Minor refactoring for mail rate limits

application/src/main/java/org/thingsboard/server/service/mail/DefaultMailService.java

@@ -41,6 +41,7 @@ import org.thingsboard.server.common.data.ApiUsageRecordKey;
 import org.thingsboard.server.common.data.ApiUsageRecordState;
 import org.thingsboard.server.common.data.ApiUsageStateValue;
 import org.thingsboard.server.common.data.StringUtils;
+import org.thingsboard.server.common.data.exception.RateLimitExceededException;
 import org.thingsboard.server.common.data.exception.ThingsboardErrorCode;
 import org.thingsboard.server.common.data.exception.ThingsboardException;
 import org.thingsboard.server.common.data.id.CustomerId;
@@ -225,7 +226,7 @@ public class DefaultMailService implements MailService {
         if (apiUsageStateService.getApiUsageState(tenantId).isEmailSendEnabled()) {
             if (tenantId != null && !tenantId.isSysTenantId() && StringUtils.isNotEmpty(perTenantRateLimitConfig) &&
                     !rateLimitService.checkRateLimit(LimitedApi.EMAILS, (Object) tenantId, perTenantRateLimitConfig)) {
-                throw new ThingsboardException("Rate limit for emails sending is exceeded", ThingsboardErrorCode.TOO_MANY_REQUESTS);
+                throw new RateLimitExceededException(LimitedApi.EMAILS);
             }
             try {
                 MimeMessage mailMsg = javaMailSender.createMimeMessage();

common/data/src/main/java/org/thingsboard/server/common/data/exception/RateLimitExceededException.java

@@ -0,0 +1,30 @@
+/**
+ * Copyright © 2016-2024 The Thingsboard Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.thingsboard.server.common.data.exception;
+
+import org.thingsboard.server.common.data.limit.LimitedApi;
+
+public class RateLimitExceededException extends AbstractRateLimitException {
+
+    public RateLimitExceededException(String message) {
+        super(message);
+    }
+
+    public RateLimitExceededException(LimitedApi api) {
+        super("Rate limit for " + api.getLabel() + " is exceeded");
+    }
+
+}

common/data/src/main/java/org/thingsboard/server/common/data/limit/LimitedApi.java

@@ -40,7 +40,7 @@ public enum LimitedApi {
     TWO_FA_VERIFICATION_CODE_CHECK(false, true),
     TRANSPORT_MESSAGES_PER_TENANT("transport messages", true),
     TRANSPORT_MESSAGES_PER_DEVICE("transport messages per device", false),
-    EMAILS("emails", true);
+    EMAILS("emails sending", true);
 
     private Function<DefaultTenantProfileConfiguration, String> configExtractor;
     @Getter