CAPTCHAと2FAを実装

internal/service/captcha_service.go

@@ -0,0 +1,75 @@
+package service
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/dchest/captcha"
+)
+
+type CaptchaService struct {
+	captchaType        string
+	turnstileSecretKey string
+}
+
+func NewCaptchaService(captchaType, turnstileSecretKey string) *CaptchaService {
+	return &CaptchaService{
+		captchaType:        captchaType,
+		turnstileSecretKey: turnstileSecretKey,
+	}
+}
+
+func (s *CaptchaService) NewImageCaptcha() string {
+	return captcha.New()
+}
+func (s *CaptchaService) VerifyImageCaptcha(id, answer string) bool {
+	return captcha.VerifyString(id, answer)
+}
+
+type turnstileResponse struct {
+	Success bool     `json:"success"`
+	Errors  []string `json:"error-codes"`
+}
+
+func (s *CaptchaService) VerifyTurnstile(token, remoteIP string) (bool, error) {
+	if token == "" {
+		return false, nil
+	}
+
+	form := url.Values{}
+	form.Set("secret", s.turnstileSecretKey)
+	form.Set("response", token)
+	if remoteIP != "" {
+		form.Set("remoteip", remoteIP)
+	}
+
+	resp, err := http.Post(
+		"https://challenges.cloudflare.com/turnstile/v0/siteverify",
+		"application/x-www-form-urlencoded",
+		strings.NewReader(form.Encode()),
+	)
+	if err != nil {
+		return false, fmt.Errorf("turnstile request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return false, fmt.Errorf("reading turnstile response: %w", err)
+	}
+
+	var result turnstileResponse
+	if err := json.Unmarshal(body, &result); err != nil {
+		return false, fmt.Errorf("parsing turnstile response: %w", err)
+	}
+
+	return result.Success, nil
+}
+
+func (s *CaptchaService) Type() string {
+	return s.captchaType
+}