feat(tests): add number fact test in go (#60)

tests/containers/number-fact-go/main.go

@@ -0,0 +1,102 @@
+package main
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"log"
+	"math/big"
+	"net/http"
+	"strings"
+	"time"
+)
+
+func trialDivision(n *big.Int) []*big.Int {
+	var factors []*big.Int
+	zero := big.NewInt(0)
+	one := big.NewInt(1)
+	two := big.NewInt(2)
+
+	for new(big.Int).Mod(n, two).Cmp(zero) == 0 {
+		factors = append(factors, new(big.Int).Set(two))
+		n.Div(n, two)
+	}
+
+	i := big.NewInt(3)
+	for new(big.Int).Mul(i, i).Cmp(n) <= 0 {
+		for new(big.Int).Mod(n, i).Cmp(zero) == 0 {
+			factors = append(factors, new(big.Int).Set(i))
+			n.Div(n, i)
+		}
+		i.Add(i, two)
+	}
+
+	if n.Cmp(one) > 0 {
+		factors = append(factors, new(big.Int).Set(n))
+	}
+
+	return factors
+}
+
+func hashFactors(factors []*big.Int) string {
+	var sb strings.Builder
+	for _, factor := range factors {
+		sb.WriteString(factor.String())
+	}
+	hash := sha256.Sum256([]byte(sb.String()))
+	return hex.EncodeToString(hash[:])
+}
+
+type Response struct {
+	Fatores []string `json:"fatores"`
+	Sha     string   `json:"sha"`
+}
+
+func factorHandler(w http.ResponseWriter, r *http.Request) {
+	param := r.URL.Query().Get("number")
+	if param == "" {
+		http.Error(w, "Missing 'number' parameter", http.StatusBadRequest)
+		return
+	}
+
+	num := new(big.Int)
+	_, ok := num.SetString(param, 10)
+	if !ok {
+		http.Error(w, "Invalid 'number' parameter", http.StatusBadRequest)
+		return
+	}
+
+	factorsChan := make(chan []*big.Int)
+	go func() {
+		factorsChan <- trialDivision(num)
+	}()
+
+	select {
+	case factors := <-factorsChan:
+		var factorsStr []string
+		for _, factor := range factors {
+			factorsStr = append(factorsStr, factor.String())
+		}
+
+		hash := hashFactors(factors)
+
+		response := Response{
+			Fatores: factorsStr,
+			Sha:     hash,
+		}
+
+		w.Header().Set("Content-Type", "application/json")
+		json.NewEncoder(w).Encode(response)
+
+	case <-time.After(200 * time.Second):
+		http.Error(w, "Request timed out", http.StatusRequestTimeout)
+	}
+}
+
+func main() {
+	http.HandleFunc("/factors", factorHandler)
+
+	fmt.Println("Server is listening on port 8080...")
+	log.Fatal(http.ListenAndServe(":8080", nil))
+}