Mail Send Timeouts

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

@@ -85,10 +85,8 @@ public class DefaultMailService implements MailService {
     @Autowired
     private MailExecutorService mailExecutorService;
 
-    @Value("${actors.rule.mail_timeout_thread_pool_size}")
-    private int timeoutExecutorPoolSize;
-
-    private ExecutorService timeoutExecutorService;
+    @Autowired
+    private PasswordResetExecutorService passwordResetExecutorService;
 
     private JavaMailSenderImpl mailSender;
 
@@ -106,14 +104,6 @@ public class DefaultMailService implements MailService {
     @PostConstruct
     private void init() {
         updateMailConfiguration();
-        timeoutExecutorService = Executors.newFixedThreadPool(timeoutExecutorPoolSize);
-    }
-
-    @PreDestroy
-    private void destroy() {
-        if (timeoutExecutorService != null) {
-            timeoutExecutorService.shutdown();
-        }
     }
 
     @Override
@@ -252,7 +242,7 @@ public class DefaultMailService implements MailService {
 
     @Override
     public void sendResetPasswordEmailAsync(String passwordResetLink, String email) {
-        mailExecutorService.execute(() -> {
+        passwordResetExecutorService.execute(() -> {
             try {
                 this.sendResetPasswordEmail(passwordResetLink, email);
             } catch (ThingsboardException e) {
@@ -489,9 +479,8 @@ public class DefaultMailService implements MailService {
     }
 
     private void sendMailWithTimeout(JavaMailSender mailSender, MimeMessage msg, long timeout) {
-        var submittedMail = timeoutExecutorService.submit(() -> mailSender.send(msg));
         try {
-            submittedMail.get(timeout, TimeUnit.MILLISECONDS);
+            mailExecutorService.submit(() -> mailSender.send(msg)).get(timeout, TimeUnit.MILLISECONDS);
         } catch (TimeoutException e) {
             log.debug("Error during mail submission", e);
             throw new RuntimeException("Timeout!");

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

@@ -0,0 +1,33 @@
+/**
+ * Copyright © 2016-2022 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.service.mail;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+import org.thingsboard.common.util.AbstractListeningExecutor;
+
+@Component
+public class PasswordResetExecutorService extends AbstractListeningExecutor {
+
+    @Value("${actors.rule.mail_password_reset_thread_pool_size:10}")
+    private int mailExecutorThreadPoolSize;
+
+    @Override
+    protected int getThreadPollSize() {
+        return mailExecutorThreadPoolSize;
+    }
+
+}

application/src/main/resources/thingsboard.yml

@@ -327,8 +327,8 @@ actors:
     js_thread_pool_size: "${ACTORS_RULE_JS_THREAD_POOL_SIZE:50}"
     # Specify thread pool size for mail sender executor service
     mail_thread_pool_size: "${ACTORS_RULE_MAIL_THREAD_POOL_SIZE:40}"
-    # Specify thread pool size for mail sender executor service
-    mail_timeout_thread_pool_size: "${ACTORS_RULE_MAIL_TIMEOUT_THREAD_POOL_SIZE:10}"
+    # Specify thread pool size for password reset emails
+    mail_password_reset_thread_pool_size: "${ACTORS_RULE_MAIL_PASSWORD_RESET_THREAD_POOL_SIZE:10}"
     # Specify thread pool size for sms sender executor service
     sms_thread_pool_size: "${ACTORS_RULE_SMS_THREAD_POOL_SIZE:50}"
     # Whether to allow usage of system mail service for rules

common/util/src/main/java/org/thingsboard/common/util/AbstractListeningExecutor.java

@@ -49,6 +49,10 @@ public abstract class AbstractListeningExecutor implements ListeningExecutor {
         return service.submit(task);
     }
 
+    public ListenableFuture<?> executeAsync(Runnable task) {
+        return service.submit(task);
+    }
+
     @Override
     public void execute(Runnable command) {
         service.execute(command);

common/util/src/main/java/org/thingsboard/common/util/ListeningExecutor.java

@@ -24,8 +24,14 @@ public interface ListeningExecutor extends Executor {
 
     <T> ListenableFuture<T> executeAsync(Callable<T> task);
 
+    ListenableFuture<?> executeAsync(Runnable task);
+
     default <T> ListenableFuture<T> submit(Callable<T> task) {
         return executeAsync(task);
     }
 
+    default ListenableFuture<?> submit(Runnable task) {
+        return executeAsync(task);
+    }
+
 }