func backend()

in server/cmd/harp-server/internal/dispatchers/http/routes/backend.go [34:80]
36 lines of code
6 McCabe index (conditional complexity)

func backend(namespace string, engine storage.Engine) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var (
			ctx    = r.Context()
			id     = r.URL.Path
			keyRaw = r.URL.Query().Get("key")
		)

		// Remove namespace prefix
		identifier := strings.TrimPrefix(id, fmt.Sprintf("/%s", namespace))

		// Retrieve secret from engine
		secret, err := engine.Get(ctx, identifier)
		if errors.Is(err, storage.ErrSecretNotFound) {
			http.Error(w, "secret not found", http.StatusNotFound)
			return
		}
		if err != nil {
			log.For(ctx).Error("unable to retrieve secret from engine", zap.Error(err), zap.String("url", r.URL.String()))
			http.Error(w, "unable to retrieve secret", http.StatusBadRequest)
			return
		}

		// key is defined
		if keyRaw != "" {
			// Retrieve transformer from key
			transformer, err := encryption.FromKey(keyRaw)
			if err != nil {
				log.For(ctx).Error("unable to initialize secret transformer", zap.String("url", r.URL.String()))
				http.Error(w, "unable to initialize secret transformer", http.StatusInternalServerError)
				return
			}

			// Apply transformation to secret value
			secret, err = transformer.To(ctx, secret)
			if err != nil {
				log.For(ctx).Error("unable to protect secret", zap.String("url", r.URL.String()))
				http.Error(w, "unable to protect secret", http.StatusBadRequest)
				return
			}
		}

		// Send result
		w.WriteHeader(http.StatusOK)
		fmt.Fprintf(w, "%s", secret)
	}
}