feat: 즉시 메일 전송 API 구현

build.gradle

@@ -36,6 +36,7 @@ dependencies {
     runtimeOnly 'com.mysql:mysql-connector-j'
     annotationProcessor 'org.projectlombok:lombok'
     testImplementation 'org.springframework.boot:spring-boot-starter-test'
+    implementation 'org.springframework.boot:spring-boot-starter-mail'
 }
 
 dependencyManagement {

src/main/java/com/yeongjin/alarmserver/domain/emailalarm/service/EmailAlarmService.java

@@ -4,15 +4,22 @@
 import com.yeongjin.alarmserver.domain.emailalarm.dto.request.ScheduledEmailReq;
 import com.yeongjin.alarmserver.domain.emailalarm.entity.EmailAlarm;
 import com.yeongjin.alarmserver.domain.emailalarm.repository.EmailAlarmRepository;
+import jakarta.mail.MessagingException;
+import jakarta.mail.internet.MimeMessage;
 import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.mail.javamail.JavaMailSender;
+import org.springframework.mail.javamail.MimeMessageHelper;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
 @Service
 @RequiredArgsConstructor
 @Transactional(readOnly = true)
+@Slf4j
 public class EmailAlarmService {
     private final EmailAlarmRepository emailAlarmRepository;
+    private final JavaMailSender javaMailSender;
 
     @Transactional
     public Long sendImmediateEmail(ImmediateEmailReq immediateEmailReq) {
@@ -23,6 +30,20 @@ public Long sendImmediateEmail(ImmediateEmailReq immediateEmailReq) {
                         immediateEmailReq.getContent()
                 )
         );
+
+        MimeMessage mimeMessage = javaMailSender.createMimeMessage();
+        try {
+            MimeMessageHelper mimeMessageHelper = new MimeMessageHelper(mimeMessage, false, "UTF-8");
+            mimeMessageHelper.setTo(immediateEmailReq.getRecipients().toArray(new String[0]));
+            mimeMessageHelper.setSubject(immediateEmailReq.getSubject());
+            mimeMessageHelper.setText(immediateEmailReq.getContent(), false);
+            javaMailSender.send(mimeMessage);
+            log.info("Success");
+        } catch (MessagingException e) {
+            log.info("Fail");
+            throw new RuntimeException(e);
+        }
+
         return emailAlarm.getId();
     }