MongoDB多数据源配置与切换的方法示例

spring:
  data:
    mongodb:
      primary:
        uri: mongodb://localhost:27017/primarydb
      secondary:
        uri: mongodb://localhost:27017/secondarydb

import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
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;

@Configuration
public class MongoConfig {

    @Primary
    @Bean(name = "primaryMongoTemplate")
    public MongoTemplate primaryMongoTemplate() {
        MongoClient mongoClient = MongoClients.create("mongodb://localhost:27017/primarydb");
        return new MongoTemplate(mongoClient, "primarydb");
    }

    @Bean(name = "secondaryMongoTemplate")
    public MongoTemplate secondaryMongoTemplate() {
        MongoClient mongoClient = MongoClients.create("mongodb://localhost:27017/secondarydb");
        return new MongoTemplate(mongoClient, "secondarydb");
    }
}

import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class DynamicDataSourceAspect {

    @Autowired
    private ApplicationContext applicationContext;

    @Around("@annotation(UseDataSource)")
    public Object switchDataSource(ProceedingJoinPoint joinPoint) throws Throwable {
        MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
        UseDataSource useDataSource = methodSignature.getMethod().getAnnotation(UseDataSource.class);
        MongoTemplate mongoTemplate = (MongoTemplate) applicationContext.getBean(useDataSource.value());

        try {
            MongoTemplateContextHolder.setMongoTemplate(mongoTemplate);
            return joinPoint.proceed();
        } finally {
            MongoTemplateContextHolder.clear();
        }
    }
}

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface UseDataSource {
    String value();
}

public class MongoTemplateContextHolder {

    private static final ThreadLocal<MongoTemplate> CONTEXT = new ThreadLocal<>();

    public static void setMongoTemplate(MongoTemplate mongoTemplate) {
        CONTEXT.set(mongoTemplate);
    }

    public static MongoTemplate getMongoTemplate() {
        return CONTEXT.get();
    }

    public static void clear() {
        CONTEXT.remove();
    }
}

@Service
public class MyService {

    @Autowired
    private MongoTemplate primaryMongoTemplate;

    @Autowired
    private MongoTemplate secondaryMongoTemplate;

    public void someMethod(boolean usePrimary) {
        MongoTemplate mongoTemplate = usePrimary ? primaryMongoTemplate : secondaryMongoTemplate;
        // 使用mongoTemplate进行操作
    }
}