration;
import com.baomidou.mybatisplus.core.config.GlobalConfig;
import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
import com.baomidou.mybatisplus.core.incrementer.IKeyGenerator;
import com.baomidou.mybatisplus.core.incrementer.IdentifierGenerator;
import com.baomidou.mybatisplus.core.injector.ISqlInjector;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;
import java.util.Iterator;
import java.util.List;
import java.util.Optional;
import java.util.function.Consumer;
import java.util.stream.Stream;
import javax.sql.DataSource;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.mapping.DatabaseIdProvider;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.scripting.LanguageDriver;
import org.apache.ibatis.session.ExecutorType;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.type.TypeHandler;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.mapper.MapperFactoryBean;
import org.mybatis.spring.mapper.MapperScannerConfigurer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.ObjectProvider;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.boot.autoconfigure.AutoConfigurationPackages;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnSingleCandidate;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ObjectUtils;
import org.springframework.util.StringUtils;

@Configuration
@ConditionalOnClass({SqlSessionFactory.class, SqlSessionFactoryBean.class})
@ConditionalOnSingleCandidate(DataSource.class)
@EnableConfigurationProperties({MybatisPlusProperties.class})
@AutoConfigureAfter({DataSourceAutoConfiguration.class, MybatisPlusLanguageDriverAutoConfiguration.class})
public class MybatisPlusAutoConfiguration implements InitializingBean {
    private static final Logger logger = LoggerFactory.getLogger(MybatisPlusAutoConfiguration.class);
    private final MybatisPlusProperties properties;
    private final Interceptor[] interceptors;
    private final TypeHandler[] typeHandlers;
    private final LanguageDriver[] languageDrivers;
    private final ResourceLoader resourceLoader;
    private final DatabaseIdProvider databaseIdProvider;
    private final List<ConfigurationCustomizer> configurationCustomizers;
    private final List<MybatisPlusPropertiesCustomizer> mybatisPlusPropertiesCustomizers;
    private final ApplicationContext applicationContext;

    public MybatisPlusAutoConfiguration(MybatisPlusProperties properties, ObjectProvider<Interceptor[]> interceptorsProvider, ObjectProvider<TypeHandler[]> typeHandlersProvider, ObjectProvider<LanguageDriver[]> languageDriversProvider, ResourceLoader resourceLoader, ObjectProvider<DatabaseIdProvider> databaseIdProvider, ObjectProvider<List<ConfigurationCustomizer>> configurationCustomizersProvider, ObjectProvider<List<MybatisPlusPropertiesCustomizer>> mybatisPlusPropertiesCustomizerProvider, ApplicationContext applicationContext) {
        this.properties = properties;
        this.interceptors = (Interceptor[])interceptorsProvider.getIfAvailable();
        this.typeHandlers = (TypeHandler[])typeHandlersProvider.getIfAvailable();
        this.languageDrivers = (LanguageDriver[])languageDriversProvider.getIfAvailable();
        this.resourceLoader = resourceLoader;
        this.databaseIdProvider = (DatabaseIdProvider)databaseIdProvider.getIfAvailable();
        this.configurationCustomizers = (List)configurationCustomizersProvider.getIfAvailable();
        this.mybatisPlusPropertiesCustomizers = (List)mybatisPlusPropertiesCustomizerProvider.getIfAvailable();
        this.applicationContext = applicationContext;
    }

    public void afterPropertiesSet() {
        if (!CollectionUtils.isEmpty(this.mybatisPlusPropertiesCustomizers)) {
            this.mybatisPlusPropertiesCustomizers.forEach((i) -> {
                i.customize(this.properties);
            });
        }

        this.checkConfigFileExists();
    }

    private void checkConfigFileExists() {
        if (this.properties.isCheckConfigLocation() && StringUtils.hasText(this.properties.getConfigLocation())) {
            Resource resource = this.resourceLoader.getResource(this.properties.getConfigLocation());
            Assert.state(resource.exists(), "Cannot find config location: " + resource + " (please add config file or check your Mybatis configuration)");
        }

    }

    @Bean
    @ConditionalOnMissingBean
    public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
        MybatisSqlSessionFactoryBean factory = new MybatisSqlSessionFactoryBean();
        factory.setDataSource(dataSource);
        factory.setVfs(SpringBootVFS.class);
        if (StringUtils.hasText(this.properties.getConfigLocation())) {
            factory.setConfigLocation(this.resourceLoader.getResource(this.properties.getConfigLocation()));
        }

        this.applyConfiguration(factory);
        if (this.properties.getConfigurationProperties() != null) {
            factory.setConfigurationProperties(this.properties.getConfigurationProperties());
        }

        if (!ObjectUtils.isEmpty(this.interceptors)) {
            factory.setPlugins(this.interceptors);
        }

        if (this.databaseIdProvider != null) {
            factory.setDatabaseIdProvider(this.databaseIdProvider);
        }

        if (StringUtils.hasLength(this.properties.getTypeAliasesPackage())) {
            factory.setTypeAliasesPackage(this.properties.getTypeAliasesPackage());
        }

        if (this.properties.getTypeAliasesSuperType() != null) {
            factory.setTypeAliasesSuperType(this.properties.getTypeAliasesSuperType());
        }

        if (StringUtils.hasLength(this.properties.getTypeHandlersPackage())) {
            factory.setTypeHandlersPackage(this.properties.getTypeHandlersPackage());
        }

        if (!ObjectUtils.isEmpty(this.typeHandlers)) {
            factory.setTypeHandlers(this.typeHandlers);
        }

        Resource[] mapperLocations = this.properties.resolveMapperLocations();
        if (!ObjectUtils.isEmpty(mapperLocations)) {
            factory.setMapperLocations(mapperLocations);
        }

        Class<? extends LanguageDriver> defaultLanguageDriver = this.properties.getDefaultScriptingLanguageDriver();
        if (!ObjectUtils.isEmpty(this.languageDrivers)) {
            factory.setScriptingLanguageDrivers(this.languageDrivers);
        }

        Optional.ofNullable(defaultLanguageDriver).ifPresent(factory::setDefaultScriptingLanguageDriver);
        if (StringUtils.hasLength(this.properties.getTypeEnumsPackage())) {
            factory.setTypeEnumsPackage(this.properties.getTypeEnumsPackage());
        }

        GlobalConfig globalConfig = this.properties.getGlobalConfig();
        this.getBeanThen(MetaObjectHandler.class, globalConfig::setMetaObjectHandler);
        this.getBeanThen(IKeyGenerator.class, (i) -> {
            globalConfig.getDbConfig().setKeyGenerator(i);
        });
        this.getBeanThen(ISqlInjector.class, globalConfig::setSqlInjector);
        this.getBeanThen(IdentifierGenerator.class, globalConfig::setIdentifierGenerator);
        factory.setGlobalConfig(globalConfig);
        return factory.getObject();
    }

    private <T> void getBeanThen(Class<T> clazz, Consumer<T> consumer) {
        if (this.applicationContext.getBeanNamesForType(clazz, false, false).length > 0) {
            consumer.accept(this.applicationContext.getBean(clazz));
        }

    }

    private void applyConfiguration(MybatisSqlSessionFactoryBean factory) {
        MybatisConfiguration configuration = this.properties.getConfiguration();
        if (configuration == null && !StringUtils.hasText(this.properties.getConfigLocation())) {
            configuration = new MybatisConfiguration();
        }

        if (configuration != null && !CollectionUtils.isEmpty(this.configurationCustomizers)) {
            Iterator var3 = this.configurationCustomizers.iterator();

            while(var3.hasNext()) {
                ConfigurationCustomizer customizer = (ConfigurationCustomizer)var3.next();
                customizer.customize(configuration);
            }
        }

        factory.setConfiguration(configuration);
    }

    @Bean
    @ConditionalOnMissingBean
    public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
        ExecutorType executorType = this.properties.getExecutorType();
        return executorType != null ? new SqlSessionTemplate(sqlSessionFactory, executorType) : new SqlSessionTemplate(sqlSessionFactory);
    }

    @Configuration
    @Import({MybatisPlusAutoConfiguration.AutoConfiguredMapperScannerRegistrar.class})
    @ConditionalOnMissingBean({MapperFactoryBean.class, MapperScannerConfigurer.class})
    public static class MapperScannerRegistrarNotFoundConfiguration implements InitializingBean {
        public MapperScannerRegistrarNotFoundConfiguration() {
        }

        public void afterPropertiesSet() {
            MybatisPlusAutoConfiguration.logger.debug("Not found configuration for registering mapper bean using @MapperScan, MapperFactoryBean and MapperScannerConfigurer.");
        }
    }

    public static class AutoConfiguredMapperScannerRegistrar implements BeanFactoryAware, ImportBeanDefinitionRegistrar {
        private BeanFactory beanFactory;

        public AutoConfiguredMapperScannerRegistrar() {
        }

        public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
            if (!AutoConfigurationPackages.has(this.beanFactory)) {
                MybatisPlusAutoConfiguration.logger.debug("Could not determine auto-configuration package, automatic mapper scanning disabled.");
            } else {
                MybatisPlusAutoConfiguration.logger.debug("Searching for mappers annotated with @Mapper");
                List<String> packages = AutoConfigurationPackages.get(this.beanFactory);
                if (MybatisPlusAutoConfiguration.logger.isDebugEnabled()) {
                    packages.forEach((pkg) -> {
                        MybatisPlusAutoConfiguration.logger.debug("Using auto-configuration base package '{}'", pkg);
                    });
                }

                BeanDefinitionBuilder builder = BeanDefinitionBuilder.genericBeanDefinition(MapperScannerConfigurer.class);
                builder.addPropertyValue("processPropertyPlaceHolders", true);
                builder.addPropertyValue("annotationClass", Mapper.class);
                builder.addPropertyValue("basePackage", StringUtils.collectionToCommaDelimitedString(packages));
                BeanWrapper beanWrapper = new BeanWrapperImpl(MapperScannerConfigurer.class);
                Stream.of(beanWrapper.getPropertyDescriptors()).filter((x) -> {
                    return x.getName().equals("lazyInitialization");
                }).findAny().ifPresent((x) -> {
                    builder.addPropertyValue("lazyInitialization", "${mybatis.lazy-initialization:false}");
                });
                registry.registerBeanDefinition(MapperScannerConfigurer.class.getName(), builder.getBeanDefinition());
            }
        }

        public void setBeanFactory(BeanFactory beanFactory) {
            this.beanFactory = beanFactory;
        }
    }
}

不过flowable还算不错，都给sqlSessionFactory和 sqlSessionTemplate起了别名，看报错信息也知道需要给你自己定义的mapper指定一个sqlSessionFactory，所以只需要在扫描mapper时指定mybatis-plus初始化的sqlSessionFactory和 sqlSessionTemplate即可，而不需要重写配置啥的。如下：

@SpringBootApplication
@MapperScan(basePackages = {"com.example.flowableboot.flowable.mapper"}, sqlSessionFactoryRef = "sqlSessionFactory", sqlSessionTemplateRef = "sqlSessionTemplate")
public class FlowableBootApplication {

    public static void main(String[] args) {
        SpringApplication.run(FlowableBootApplication.class, args);
    }

}

其实自己用Mybatis写多数据源配置也可以这么弄，不同的包指定不同的sqlSessionFactory和 sqlSessionTemplate