使用Golang微服务开发可以实现哪些创新功能？

FROM golang:latest

WORKDIR /go/src/myapp
COPY . .

RUN go build -o myapp main.go

EXPOSE 8080

CMD ["./myapp"]

package main

import (
    "fmt"
    "net/http"
    "sync"
)

func main() {
    var wg sync.WaitGroup

    // 创建一个HTTP请求处理函数
    handler := func(w http.ResponseWriter, r *http.Request) {
        wg.Add(1)
        go func() {
            defer wg.Done()
            // 处理请求的业务逻辑
            // ...
            fmt.Fprintf(w, "Hello, World!")
        }()
    }

    // 创建一个HTTP服务器
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)

    wg.Wait()
}

package main

import (
    "fmt"

    "github.com/streadway/amqp"
)

func main() {
    // 连接到消息队列服务器
    conn, err := amqp.Dial("amqp://guest:guest@localhost:5672/")
    if err != nil {
        fmt.Println("Failed to connect to RabbitMQ:", err)
        return
    }
    defer conn.Close()

    // 打开一个通道
    ch, err := conn.Channel()
    if err != nil {
        fmt.Println("Failed to open a channel:", err)
        return
    }
    defer ch.Close()

    // 声明一个队列
    q, err := ch.QueueDeclare(
        "hello", // 队列名称
        false,   // 持久化
        false,   // 自动删除
        false,   // 独占队列
        false,   // No-wait
        nil,     // 参数
    )
    if err != nil {
        fmt.Println("Failed to declare a queue:", err)
        return
    }

    // 发送一条消息
    err = ch.Publish(
        "",     // 交换机名称
        q.Name, // 队列名称
        false,  // 立即发送处理
        false,  // 不需要等待确认
        amqp.Publishing{
            ContentType: "text/plain",
            Body:        []byte("Hello, World!"),
        })
    if err != nil {
        fmt.Println("Failed to publish a message:", err)
        return
    }

    fmt.Println("Message sent successfully!")
}

package main

import (
    "fmt"
    "log"
    "net/http"
    "os"

    "github.com/prometheus/client_golang/prometheus"
    "github.com/prometheus/client_golang/prometheus/promhttp"
)

func main() {
    // 创建一个新的计数器指标
    counter := prometheus.NewCounter(prometheus.CounterOpts{
        Name: "myapp_requests_total",
        Help: "The total number of requests to the myapp service.",
    })

    // 将指标注册到默认的注册表中
    prometheus.MustRegister(counter)

    // 增加计数器的值
    counter.Inc()

    // 开启一个HTTP服务器，用于暴露指标接口
    http.Handle("/metrics", promhttp.Handler())
    addr := fmt.Sprintf(":%s", os.Getenv("PORT"))
    log.Fatal(http.ListenAndServe(addr, nil))
}