#12 Implement mail service

pom.xml

@@ -73,6 +73,16 @@
  <artifactId>spring-boot-starter-test</artifactId>
  <scope>test</scope>
  </dependency>
+
+ <dependency>
+ <groupId>org.springframework.boot</groupId>
+ <artifactId>spring-boot-starter-mail</artifactId>
+ </dependency>
+
+ <dependency>
+ <groupId>org.springframework.boot</groupId>
+ <artifactId>spring-boot-starter-freemarker</artifactId>
+ </dependency>
 
  <dependency>
  <groupId>com.graphql-java-kickstart</groupId>

src/main/java/com/example/tasklist/TasklistApplication.java

@@ -3,11 +3,13 @@
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.cache.annotation.EnableCaching;
+import org.springframework.scheduling.annotation.EnableScheduling;
 import org.springframework.transaction.annotation.EnableTransactionManagement;
 
 @SpringBootApplication
 @EnableTransactionManagement
 @EnableCaching
+@EnableScheduling
 public class TasklistApplication {
 
  public static void main(final String[] args) {

src/main/java/com/example/tasklist/config/MailConfig.java

@@ -0,0 +1,28 @@
+package com.example.tasklist.config;
+
+import com.example.tasklist.service.props.MailProperties;
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.JavaMailSenderImpl;
+
+@Configuration
+@RequiredArgsConstructor
+public class MailConfig {
+
+ private final MailProperties mailProperties;
+
+ @Bean
+ public JavaMailSender mailSender() {
+ JavaMailSenderImpl mailSender = new JavaMailSenderImpl();
+ mailSender.setHost(mailProperties.getHost());
+ mailSender.setPort(mailProperties.getPort());
+ mailSender.setUsername(mailProperties.getUsername());
+ mailSender.setPassword(mailProperties.getPassword());
+ mailSender.setJavaMailProperties(mailProperties.getProperties());
+ mailSender.getJavaMailProperties();
+ return mailSender;
+ }
+
+}

src/main/java/com/example/tasklist/domain/MailType.java

@@ -0,0 +1,8 @@
+package com.example.tasklist.domain;
+
+public enum MailType {
+
+ REGISTRATION,
+ REMINDER
+
+}

src/main/java/com/example/tasklist/repository/TaskRepository.java

@@ -6,6 +6,7 @@
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
 
+import java.sql.Timestamp;
 import java.util.List;
 
 public interface TaskRepository extends JpaRepository<Task, Long> {
@@ -17,6 +18,14 @@ public interface TaskRepository extends JpaRepository<Task, Long> {
  """, nativeQuery = true)
  List<Task> findAllByUserId(@Param("userId") Long userId);
 
+ @Query(value = """
+ SELECT * FROM tasks t
+ WHERE t.expiration_date is not null
+ AND t.expiration_date between :start and :end
+ """, nativeQuery = true)
+ List<Task> findAllSoonTasks(@Param("start") Timestamp start,
+ @Param("end") Timestamp end);
+
  @Modifying
  @Query(value = """
  INSERT INTO users_tasks (user_id, task_id)

src/main/java/com/example/tasklist/repository/UserRepository.java

@@ -11,6 +11,17 @@ public interface UserRepository extends JpaRepository<User, Long> {
 
  Optional<User> findByUsername(String username);
 
+ @Query(value = """
+ SELECT u.id as id,
+ u.name as name,
+ u.username as username,
+ u.password as password
+ FROM users_tasks ut
+ JOIN users u ON ut.user_id = u.id
+ WHERE ut.task_id = :taskId
+ """, nativeQuery = true)
+ Optional<User> findTaskAuthor(@Param("taskId") Long taskId);
+
  @Query(value = """
  SELECT exists(
  SELECT 1

src/main/java/com/example/tasklist/service/MailService.java

@@ -0,0 +1,12 @@
+package com.example.tasklist.service;
+
+import com.example.tasklist.domain.MailType;
+import com.example.tasklist.domain.user.User;
+
+import java.util.Properties;
+
+public interface MailService {
+
+ void sendEmail(User user, MailType type, Properties params);
+
+}

src/main/java/com/example/tasklist/service/Reminder.java

@@ -0,0 +1,7 @@
+package com.example.tasklist.service;
+
+public interface Reminder {
+
+ void remindForTask();
+
+}

src/main/java/com/example/tasklist/service/TaskService.java

@@ -3,6 +3,7 @@
 import com.example.tasklist.domain.task.Task;
 import com.example.tasklist.domain.task.TaskImage;
 
+import java.time.Duration;
 import java.util.List;
 
 public interface TaskService {
@@ -11,6 +12,8 @@ public interface TaskService {
 
  List<Task> getAllByUserId(Long id);
 
+ List<Task> getAllSoonTasks(Duration duration);
+
  Task update(Task task);
 
  Task create(Task task, Long userId);

src/main/java/com/example/tasklist/service/UserService.java

@@ -14,6 +14,8 @@ public interface UserService {
 
  boolean isTaskOwner(Long userId, Long taskId);
 
+ User getTaskAuthor(Long taskId);
+
  void delete(Long id);
 
 }

src/main/java/com/example/tasklist/service/impl/MailServiceImpl.java

@@ -0,0 +1,89 @@
+package com.example.tasklist.service.impl;
+
+import com.example.tasklist.domain.MailType;
+import com.example.tasklist.domain.user.User;
+import com.example.tasklist.service.MailService;
+import freemarker.template.Configuration;
+import jakarta.mail.internet.MimeMessage;
+import lombok.RequiredArgsConstructor;
+import lombok.SneakyThrows;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
+import org.springframework.stereotype.Service;
+
+import java.io.StringWriter;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Properties;
+
+@Service
+@RequiredArgsConstructor
+public class MailServiceImpl implements MailService {
+
+ private final Configuration configuration;
+ private final JavaMailSender mailSender;
+
+ @Override
+ public void sendEmail(final User user,
+ final MailType type,
+ final Properties params) {
+ switch (type) {
+ case REGISTRATION -> sendRegistrationEmail(user, params);
+ case REMINDER -> sendReminderEmail(user, params);
+ default -> {
+ }
+ }
+ }
+
+ @SneakyThrows
+ private void sendRegistrationEmail(final User user,
+ final Properties params) {
+ MimeMessage mimeMessage = mailSender.createMimeMessage();
+ MimeMessageHelper helper = new MimeMessageHelper(mimeMessage,
+ false,
+ "UTF-8");
+ helper.setSubject("Thank you for registration, " + user.getName());
+ helper.setTo(user.getUsername());
+ String emailContent = getRegistrationEmailContent(user, params);
+ helper.setText(emailContent, true);
+ mailSender.send(mimeMessage);
+ }
+
+ @SneakyThrows
+ private void sendReminderEmail(final User user, final Properties params) {
+ MimeMessage mimeMessage = mailSender.createMimeMessage();
+ MimeMessageHelper helper = new MimeMessageHelper(mimeMessage,
+ false,
+ "UTF-8");
+ helper.setSubject("You have task to do in 1 hour");
+ helper.setTo(user.getUsername());
+ String emailContent = getReminderEmailContent(user, params);
+ helper.setText(emailContent, true);
+ mailSender.send(mimeMessage);
+ }
+
+ @SneakyThrows
+ private String getRegistrationEmailContent(final User user,
+ final Properties properties) {
+ StringWriter writer = new StringWriter();
+ Map<String, Object> model = new HashMap<>();
+ model.put("name", user.getName());
+ configuration.getTemplate("register.ftlh")
+ .process(model, writer);
+ return writer.getBuffer().toString();
+ }
+
+ @SneakyThrows
+ private String getReminderEmailContent(final User user,
+ final Properties properties) {
+ StringWriter writer = new StringWriter();
+ Map<String, Object> model = new HashMap<>();
+ model.put("name", user.getName());
+ model.put("title", properties.getProperty("task.title"));
+ model.put("description", properties.getProperty("task.description"));
+ configuration.getTemplate("reminder.ftlh")
+ .process(model, writer);
+ return writer.getBuffer().toString();
+ }
+
+}

src/main/java/com/example/tasklist/service/impl/ReminderImpl.java

@@ -0,0 +1,41 @@
+package com.example.tasklist.service.impl;
+
+import com.example.tasklist.domain.MailType;
+import com.example.tasklist.domain.task.Task;
+import com.example.tasklist.domain.user.User;
+import com.example.tasklist.service.MailService;
+import com.example.tasklist.service.Reminder;
+import com.example.tasklist.service.TaskService;
+import com.example.tasklist.service.UserService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Service;
+
+import java.time.Duration;
+import java.util.List;
+import java.util.Properties;
+
+@Service
+@RequiredArgsConstructor
+public class ReminderImpl implements Reminder {
+
+ private final TaskService taskService;
+ private final UserService userService;
+ private final MailService mailService;
+ private final Duration duration = Duration.ofHours(1);
+
+ // @Scheduled(cron = "0 0 * * * *")
+ @Scheduled(cron = "0 * * * * *")
+ @Override
+ public void remindForTask() {
+ List<Task> tasks = taskService.getAllSoonTasks(duration);
+ tasks.forEach(task -> {
+ User user = userService.getTaskAuthor(task.getId());
+ Properties properties = new Properties();
+ properties.setProperty("task.title", task.getTitle());
+ properties.setProperty("task.description", task.getDescription());
+ mailService.sendEmail(user, MailType.REMINDER, properties);
+ });
+ }
+
+}

src/main/java/com/example/tasklist/service/impl/TaskServiceImpl.java

@@ -14,6 +14,9 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.sql.Timestamp;
+import java.time.Duration;
+import java.time.LocalDateTime;
 import java.util.List;
 
 @Service
@@ -38,6 +41,14 @@ public List<Task> getAllByUserId(final Long id) {
  return taskRepository.findAllByUserId(id);
  }
 
+ @Override
+ @Transactional(readOnly = true)
+ public List<Task> getAllSoonTasks(final Duration duration) {
+ LocalDateTime now = LocalDateTime.now();
+ return taskRepository.findAllSoonTasks(Timestamp.valueOf(now),
+ Timestamp.valueOf(now.plus(duration)));
+ }
+
  @Override
  @Transactional
  @CachePut(value = "TaskService::getById", key = "#task.id")

src/main/java/com/example/tasklist/service/impl/UserServiceImpl.java

@@ -1,9 +1,11 @@
 package com.example.tasklist.service.impl;
 
+import com.example.tasklist.domain.MailType;
 import com.example.tasklist.domain.exception.ResourceNotFoundException;
 import com.example.tasklist.domain.user.Role;
 import com.example.tasklist.domain.user.User;
 import com.example.tasklist.repository.UserRepository;
+import com.example.tasklist.service.MailService;
 import com.example.tasklist.service.UserService;
 import lombok.RequiredArgsConstructor;
 import org.springframework.cache.annotation.CacheEvict;
@@ -14,6 +16,7 @@
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.util.Properties;
 import java.util.Set;
 
 @Service
@@ -22,6 +25,7 @@ public class UserServiceImpl implements UserService {
 
  private final UserRepository userRepository;
  private final PasswordEncoder passwordEncoder;
+ private final MailService mailService;
 
  @Override
  @Transactional(readOnly = true)
@@ -78,6 +82,7 @@ public User create(final User user) {
  Set<Role> roles = Set.of(Role.ROLE_USER);
  user.setRoles(roles);
  userRepository.save(user);
+ mailService.sendEmail(user, MailType.REGISTRATION, new Properties());
  return user;
  }
 
@@ -89,6 +94,16 @@ public boolean isTaskOwner(final Long userId, final Long taskId) {
  return userRepository.isTaskOwner(userId, taskId);
  }
 
+ @Override
+ @Transactional(readOnly = true)
+ @Cacheable(value = "UserService::getTaskAuthor",
+ key = "#taskId")
+ public User getTaskAuthor(final Long taskId) {
+ return userRepository.findTaskAuthor(taskId)
+ .orElseThrow(() ->
+ new ResourceNotFoundException("User not found."));
+ }
+
  @Override
  @Transactional
  @CacheEvict(value = "UserService::getById", key = "#id")

src/main/java/com/example/tasklist/service/props/MailProperties.java

@@ -0,0 +1,20 @@
+package com.example.tasklist.service.props;
+
+import lombok.Data;
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.stereotype.Component;
+
+import java.util.Properties;
+
+@Component
+@Data
+@ConfigurationProperties(prefix = "spring.mail")
+public class MailProperties {
+
+ private String host;
+ private int port;
+ private String username;
+ private String password;
+ private Properties properties;
+
+}