SpringBoot如何配置MongoDB多数据源

SpringBoot如何配置MongoDB多数据源？针对这个问题，这篇文章详细介绍了相对应的分析和解答，希望可以帮助更多想解决这个问题的小伙伴找到更简单易行的方法。

1、项目构建

添加 pom 文件

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

2、在 application.properties 中添加配置

##start mongodb for basic
#----------------------------------------------
basic.spring.data.mongodb.host=localhost
basic.spring.data.mongodb.port=27016
basic.spring.data.mongodb.username=auto_compute
basic.spring.data.mongodb.password=vqOqSZRs
basic.spring.data.mongodb.database=auto_compute
#----------------------------------------------
##end mongodb for spirit
##start mongodb for auth
#----------------------------------------------
auth.spring.data.mongodb.host=localhost
auth.spring.data.mongodb.port=27016
auth.spring.data.mongodb.username=datacenter
auth.spring.data.mongodb.password=Bds6NadsfafGlV
auth.spring.data.mongodb.database=datacenter
#----------------------------------------------
##end mongodb for spirit

3、配置相应的数据源

采用 mongoTemplate 进行 mongo 的相关操作，写一个基础的抽象类

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import lombok.Getter;
import lombok.Setter;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.SimpleMongoDbFactory;

import java.util.ArrayList;
import java.util.List;

@Getter
@Setter
public abstract class AbstractMongoConfigure {

  private String host;
  private int port;
  private String username;
  private String password;
  private String database;


  public MongoDbFactory mongoDbFactory() throws Exception {
    /*// 无认证的初始化方法
    return new SimpleMongoDbFactory(new MongoClient(host, port), database);*/

    //有认证的初始化方法
    ServerAddress serverAddress = new ServerAddress(host, port);
    List<MongoCredential> mongoCredentialList = new ArrayList<>();
    MongoCredential mongoCredential = MongoCredential.createCredential(username, database, password.toCharArray());
    mongoCredentialList.add(mongoCredential);
    return new SimpleMongoDbFactory(new MongoClient(serverAddress, mongoCredentialList), database);
  }

  abstract public MongoTemplate getMongoTemplate() throws Exception;
}

数据源加载需要继承 AbstractMongoConfigure 抽象类，有多少个数据源就需要新建多少个数据源加载类

3.1、第一个数据源

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;

@Configuration
@EnableMongoRepositories(basePackages = {"com.tcl.dc.autodata.dao.base"}, mongoTemplateRef = "mongoTemplate")
@ConfigurationProperties(prefix = "basic.spring.data.mongodb")
public class BasicMongoConfig extends AbstractMongoConfigure {

  @Primary
  @Bean(name = "mongoTemplate")
  @Override
  public MongoTemplate getMongoTemplate() throws Exception {
    return new MongoTemplate(mongoDbFactory());
  }
}

其中 basePackages 的值用于相应的基础包，prefix 为 application.properties 中的配置值

3.2、第二个数据源

import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;

@Configuration
@EnableMongoRepositories(basePackages = {"com.tcl.dc.autodata.dao.auth"}, mongoTemplateRef = "authMongoTemplate")
@ConfigurationProperties(prefix = "auth.spring.data.mongodb")
public class AuthMongoConfig extends AbstractMongoConfigure {

  @Bean(name = "authMongoTemplate")
  @Override
  public MongoTemplate getMongoTemplate() throws Exception {
    return new MongoTemplate(mongoDbFactory());
  }
}

4、注意

1、多个数据源中有一个 bean 需要设置为 mongoTemplate ，且必须添加 @Primary 注解，否则 WebMvcConfigurationSupport.class 等会报错找不到 mongoTemplate

2、Spring Boot 会自动注入 mongoTemplate ，与我们配置的多个数据源有冲突。为了防止默认注入，需要排除自动注入的类。在 Spring Boot 的启动类 Applocation.java 添加排除类注解

@SpringBootApplication(exclude = {
    MongoAutoConfiguration.class,
    MongoDataAutoConfiguration.class})

5、使用多个数据源

使用时，直接对应注入即可

@Autowired
@Qualifier(value = "mongoTemplate")
MongoTemplate mongoTemplate;

@Autowired
@Qualifier(value = "authMongoTemplate")
MongoTemplate authMongoTemplate;

6、可能遇到的问题

1、'com.mongodb.MongoClient' that could not be found

详细报错如下:

***************************
APPLICATION FAILED TO START
***************************

Description:

Parameter 0 of method mongoDbFactory in org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration required a bean of type 'com.mongodb.MongoClient' that could not be found.
    - Bean method 'mongo' not loaded because auto-configuration 'MongoAutoConfiguration' was excluded

Action:

Consider revisiting the conditions above or defining a bean of type 'com.mongodb.MongoClient' in your configuration.

原因：重写了 MongoClient 等之后导致原来的自动注入缺少 bean

解决方式：主要是看哪个自动注入的类在引用默认的 MongoClient ，把它排除出去即可，例如:

@SpringBootApplication(exclude = {
    MongoAutoConfiguration.class,
    MongoDataAutoConfiguration.class})

2、more than one ‘primary' bean found among candidates

详细报错如下:

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'sampleController': Unsatisfied dependency expressed through field 'mongoTemplate'; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'org.springframework.data.mongodb.core.MongoTemplate' available: more than one 'primary' bean found among candidates: [logMongoTemplate, userMongoTemplate, mongoTemplate]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:866) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:314) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
    at com.biologic.Applocation.main(Applocation.java:18) [classes/:na]
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'org.springframework.data.mongodb.core.MongoTemplate' available: more than one 'primary' bean found among candidates: [logMongoTemplate, userMongoTemplate, mongoTemplate]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.determinePrimaryCandidate(DefaultListableBeanFactory.java:1365) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.determineAutowireCandidate(DefaultListableBeanFactory.java:1326) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1113) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]

原因：Spring Boot 会自动注入一个默认的 mongoTemplate 或者设置了多个 @Primary 数据源

解决方式：排除 Spring Boot 自动注入的类，自动重写的 mongoTemplate 需要且只能设置一个为@Primary

关于SpringBoot如何配置MongoDB多数据源问题的解答就分享到这里了，希望以上内容可以对大家有一定的帮助，如果你还有很多疑惑没有解开，可以关注亿速云行业资讯频道了解更多相关知识。