http-handler.go

package main

import (
    "log"
    "net/http"
    "strconv"
    "strings"
)

type HttpHandler interface {
    Hello(w http.ResponseWriter, r *http.Request)
}

type HttpHandlerImpl struct {
    redisClient RedisClient
    greetingLabel string
}

func (h HttpHandlerImpl) Hello(w http.ResponseWriter, r *http.Request) {
    count := strconv.Itoa(h.redisClient.Incr("backend-golang-counter"))
    name := strings.TrimPrefix(r.URL.Path, "/")
    message := "[GOLANG] " + h.greetingLabel + " " + name + " (call #" + count + ")"
    _, err := w.Write([]byte(message))
    if err != nil {
        log.Printf("Error when sending response %v", err)
    }
}

func NewHttpHandler(redisClient RedisClient, greetingLabel string) HttpHandler {
    return HttpHandlerImpl{ redisClient, greetingLabel }
}