server.go

package main

import (
	"encoding/json"
	"log"
	"math/rand"
	"net/http"
	"time"
)

type MsgError struct {
	Msg string `json:"msg"`
}

type Actions struct {
	ID           string   `json:"id"`
	Value        float64  `json:"value"`
	PaidAt       string   `json:"paid_at"`
	IPLocation   string   `json:"ip_location"`
	CardHoldName string   `json:"card_hold_name"`
	Customer     Customer `json:"customer"`
}

type Customer struct {
	ID        string `json:"id"`
	Name      string `json:"name"`
	BirthDate string `json:"birth_date"`
	State     string `json:"state"`
	Phone     string `json:"phone"`
}

type ActionOutput struct {
	ID        string `json:"id"`
	Value      int `json:"value"`
}

var (
	PORT   = ":8081"
	msgErr MsgError
)

func Score(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		w.WriteHeader(http.StatusMethodNotAllowed)
		w.Write(JsonMsg("O metodo permitido é somente POST"))
		return
	}

	var a []Actions
	err := json.NewDecoder(r.Body).Decode(&a)
	if err != nil {
		w.WriteHeader(http.StatusBadRequest)
		w.Write(JsonMsg(err.Error()))
		return
	}

	var aoutv []ActionOutput
	for _, v := range a {
		var aout ActionOutput
		aout.ID = v.ID
		aout.Value = ScoreFunc(v.ID)
		aoutv = append(aoutv,aout)
	}
	b, err := json.Marshal(aoutv)
	if err!=nil {
		w.WriteHeader(http.StatusBadRequest)
		w.Write(JsonMsg(err.Error()))
		return
	}
	w.WriteHeader(200)
	w.Write(b)
}

func ScoreFunc(id string) int {
	score := randInt(1,98)
	if score <= 10 && score > 0 {
		return randInt(0,score)
	}
	if score < 50 {
		return randInt(30,score+30)
	}
	if score >= 50 {
		return randInt(score,100)
	}
	return randInt(10,30)
}

func randInt(min int, max int) int {
	if min < max {
		return min + rand.Intn(max-min)
	}
	return 0
}

func JsonMsg(msg string) []byte {
	msgErr.Msg = msg
	b, err := json.Marshal(msgErr)
	if err != nil {
		log.Println(err)
		return []byte(`{"msg":"` + err.Error() + `"}`)
	}
	return b
}

func main() {
	mux := http.NewServeMux()
	mux.HandleFunc("/v1/score", Score)
	server :=
		&http.Server{
			Addr:           PORT,
			Handler:        mux,
			ReadTimeout:    time.Millisecond * 500,
			WriteTimeout:   time.Millisecond * 700,
			MaxHeaderBytes: 10485760, // 10MB
		}
	log.Printf("\nRun Server port: %s", PORT)
	if err := server.ListenAndServe(); err != nil {
		log.Printf("Eror while serving metrics: %s", err)
	}
}