refactor: error handling

Author: raphico

docs/database.md

@@ -51,7 +51,7 @@ Tracks user devices, type, status, and optional metadata.
   "user_id": "uuid-1234",
   "name": "Living Room Sensor",
   "device_type": "temperature_sensor",
-  "status": "Online",
+  "status": "online",
   "metadata": {
     "manufacturer": "AcmeSensors",
     "firmware_version": "v1.2.3",

internal/http/auth_handler.go

@@ -54,30 +54,21 @@ func (h *AuthHandler) RegisterUser(w http.ResponseWriter, r *http.Request) {
 	u, err := h.auth.Register(r.Context(), req.Username, req.Email, req.Password)
 	if err != nil {
 		switch {
-		case errors.Is(err, user.ErrEmailInvalid),
-			errors.Is(err, user.ErrEmailRequired):
-			WriteJSONError(w, http.StatusBadRequest, invalidEmail, err.Error())
-			return
-
 		case errors.Is(err, user.ErrUsernameRequired),
 			errors.Is(err, user.ErrUsernameTooShort),
 			errors.Is(err, user.ErrUsernameTooLong),
-			errors.Is(err, user.ErrUsernameInvalidChars):
-			WriteJSONError(w, http.StatusBadRequest, invalidUsername, err.Error())
-			return
-
-		case errors.Is(err, user.ErrPasswordRequired),
+			errors.Is(err, user.ErrEmailInvalid),
+			errors.Is(err, user.ErrEmailRequired),
+			errors.Is(err, user.ErrPasswordRequired),
 			errors.Is(err, user.ErrPasswordTooShort),
-			errors.Is(err, user.ErrPasswordTooWeak):
-			WriteJSONError(w, http.StatusBadRequest, invalidPassword, err.Error())
-			return
-
-		case errors.Is(err, user.ErrEmailAlreadyExists):
-			WriteJSONError(w, http.StatusConflict, emailExists, err.Error())
+			errors.Is(err, user.ErrPasswordTooWeak),
+			errors.Is(err, user.ErrUsernameInvalidChars):
+			WriteJSONError(w, http.StatusBadRequest, invalidRequest, err.Error())
 			return
 
-		case errors.Is(err, user.ErrUsernameTaken):
-			WriteJSONError(w, http.StatusConflict, usernameExists, err.Error())
+		case errors.Is(err, user.ErrEmailAlreadyExists),
+			errors.Is(err, user.ErrUsernameTaken):
+			WriteJSONError(w, http.StatusConflict, conflict, err.Error())
 			return
 
 		default:
@@ -116,7 +107,7 @@ func (h *AuthHandler) LoginUser(w http.ResponseWriter, r *http.Request) {
 	accessToken, refreshToken, err := h.auth.Login(r.Context(), req.Email, req.Password)
 	if err != nil {
 		if errors.Is(err, user.ErrInvalidCredentials) {
-			WriteJSONError(w, http.StatusUnauthorized, invalidCredentials, "Invalid credentials")
+			WriteJSONError(w, http.StatusUnauthorized, invalidRequest, "Invalid credentials")
 			return
 		}
 
@@ -155,7 +146,7 @@ func (h *AuthHandler) RefreshAccessToken(w http.ResponseWriter, r *http.Request)
 	if err != nil {
 		switch {
 		case errors.Is(err, token.ErrTokenNotFound):
-			WriteJSONError(w, http.StatusUnauthorized, invalidGrant, "Invalid or expired refresh token")
+			WriteJSONError(w, http.StatusUnauthorized, unauthorized, "Invalid or expired refresh token")
 		default:
 			h.log.Error(fmt.Sprintf("failed to refresh access token: %v", err))
 			WriteInternalError(w)

internal/http/device_handler.go

@@ -62,7 +62,7 @@ func (h *DeviceHandler) HandleCreateDevice(w http.ResponseWriter, r *http.Reques
 			errors.Is(err, device.ErrInvalidStatus),
 			errors.Is(err, device.ErrInvalidDeviceType),
 			errors.Is(err, device.ErrInvalidMetadata):
-			WriteJSONError(w, http.StatusBadRequest, validationError, err.Error())
+			WriteJSONError(w, http.StatusBadRequest, invalidRequest, err.Error())
 			return
 
 		case errors.Is(err, user.ErrUserNotFound):
@@ -86,3 +86,7 @@ func (h *DeviceHandler) HandleCreateDevice(w http.ResponseWriter, r *http.Reques
 
 	WriteJSON(w, http.StatusCreated, res, nil)
 }
+
+func (h *DeviceHandler) HandleGetDeviceById(w http.ResponseWriter, r *http.Request) {
+
+}

internal/http/errors.go

@@ -3,18 +3,8 @@ package http
 type errorCode string
 
 const (
-	invalidRequest  errorCode = "INVALID_REQUEST"
-	invalidEmail    errorCode = "INVALID_EMAIL"
-	invalidUsername errorCode = "INVALID_USERNAME"
-	invalidPassword errorCode = "INVALID_PASSWORD"
-	unauthorized    errorCode = "UNAUTHORIZED"
-
-	invalidCredentials errorCode = "INVALID_CREDENTIALS"
-	invalidGrant       errorCode = "INVALID_GRANT"
-	validationError    errorCode = "VALIDATION_ERROR"
-
-	emailExists    errorCode = "EMAIL_EXISTS"
-	usernameExists errorCode = "USERNAME_EXISTS"
-
-	internalError errorCode = "INTERNAL_ERROR"
+	invalidRequest errorCode = "INVALID_REQUEST" // includes validation errors
+	unauthorized   errorCode = "UNAUTHORIZED"    // invalid token, creds, grant
+	conflict       errorCode = "CONFLICT"        // duplicate email/username
+	internalError  errorCode = "INTERNAL_ERROR"  // unexpected server error
 )