feat: 회원가입 이메일 전송 비동기 구현 및 가지 않은 메일 처리해주는 스케줄러 생성

build.gradle

@@ -70,6 +70,9 @@ dependencies {
     annotationProcessor "com.querydsl:querydsl-apt:${dependencyManagement.importedProperties['querydsl.version']}:jakarta"
     annotationProcessor "jakarta.annotation:jakarta.annotation-api"
     annotationProcessor "jakarta.persistence:jakarta.persistence-api"
+
+    // mail-sender
+    implementation 'org.springframework.boot:spring-boot-starter-mail'
 }
 
 def generated = 'src/main/generated'

src/main/java/com/market/ElectronicMarketApplication.java

@@ -3,10 +3,12 @@
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.data.jpa.repository.config.EnableJpaAuditing;
+import org.springframework.scheduling.annotation.EnableAsync;
 
 import java.util.TimeZone;
 
 @EnableJpaAuditing
+@EnableAsync
 @SpringBootApplication
 public class ElectronicMarketApplication {
 

src/main/java/com/market/alarm/application/MailEventHandler.java

@@ -0,0 +1,25 @@
+package com.market.alarm.application;
+
+import com.market.alarm.domain.MailStorage;
+import com.market.member.domain.auth.RegisteredEvent;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.event.TransactionPhase;
+import org.springframework.transaction.event.TransactionalEventListener;
+
+@Slf4j
+@RequiredArgsConstructor
+@Service
+public class MailEventHandler {
+
+    private final MailService mailService;
+
+    @Async
+    @TransactionalEventListener(phase = TransactionPhase.AFTER_COMMIT)
+    public void sendMail(final RegisteredEvent event) {
+        MailStorage mailStorage = MailStorage.createDefault(event.getMemberId(), event.getEmail(), event.getNickname());
+        mailService.sendMail(mailStorage);
+    }
+}

src/main/java/com/market/alarm/application/MailScheduleService.java

@@ -0,0 +1,22 @@
+package com.market.alarm.application;
+
+import lombok.RequiredArgsConstructor;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Service;
+
+@RequiredArgsConstructor
+@Service
+public class MailScheduleService {
+
+    private final MailService mailService;
+
+    @Scheduled(cron = "0 */10 * * * *")
+    public void resendMail() {
+        mailService.resendMail();
+    }
+
+    @Scheduled(cron = "0 */15 * * * *")
+    public void deleteSendSuccessMails() {
+        mailService.deleteSuccessMails();
+    }
+}

src/main/java/com/market/alarm/application/MailService.java

@@ -0,0 +1,74 @@
+package com.market.alarm.application;
+
+import com.market.alarm.domain.MailSender;
+import com.market.alarm.domain.MailStorage;
+import com.market.alarm.domain.MailStorageRepository;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Propagation;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.List;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+@Slf4j
+@RequiredArgsConstructor
+@Service
+public class MailService {
+
+    private static final int THREAD_COUNT = 4;
+
+    private final MailStorageRepository mailStorageRepository;
+    private final MailSender mailSender;
+    private final AtomicBoolean isRunning = new AtomicBoolean(false);
+
+    @Transactional(propagation = Propagation.REQUIRES_NEW)
+    public void sendMail(final MailStorage mailStorage) {
+        send(mailStorage);
+    }
+
+    private void send(final MailStorage mailStorage) {
+        log.info("{} 번 유저 생성. 닉네임 : {}, 메일 발송 시도!", mailStorage.getReceiverId(), mailStorage.getReceiverNickname());
+
+        try {
+            mailSender.pushMail(mailStorage.getReceiverEmail(), mailStorage.getId(), mailStorage.getReceiverNickname());
+            mailStorage.updateStatusDone();
+            log.info("{} 번 유저 생성. 닉네임 : {}, 메일 발송 성공!", mailStorage.getReceiverId(), mailStorage.getReceiverNickname());
+        } catch (final Exception exception) {
+            handleErrors(mailStorage, exception);
+        }
+    }
+
+    private void handleErrors(final MailStorage mailStorage, final Exception exception) {
+        log.info("{} 번 유저 생성. 닉네임 : {}, 메일 발송 실패!", mailStorage.getReceiverId(), mailStorage.getReceiverNickname());
+        log.error(exception.getMessage());
+
+        mailStorage.updateStatusFail();
+        mailStorageRepository.save(mailStorage);
+    }
+
+    @Transactional
+    public void resendMail() {
+        List<MailStorage> sendFailureMails = mailStorageRepository.findAllByNotDone();
+
+        if (isRunning.compareAndSet(false, true)) {
+            ExecutorService executorService = Executors.newFixedThreadPool(THREAD_COUNT);
+
+            for (MailStorage sendFailureMail : sendFailureMails) {
+                executorService.submit(() -> send(sendFailureMail));
+            }
+
+            executorService.shutdown();
+            isRunning.set(false);
+            log.info("실패 메일 재전송 성공! 건수: {}", sendFailureMails.size());
+        }
+    }
+
+    @Transactional
+    public void deleteSuccessMails() {
+        mailStorageRepository.deleteAllByDoneMails();
+    }
+}

src/main/java/com/market/alarm/config/MailSource.java

@@ -0,0 +1,35 @@
+package com.market.alarm.config;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+
+@AllArgsConstructor
+@Getter
+public enum MailSource {
+
+    TITLE("E-market 회원가입 성공 안내"),
+    CONTENT("""
+                    <h1> E-market </h1>
+                    <br>
+                    <p>E-market 회원가입에 성공하셨습니다.<p>
+                    <br>
+                    <p>해당 이메일은 회원가입 성공 안내 메시지입니다.<p>
+                    <br>
+                    <p>회원가입 기념 쿠폰을 발급하였습니다.<p>
+                    <br>
+            """);
+
+    private final String message;
+
+    public static String getMailMessage(final Long id, final String nickname) {
+        String message = "";
+
+        message += TITLE.message;
+        message += "<div style='margin:100px;'>";
+        message += "<p>" + id + "번 유저인" + nickname + "님 환영합니다.<p>";
+        message += CONTENT.message;
+        message += "</div>";
+
+        return message;
+    }
+}

src/main/java/com/market/alarm/config/ResendScheduleRunner.java

@@ -0,0 +1,21 @@
+package com.market.alarm.config;
+
+import com.market.alarm.application.MailScheduleService;
+import lombok.RequiredArgsConstructor;
+import org.springframework.boot.ApplicationArguments;
+import org.springframework.boot.ApplicationRunner;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.context.annotation.Configuration;
+
+@RequiredArgsConstructor
+@ConditionalOnProperty(name = "schedule.mail", havingValue = "true")
+@Configuration
+public class ResendScheduleRunner implements ApplicationRunner {
+
+    private final MailScheduleService mailScheduleService;
+
+    @Override
+    public void run(final ApplicationArguments args) {
+        mailScheduleService.resendMail();
+    }
+}

src/main/java/com/market/alarm/domain/MailSender.java

@@ -0,0 +1,12 @@
+package com.market.alarm.domain;
+
+import jakarta.mail.MessagingException;
+
+import java.io.UnsupportedEncodingException;
+
+public interface MailSender {
+
+    void pushMail(final String receiver,
+                  final Long id,
+                  final String nickname) throws MessagingException, UnsupportedEncodingException;
+}

src/main/java/com/market/alarm/domain/MailStatus.java

@@ -0,0 +1,8 @@
+package com.market.alarm.domain;
+
+public enum MailStatus {
+
+    WAIT,
+    FAIL,
+    DONE
+}

src/main/java/com/market/alarm/domain/MailStorage.java

@@ -0,0 +1,70 @@
+package com.market.alarm.domain;
+
+import com.market.global.domain.BaseEntity;
+import jakarta.persistence.Embedded;
+import jakarta.persistence.Entity;
+import jakarta.persistence.EnumType;
+import jakarta.persistence.Enumerated;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@Builder
+@EqualsAndHashCode(of = "id", callSuper = false)
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@Entity
+public class MailStorage extends BaseEntity {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @Embedded
+    private Receiver receiver;
+
+    @Enumerated(value = EnumType.STRING)
+    private MailStatus mailStatus;
+
+    public static MailStorage createDefault(final Long memberId, final String email, final String nickname) {
+        return getMailStorage(memberId, email, nickname, MailStatus.WAIT);
+    }
+
+    public static MailStorage createByStatus(final Long memberId, final String email, final String nickname, final MailStatus mailStatus) {
+        return getMailStorage(memberId, email, nickname, mailStatus);
+    }
+
+    private static MailStorage getMailStorage(final Long memberId, final String email, final String nickname, final MailStatus mailStatus) {
+        return MailStorage.builder()
+                .receiver(Receiver.createDefault(memberId, email, nickname))
+                .mailStatus(mailStatus)
+                .build();
+    }
+
+    public void updateStatusFail() {
+        this.mailStatus = MailStatus.FAIL;
+    }
+
+    public void updateStatusDone() {
+        this.mailStatus = MailStatus.DONE;
+    }
+
+    public Long getReceiverId() {
+        return receiver.getMemberId();
+    }
+
+    public String getReceiverEmail() {
+        return receiver.getEmail();
+    }
+
+    public String getReceiverNickname() {
+        return receiver.getNickname();
+    }
+}

src/main/java/com/market/alarm/domain/MailStorageRepository.java

@@ -0,0 +1,12 @@
+package com.market.alarm.domain;
+
+import java.util.List;
+
+public interface MailStorageRepository {
+
+    void save(final MailStorage mailStorage);
+
+    List<MailStorage> findAllByNotDone();
+
+    void deleteAllByDoneMails();
+}

src/main/java/com/market/alarm/domain/Receiver.java

@@ -0,0 +1,28 @@
+package com.market.alarm.domain;
+
+import jakarta.persistence.Embeddable;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@Builder
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor(access = AccessLevel.PRIVATE)
+@Embeddable
+public class Receiver {
+
+    private Long memberId;
+    private String email;
+    private String nickname;
+
+    protected static Receiver createDefault(final Long memberId, final String email, final String nickname) {
+        return Receiver.builder()
+                .memberId(memberId)
+                .email(email)
+                .nickname(nickname)
+                .build();
+    }
+}

src/main/java/com/market/alarm/infrastructure/EmailSender.java

@@ -0,0 +1,55 @@
+package com.market.alarm.infrastructure;
+
+import com.market.alarm.config.MailSource;
+import com.market.alarm.domain.MailSender;
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.InternetAddress;
+import jakarta.mail.internet.MimeMessage;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.stereotype.Component;
+
+import java.io.UnsupportedEncodingException;
+
+import static jakarta.mail.Message.RecipientType.TO;
+
+@Slf4j
+@RequiredArgsConstructor
+@Component
+public class EmailSender implements MailSender {
+
+    private static final String CHARSET = "utf-8";
+    private static final String SUBTYPE = "html";
+
+    @Value("${mail.sender.email}")
+    private String email;
+
+    @Value("${mail.sender.name}")
+    private String name;
+
+    private final JavaMailSender javaMailSender;
+
+    @Override
+    public void pushMail(final String receiver,
+                         final Long id,
+                         final String nickname) throws MessagingException, UnsupportedEncodingException {
+        MimeMessage message = createMessage(receiver, id, nickname);
+        javaMailSender.send(message);
+    }
+
+
+    private MimeMessage createMessage(final String receiver,
+                                      final Long id,
+                                      final String nickname) throws MessagingException, UnsupportedEncodingException {
+        MimeMessage message = javaMailSender.createMimeMessage();
+
+        message.addRecipients(TO, receiver);
+        message.setSubject(MailSource.TITLE.getMessage());
+        message.setText(MailSource.getMailMessage(id, nickname), CHARSET, SUBTYPE);
+        message.setFrom(new InternetAddress(email, name));
+
+        return message;
+    }
+}