mongodb實現多數據源

       最近在開發過程中遇到一個需求，想要實現該需求需要把一個mongodb庫里面的表&數據復制到另一個mongodb庫。首先需要做的一件事就是配置多數據源，由於項目采用SpringBoot，所以配置多數據源也是在這個框架基礎上的。話不多說，直接上代碼

首先pom.xml需要引入如下配置

<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-configuration-processor</artifactId>
   <optional>true</optional>
</dependency>
<dependency>
   <groupId>org.springframework.boot</groupId>
   <artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>

分別定義三個類AbstractMongoConfig、PrimaryMongoConfig、SecondMongoConfig

import com.mongodb.MongoClientURI;
import org.springframework.data.mongodb.MongoDbFactory;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.SimpleMongoDbFactory;

/**
 * 描述
 *
 * @author mczhou2 2020/3/2010:50
 */
public abstract  class AbstractMongoConfig {
    //連接MongoDB地址
    private String uri;
    /**
     * 獲取mongoDBTemplate對象
     */
    public abstract MongoTemplate getMongoTemplate() throws Exception;
    /**
     * 創建mongoDb工廠
     */
    public MongoDbFactory mongoDbFactory() throws Exception {
        MongoClientURI mongoclienturi = new MongoClientURI(uri);
        return new SimpleMongoDbFactory(mongoclienturi);
    }
    public String getUri() {
        return uri;
    }

    public void setUri(String uri) {
        this.uri = uri;
    }
}

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;

/**
 * 描述
 *
 * @author mczhou2 2020/3/20 10:51
 */
@Configuration
@ConfigurationProperties(prefix = "spring.data.mongodb.primary")
public class PrimaryMongoConfig extends AbstractMongoConfig{
    @Override
    @Primary
    @Bean(name = "primaryMongoTemplate")
    public MongoTemplate getMongoTemplate() throws Exception {
        return new MongoTemplate((mongoDbFactory()));
    }
}

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;

/**
 * 描述
 *
 * @author mczhou2 2020/3/2010:51
 */
@Configuration
@ConfigurationProperties(prefix = "spring.data.mongodb.second")
public class SecondaryMongoConfig extends AbstractMongoConfig{

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

接下來啟動類的注解需要屏蔽之前的類，否在項目啟動報錯

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.data.mongo.MongoDataAutoConfiguration;
import org.springframework.boot.autoconfigure.mongo.MongoAutoConfiguration;

@SpringBootApplication(exclude = {MongoAutoConfiguration.class, MongoDataAutoConfiguration.class})
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class,args);
    }
}

至此，mongodb多數據源就配置好了。這時候大家也許會問，前期准備工作好了，到底怎么用？你確定你想知道，那下回來我手把手教你。