springcloud模块化开发的代码例子

下面是一个简单的基于Spring Cloud的模块化开发的代码示例：

1. 创建一个父项目，pom.xml中添加如下依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
    </dependency>
</dependencies>

2. 创建一个Eureka Server模块，pom.xml中添加如下依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
    </dependency>
</dependencies>

3. 创建一个API Gateway模块，pom.xml中添加如下依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-gateway</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
</dependencies>

4. 创建一个Service A模块，pom.xml中添加如下依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
</dependencies>

5. 创建一个Service B模块，pom.xml中添加如下依赖

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
    </dependency>
</dependencies>

6. 在application.yml中配置Eureka Server地址和各个模块的端口信息

# Eureka Server 配置
server:
  port: 8761

eureka:
  instance:
    hostname: localhost
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/

# API Gateway 配置
spring:
  cloud:
    gateway:
      routes:
        - id: service-a
          uri: lb://service-a
          predicates:
            - Path=/service-a/**
        - id: service-b
          uri: lb://service-b
          predicates:
            - Path=/service-b/**

# Service A 配置
server:
  port: 8081

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

# Service B 配置
server:
  port: 8082

eureka:
  client:
    service-url:
      defaultZone: http://localhost:8761/eureka/

通过以上配置，我们可以实现API Gateway作为服务的统一入口，并通过Eureka Server进行服务发现和负载均衡。