GolangRPC多服务通信实战教程

// common/types.go
package common

type User struct {
    ID   int
    Name string
}

type Order struct {
    ID       int
    UserID   int
    Product  string
}

// user_service/server.go
package main

import (
    "common"
    "log"
    "net"
    "net/rpc"
)

type UserService struct{}

func (s *UserService) GetUser(uid int, user *common.User) error {
    // 模拟数据库查找
    userData := map[int]common.User{
        1: {ID: 1, Name: "Alice"},
        2: {ID: 2, Name: "Bob"},
    }
    *user = userData[uid]
    return nil
}

func main() {
    rpc.Register(new(UserService))
    listener, err := net.Listen("tcp", ":8081")
    if err != nil {
        log.Fatal("Listen error:", err)
    }
    defer listener.Close()
    log.Println("UserService 启动在 :8081")
    for {
        conn, _ := listener.Accept()
        go rpc.ServeConn(conn)
    }
}

// order_service/server.go
package main

import (
    "common"
    "log"
    "net"
    "net/rpc"
)

type OrderService struct{}

func (s *OrderService) GetOrder(oid int, reply *common.Order) error {
    // 模拟订单数据
    orderData := map[int]common.Order{
        101: {ID: 101, UserID: 1, Product: "Laptop"},
        102: {ID: 102, UserID: 2, Product: "Phone"},
    }
    *reply = orderData[oid]

    // 调用 UserService 获取用户信息
    client, err := rpc.Dial("tcp", "127.0.0.1:8081")
    if err != nil {
        log.Printf("无法连接 UserService: %v", err)
        return nil
    }
    defer client.Close()

    var user common.User
    err = client.Call("UserService.GetUser", reply.UserID, &user)
    if err != nil {
        log.Printf("调用 GetUser 失败: %v", err)
    } else {
        log.Printf("订单 %d 关联用户: %s", reply.ID, user.Name)
    }

    return nil
}

func main() {
    rpc.Register(new(OrderService))
    listener, err := net.Listen("tcp", ":8082")
    if err != nil {
        log.Fatal("Listen error:", err)
    }
    defer listener.Close()
    log.Println("OrderService 启动在 :8082")
    for {
        conn, _ := listener.Accept()
        go rpc.ServeConn(conn)
    }
}

// client/main.go
package main

import (
    "common"
    "log"
    "net/rpc"
)

func main() {
    client, err := rpc.Dial("tcp", "127.0.0.1:8082")
    if err != nil {
        log.Fatal("Dial error:", err)
    }
    defer client.Close()

    var order common.Order
    err = client.Call("OrderService.GetOrder", 101, &order)
    if err != nil {
        log.Fatal("Call error:", err)
    }

    log.Printf("获取订单: %+v", order)
}