fix: SMTP 설정 누락 시 서버 기동 차단

src/main/java/com/fowoco/server/auth/infrastructure/notification/SmtpPasswordResetNotificationAdapter.java

@@ -4,9 +4,11 @@
 import java.time.Instant;
 import java.time.format.DateTimeFormatter;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.boot.mail.autoconfigure.MailProperties;
 import org.springframework.mail.SimpleMailMessage;
 import org.springframework.mail.javamail.JavaMailSender;
 import org.springframework.stereotype.Component;
+import org.springframework.util.StringUtils;
 import org.springframework.web.util.UriComponentsBuilder;
 
 @Component
@@ -22,13 +24,36 @@ public final class SmtpPasswordResetNotificationAdapter implements PasswordReset
 
     public SmtpPasswordResetNotificationAdapter(
             JavaMailSender mailSender,
-            PasswordResetNotificationProperties properties
+            PasswordResetNotificationProperties properties,
+            MailProperties mailProperties
     ) {
         properties.validateForSmtp();
+        validateMailProperties(mailProperties);
         this.mailSender = mailSender;
         this.properties = properties;
     }
 
+    private void validateMailProperties(MailProperties mailProperties) {
+        if (!StringUtils.hasText(mailProperties.getHost())) {
+            throw new IllegalStateException(
+                    "SPRING_MAIL_HOST must not be blank when the SMTP notification provider is enabled"
+            );
+        }
+        boolean authenticationRequired = Boolean.parseBoolean(
+                mailProperties.getProperties().getOrDefault("mail.smtp.auth", "false")
+        );
+        if (authenticationRequired && !StringUtils.hasText(mailProperties.getUsername())) {
+            throw new IllegalStateException(
+                    "SPRING_MAIL_USERNAME is required when SMTP authentication is enabled"
+            );
+        }
+        if (authenticationRequired && !StringUtils.hasText(mailProperties.getPassword())) {
+            throw new IllegalStateException(
+                    "SPRING_MAIL_PASSWORD is required when SMTP authentication is enabled"
+            );
+        }
+    }
+
     @Override
     public void sendResetLink(String email, String rawToken, Instant expiresAt) {
         SimpleMailMessage message = new SimpleMailMessage();

src/test/java/com/fowoco/server/auth/infrastructure/notification/PasswordResetSmtpConfigurationTest.java

@@ -1,11 +1,17 @@
 package com.fowoco.server.auth.infrastructure.notification;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+import static org.mockito.Mockito.mock;
 
 import com.fowoco.server.auth.application.port.PasswordResetNotificationPort;
+import java.net.URI;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.mail.autoconfigure.MailProperties;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.util.TestPropertyValues;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.mail.javamail.JavaMailSender;
 import org.springframework.test.context.ActiveProfiles;
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
@@ -15,7 +21,9 @@
         "app.auth.password-reset.notification.provider=smtp",
         "app.auth.password-reset.notification.from=no-reply@fowoco.test",
         "app.auth.password-reset.notification.reset-url=https://demo.fowoco.test/reset-password",
-        "app.auth.password-reset.notification.subject=FOWOCO 비밀번호 재설정"
+        "app.auth.password-reset.notification.subject=FOWOCO 비밀번호 재설정",
+        "spring.mail.host=smtp.fowoco.test",
+        "management.health.mail.enabled=false"
 })
 class PasswordResetSmtpConfigurationTest {
 
@@ -29,4 +37,34 @@ class PasswordResetSmtpConfigurationTest {
     void smtpProviderSelectsSmtpAdapterInsteadOfNoOp() {
         assertThat(notificationPort).isInstanceOf(SmtpPasswordResetNotificationAdapter.class);
     }
+
+    @Test
+    void blankMailHostPreventsSmtpContextStartup() {
+        JavaMailSender mailSender = mock(JavaMailSender.class);
+        PasswordResetNotificationProperties notificationProperties =
+                new PasswordResetNotificationProperties(
+                        "no-reply@fowoco.test",
+                        URI.create("https://demo.fowoco.test/reset-password"),
+                        "FOWOCO 비밀번호 재설정"
+                );
+        MailProperties mailProperties = new MailProperties();
+
+        assertThatThrownBy(() -> {
+            try (AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext()) {
+                TestPropertyValues.of("app.auth.password-reset.notification.provider=smtp")
+                        .applyTo(context);
+                context.registerBean(
+                        SmtpPasswordResetNotificationAdapter.class,
+                        () -> new SmtpPasswordResetNotificationAdapter(
+                                mailSender,
+                                notificationProperties,
+                                mailProperties
+                        )
+                );
+                context.refresh();
+                context.getBean(SmtpPasswordResetNotificationAdapter.class);
+            }
+        }).hasRootCauseInstanceOf(IllegalStateException.class)
+                .hasStackTraceContaining("SPRING_MAIL_HOST");
+    }
 }

src/test/java/com/fowoco/server/auth/infrastructure/notification/SmtpPasswordResetNotificationAdapterTest.java

@@ -8,6 +8,7 @@
 import java.net.URI;
 import java.time.Instant;
 import org.junit.jupiter.api.Test;
+import org.springframework.boot.mail.autoconfigure.MailProperties;
 import org.mockito.ArgumentCaptor;
 import org.springframework.mail.SimpleMailMessage;
 import org.springframework.mail.javamail.JavaMailSender;
@@ -23,7 +24,8 @@ void sendsResetLinkWithTokenAndExpiry() {
                         "no-reply@fowoco.test",
                         URI.create("https://demo.fowoco.test/reset-password"),
                         "FOWOCO 비밀번호 재설정"
-                )
+                ),
+                mailProperties("smtp.fowoco.test", false, null, null)
         );
         Instant expiresAt = Instant.parse("2026-08-07T06:30:00Z");
 
@@ -51,7 +53,8 @@ void rejectsUnsafeOrIncompleteSmtpConfiguration() {
                         "",
                         URI.create("https://demo.fowoco.test/reset-password"),
                         "FOWOCO 비밀번호 재설정"
-                )
+                ),
+                mailProperties("smtp.fowoco.test", false, null, null)
         )).isInstanceOf(IllegalStateException.class)
                 .hasMessageContaining("PASSWORD_RESET_MAIL_FROM");
 
@@ -61,8 +64,55 @@ void rejectsUnsafeOrIncompleteSmtpConfiguration() {
                         "no-reply@fowoco.test",
                         URI.create("file:///tmp/reset-password"),
                         "FOWOCO 비밀번호 재설정"
-                )
+                ),
+                mailProperties("smtp.fowoco.test", false, null, null)
         )).isInstanceOf(IllegalStateException.class)
                 .hasMessageContaining("PASSWORD_RESET_CLIENT_URL");
     }
+
+    @Test
+    void rejectsMissingHostAndAuthenticationCredentials() {
+        JavaMailSender mailSender = mock(JavaMailSender.class);
+        PasswordResetNotificationProperties notificationProperties =
+                new PasswordResetNotificationProperties(
+                        "no-reply@fowoco.test",
+                        URI.create("https://demo.fowoco.test/reset-password"),
+                        "FOWOCO 비밀번호 재설정"
+                );
+
+        assertThatThrownBy(() -> new SmtpPasswordResetNotificationAdapter(
+                mailSender,
+                notificationProperties,
+                mailProperties("", false, null, null)
+        )).isInstanceOf(IllegalStateException.class)
+                .hasMessageContaining("SPRING_MAIL_HOST");
+
+        assertThatThrownBy(() -> new SmtpPasswordResetNotificationAdapter(
+                mailSender,
+                notificationProperties,
+                mailProperties("smtp.fowoco.test", true, "", "password")
+        )).isInstanceOf(IllegalStateException.class)
+                .hasMessageContaining("SPRING_MAIL_USERNAME");
+
+        assertThatThrownBy(() -> new SmtpPasswordResetNotificationAdapter(
+                mailSender,
+                notificationProperties,
+                mailProperties("smtp.fowoco.test", true, "mailer", "")
+        )).isInstanceOf(IllegalStateException.class)
+                .hasMessageContaining("SPRING_MAIL_PASSWORD");
+    }
+
+    private MailProperties mailProperties(
+            String host,
+            boolean authenticationRequired,
+            String username,
+            String password
+    ) {
+        MailProperties properties = new MailProperties();
+        properties.setHost(host);
+        properties.setUsername(username);
+        properties.setPassword(password);
+        properties.getProperties().put("mail.smtp.auth", Boolean.toString(authenticationRequired));
+        return properties;
+    }
 }