如何在spring boot中使用多个mongodb数据库？

Question

我使用spring boot来操作mongodb，在我的application.properties中是spring.data.mongodb.uri=mongodb://username:password@hostIp:27017/database1 我添加 jar 是 spring-boot-starter-data-mongodb，但是现在我的mongodb里面有两个数据库，我的spring boot怎么添加另外一个数据库，用不同的数据库怎么区分？

Answer 1

是的，您可以在单个 spring-boot 应用程序中配置 2 个数据库。 您必须在单个 application.yml 文件中添加两个数据库属性。

#application.yml
        spring:
          data:
            mongodb:
              database: database_one
              uri: mongodb://root:root@172.0.0.1:27017/database_one
    # username : root, Password : root

        secondary:
          mongodb:
            database: database_two
            uri: mongodb://root:password@172.0.0.1:27017/database_two
    # username : root, Password : password

然后你必须为spring添加两个数据库配置文件，并在每个文件中读取这两个属性。对于第一个数据库配置文件，只需为主数据库属性添加 @Primary 注释。 您可以根据需要将这两个文件合并为一个。

@Configuration
public class DatabaseConfiguration {

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

    @Value("${spring.data.mongodb.uri}")
    private String mongoUri;

    @Value("${spring.data.mongodb.database}")
    private String mongoDbName;

    @Primary
    @Bean
    public MongoTemplate mongoTemplate() {    
        LOGGER.debug(" Instantiating MongoDbFactory ");
        SimpleMongoDbFactory mongoDbFactory = new SimpleMongoDbFactory(mongoClient(), mongoDbName);
            return new MongoTemplate(mongoDbFactory);
        }

    @Primary
    @Bean
    public MongoClient mongoClient() {
        return new MongoClient(mongoClientURI());
    }

    @Primary
    @Bean
    public MongoClientURI mongoClientURI() {
        LOGGER.debug(" creating connection with mongodb with uri [{}] ", mongoUri);
        return new MongoClientURI(mongoUri);
    }

}


# Second database configuration file.

@Configuration
public class SecondaryDatabaseConfiguration {

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

    @Value("${secondary.mongodb.uri}")
    private String mongoUri;

    @Value("${secondary.mongodb.database}")
    private String mongoDbName ;

    @Bean(name = "mongoTemplateSecond")
    public MongoTemplate mongoTemplateSecondary() {
        LOGGER.debug(" Instantiating MongoDbFactory ");
        SimpleMongoDbFactory mongoDbFactory = new SimpleMongoDbFactory(mongoClientSecondary(), mongoDbName);
        return new MongoTemplate(mongoDbFactory);
    }

    @Bean
    public MongoClient mongoClientSecondary() {
        return new MongoClient(mongoClientURISecondary());
    }

    @Bean
    public MongoClientURI mongoClientURISecondary() {
        LOGGER.debug(" creating connection with mongodb with uri [{}] ", mongoUri);
        return new MongoClientURI(mongoUri);
    }
}

然后在你的实现类中使用@Qualifier注解，如果你想从辅助数据库中获取，则传递bean名称，而对于主数据库，你可以直接Autowire。
@Qualifier 注解用于区分相同类型的bean。

    @Component
public class RepositoryImpl{

    @Qualifier(value = "mongoTemplateSecond")
    @Autowired
    MongoTemplate mongoTemplateSecond;   // for secondary database


    @Autowired
    private MongoTemplate mongoTemplate; // for primary database 


    public List<BasicDBObject> findRecordsInSecondary(Query query){
        List<BasicDBObject> basicDBObjects = mongoTemplateSecond.find(query, BasicDBObject.class, YOUR_COLLECTION_NAME);
        return basicDBObjects;
    }


    public List<BasicDBObject> findRecordsInPrimary(Query query){
        List<BasicDBObject> basicDBObjects = mongoTemplate.find(query, BasicDBObject.class, YOUR_COLLECTION_NAME);
        return basicDBObjects;
    }
}