Auth: Add option for case insensitive login (#49262)

* add case insensitive option

* treat id as case insensitive

* Users: Add integration tests for case insensitive querying

* Prefer config struct to global variable

* change key to case_insensitive_login

* impede conflicting users from logging in

* add tests for impeding user retrieval if conflicting

* nits and picks

Co-authored-by: gamab <gabi.mabs@gmail.com>

* Add check in transaction for conflicting user

Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>

* add update tests

* skip on mysql

* add custom messages for user admin view

Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>

* nit: extra else

* linting mistake

Co-authored-by: gamab <gabi.mabs@gmail.com>
Co-authored-by: Gabriel MABILLE <gamab@users.noreply.github.com>

pkg/api/user.go

@@ -136,12 +136,15 @@ func (hs *HTTPServer) handleUpdateUser(ctx context.Context, cmd models.UpdateUse
 	if len(cmd.Login) == 0 {
 		cmd.Login = cmd.Email
 		if len(cmd.Login) == 0 {
-			return response.Error(400, "Validation error, need to specify either username or email", nil)
+			return response.Error(http.StatusBadRequest, "Validation error, need to specify either username or email", nil)
 		}
 	}
 
 	if err := hs.SQLStore.UpdateUser(ctx, &cmd); err != nil {
-		return response.Error(500, "Failed to update user", err)
+		if errors.Is(err, models.ErrCaseInsensitive) {
+			return response.Error(http.StatusConflict, "Update would result in user login conflict", err)
+		}
+		return response.Error(http.StatusInternalServerError, "Failed to update user", err)
 	}
 
 	return response.Success("User updated")

pkg/api/user_token.go

@@ -53,9 +53,13 @@ func (hs *HTTPServer) getUserAuthTokensInternal(c *models.ReqContext, userID int
 
 	if err := hs.SQLStore.GetUserById(c.Req.Context(), &userQuery); err != nil {
 		if errors.Is(err, models.ErrUserNotFound) {
-			return response.Error(404, "User not found", err)
+			return response.Error(http.StatusNotFound, "User not found", err)
+		} else if errors.Is(err, models.ErrCaseInsensitive) {
+			return response.Error(http.StatusConflict,
+				"User has conflicting login or email with another user. Please contact server admin", err)
 		}
-		return response.Error(500, "Failed to get user", err)
+
+		return response.Error(http.StatusInternalServerError, "Failed to get user", err)
 	}
 
 	tokens, err := hs.AuthTokenService.GetUserTokens(c.Req.Context(), userID)