如何在Spring应用中连接多个Couchbase集群并访问对应存储桶

1. 引入核心依赖 #

首先确保项目中引入Spring Data Couchbase的官方启动器，Maven依赖示例如下：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-couchbase</artifactId>
    <version>对应Spring Boot版本的稳定版即可</version>
</dependency>

2. 配置文件添加多集群参数 #

在application.yml或application.properties中分别配置两个集群的连接信息，示例如下：

# cluster1集群配置
couchbase.cluster1.connection-string: couchbase://cluster1的节点地址
couchbase.cluster1.username: cluster1的用户名
couchbase.cluster1.password: cluster1的密码
couchbase.cluster1.bucket-name: bucket1

# cluster2集群配置
couchbase.cluster2.connection-string: couchbase://cluster2的节点地址
couchbase.cluster2.username: cluster2的用户名
couchbase.cluster2.password: cluster2的密码
couchbase.cluster2.bucket-name: bucket2

3. 编写多集群配置类 #

Spring Data Couchbase默认的自动配置仅支持单集群，需要手动注册两个集群的独立Bean，并且通过包扫描隔离不同集群的Repository。

cluster1专属配置类 #

import com.couchbase.client.java.Cluster;
import com.couchbase.client.java.Bucket;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.couchbase.core.CouchbaseTemplate;
import org.springframework.data.couchbase.repository.config.EnableCouchbaseRepositories;

@Configuration
@EnableCouchbaseRepositories(
        basePackages = "com.yourproject.repository.cluster1",
        couchbaseTemplateRef = "cluster1CouchbaseTemplate"
)
public class Cluster1CouchbaseConfig {

    @Value("${couchbase.cluster1.connection-string}")
    private String cluster1ConnStr;
    @Value("${couchbase.cluster1.username}")
    private String cluster1Username;
    @Value("${couchbase.cluster1.password}")
    private String cluster1Password;
    @Value("${couchbase.cluster1.bucket-name}")
    private String cluster1BucketName;

    // 给cluster1的Bean加@Primary避免同类型Bean注入冲突
    @Primary
    @Bean("cluster1Cluster")
    public Cluster cluster1Cluster() {
        return Cluster.connect(cluster1ConnStr, cluster1Username, cluster1Password);
    }

    @Primary
    @Bean("cluster1Bucket")
    public Bucket cluster1Bucket() {
        return cluster1Cluster().bucket(cluster1BucketName);
    }

    @Primary
    @Bean("cluster1CouchbaseTemplate")
    public CouchbaseTemplate cluster1CouchbaseTemplate() {
        return new CouchbaseTemplate(cluster1Cluster(), cluster1Bucket());
    }
}

cluster2专属配置类 #

import com.couchbase.client.java.Cluster;
import com.couchbase.client.java.Bucket;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.couchbase.core.CouchbaseTemplate;
import org.springframework.data.couchbase.repository.config.EnableCouchbaseRepositories;

@Configuration
@EnableCouchbaseRepositories(
        basePackages = "com.yourproject.repository.cluster2",
        couchbaseTemplateRef = "cluster2CouchbaseTemplate"
)
public class Cluster2CouchbaseConfig {

    @Value("${couchbase.cluster2.connection-string}")
    private String cluster2ConnStr;
    @Value("${couchbase.cluster2.username}")
    private String cluster2Username;
    @Value("${couchbase.cluster2.password}")
    private String cluster2Password;
    @Value("${couchbase.cluster2.bucket-name}")
    private String cluster2BucketName;

    @Bean("cluster2Cluster")
    public Cluster cluster2Cluster() {
        return Cluster.connect(cluster2ConnStr, cluster2Username, cluster2Password);
    }

    @Bean("cluster2Bucket")
    public Bucket cluster2Bucket() {
        return cluster2Cluster().bucket(cluster2BucketName);
    }

    @Bean("cluster2CouchbaseTemplate")
    public CouchbaseTemplate cluster2CouchbaseTemplate() {
        return new CouchbaseTemplate(cluster2Cluster(), cluster2Bucket());
    }
}

4. 分包创建Repository接口 #

• 操作bucket1的Repository放在com.yourproject.repository.cluster1包下，自动绑定cluster1集群
• 操作bucket2的Repository放在com.yourproject.repository.cluster2包下，自动绑定cluster2集群
  示例：

// cluster1包下的Repository，操作bucket1
package com.yourproject.repository.cluster1;
import org.springframework.data.couchbase.repository.CouchbaseRepository;
import com.yourproject.entity.User;

public interface UserRepository extends CouchbaseRepository<User, String> {
}

5. 其他使用说明 #

如果不需要使用Repository接口，也可以直接在业务类中通过@Qualifier指定注入对应集群的Bucket或CouchbaseTemplate直接操作：

@Service
public class DemoService {
    // 注入cluster1的bucket
    @Autowired
    @Qualifier("cluster1Bucket")
    private Bucket bucket1;

    // 注入cluster2的template
    @Autowired
    @Qualifier("cluster2CouchbaseTemplate")
    private CouchbaseTemplate cluster2Template;
}

内容的提问来源于stack exchange，提问作者Guru Charan