Golang 마이크로서비스 개발은 어떤 실용적인 애플리케이션을 달성할 수 있나요?

package main

import (
    "net/http"
    "log"
)

func main() {
    http.HandleFunc("/", helloHandler)
    log.Fatal(http.ListenAndServe(":8080", nil))
}

func helloHandler(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("Hello, World!"))
}

package main

import (
    "log"
    "github.com/Shopify/sarama"
    "os"
    "os/signal"
    "syscall"
)

func main() {
    config := sarama.NewConfig()
    config.Consumer.Return.Errors = true

    consumer, err := sarama.NewConsumer([]string{"localhost:9092"}, config)
    if err != nil {
        log.Fatal(err)
    }
    defer consumer.Close()

    partitionConsumer, err := consumer.ConsumePartition("my_topic", 0, sarama.OffsetNewest)
    if err != nil {
        log.Fatal(err)
    }
    defer partitionConsumer.Close()

    signals := make(chan os.Signal, 1)
    signal.Notify(signals, syscall.SIGINT, syscall.SIGTERM)

    for {
        select {
        case msg := <-partitionConsumer.Messages():
            log.Printf("Received message: %s
", string(msg.Value))
        case err := <-partitionConsumer.Errors():
            log.Printf("Error: %s
", err.Error())
        case <-signals:
            return
        }
    }
}

package main

import (
    "log"
    "math/rand"
    "time"
)

func main() {
    tasks := []int{1, 2, 3, 4, 5}
    results := make(chan int)

    for _, task := range tasks {
        go calculate(task, results)
    }

    for i := 0; i < len(tasks); i++ {
        result := <-results
        log.Printf("Result: %d
", result)
    }
}

func calculate(task int, results chan<- int) {
    time.Sleep(time.Duration(rand.Intn(5)) * time.Second) // 模拟计算耗时
    result := task * 2
    results <- result
}