fix-be: 이메일 인증 시 이미 가입된 이메일은 예외를 던지도록 변경

backend/src/docs/asciidoc/email.adoc

@@ -24,6 +24,10 @@ operation::email/verification-code[snippets="http-request,request-fields,http-re
 
 operation::email/verification-code-fail/invalid-email[snippets="http-request,request-fields,http-response"]
 
+==== 실패: 이미 가입된 이메일
+
+operation::email/verification-code-fail/already_signed_up[snippets="http-request,request-fields,http-response"]
+
 === 이메일 인증 확인
 
 ==== 성공

backend/src/main/java/com/cruru/email/exception/badrequest/EmailAlreadySignedUpException.java

@@ -0,0 +1,12 @@
+package com.cruru.email.exception.badrequest;
+
+import com.cruru.advice.badrequest.BadRequestException;
+
+public class EmailAlreadySignedUpException extends BadRequestException {
+
+    private static final String MESSAGE = "이미 가입된 이메일입니다.";
+
+    public EmailAlreadySignedUpException() {
+        super(MESSAGE);
+    }
+}

backend/src/main/java/com/cruru/email/facade/EmailFacade.java

@@ -8,10 +8,12 @@
 import com.cruru.email.controller.request.SendVerificationCodeRequest;
 import com.cruru.email.controller.request.VerifyCodeRequest;
 import com.cruru.email.exception.EmailAttachmentsException;
+import com.cruru.email.exception.badrequest.EmailAlreadySignedUpException;
 import com.cruru.email.service.EmailRedisClient;
 import com.cruru.email.service.EmailService;
 import com.cruru.email.util.FileUtil;
 import com.cruru.email.util.VerificationCodeUtil;
+import com.cruru.member.service.MemberService;
 import java.io.File;
 import java.io.IOException;
 import java.util.List;
@@ -27,6 +29,7 @@ public class EmailFacade {
     private final EmailService emailService;
     private final ClubService clubService;
     private final ApplicantService applicantService;
+    private final MemberService memberService;
     private final EmailRedisClient emailRedisClient;
 
     public void send(EmailRequest request) {
@@ -58,11 +61,17 @@ private List<File> saveTempFiles(Club from, String subject, List<MultipartFile>
     public void sendVerificationCode(SendVerificationCodeRequest request) {
         String email = request.email();
         String verificationCode = VerificationCodeUtil.generateVerificationCode();
-
+        validateEmailExists(email);
         emailRedisClient.saveVerificationCode(email, verificationCode);
         emailService.sendVerificationCode(email, verificationCode);
     }
 
+    private void validateEmailExists(String email) {
+        if (memberService.existsByEmail(email)) {
+            throw new EmailAlreadySignedUpException();
+        }
+    }
+
     public void verifyCode(VerifyCodeRequest request) {
         String email = request.email();
         String inputVerificationCode = request.verificationCode();

backend/src/main/java/com/cruru/member/service/MemberService.java

@@ -62,4 +62,8 @@ public Member findByEmail(String email) {
         return memberRepository.findByEmail(email)
                 .orElseThrow(MemberNotFoundException::new);
     }
+
+    public boolean existsByEmail(String email) {
+        return memberRepository.existsByEmail(email);
+    }
 }

backend/src/test/java/com/cruru/auth/controller/AuthControllerTest.java

@@ -1,5 +1,7 @@
 package com.cruru.auth.controller;
 
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.doNothing;
 import static org.springframework.restdocs.cookies.CookieDocumentation.cookieWithName;
 import static org.springframework.restdocs.cookies.CookieDocumentation.requestCookies;
 import static org.springframework.restdocs.cookies.CookieDocumentation.responseCookies;
@@ -11,6 +13,7 @@
 import static org.springframework.restdocs.restassured.RestAssuredRestDocumentation.document;
 
 import com.cruru.auth.controller.request.LoginRequest;
+import com.cruru.auth.service.TokenRedisClient;
 import com.cruru.club.domain.repository.ClubRepository;
 import com.cruru.member.domain.Member;
 import com.cruru.member.domain.repository.MemberRepository;
@@ -23,6 +26,7 @@
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.mock.mockito.MockBean;
 
 @DisplayName("인증 컨트롤러 테스트")
 class AuthControllerTest extends ControllerTest {
@@ -33,6 +37,9 @@ class AuthControllerTest extends ControllerTest {
     @Autowired
     private ClubRepository clubRepository;
 
+    @MockBean
+    private TokenRedisClient tokenRedisClient;
+
     private Member member;
 
     @BeforeEach
@@ -48,6 +55,7 @@ void setup() {
     void login() {
         // given
         LoginRequest request = new LoginRequest(member.getEmail(), "qwer1234");
+        doNothing().when(tokenRedisClient).saveToken(any(), any());
 
         // when&then
         RestAssured.given(spec).log().all()

backend/src/test/java/com/cruru/email/controller/EmailControllerTest.java

@@ -15,9 +15,11 @@
 import com.cruru.email.controller.request.SendVerificationCodeRequest;
 import com.cruru.email.controller.request.VerifyCodeRequest;
 import com.cruru.email.service.EmailRedisClient;
+import com.cruru.member.domain.repository.MemberRepository;
 import com.cruru.util.ControllerTest;
 import com.cruru.util.fixture.ApplicantFixture;
 import com.cruru.util.fixture.EmailFixture;
+import com.cruru.util.fixture.MemberFixture;
 import io.restassured.RestAssured;
 import io.restassured.http.ContentType;
 import java.io.File;
@@ -32,6 +34,9 @@ class EmailControllerTest extends ControllerTest {
     @Autowired
     private ApplicantRepository applicantRepository;
 
+    @Autowired
+    private MemberRepository memberRepository;
+
     @MockBean
     private EmailRedisClient emailRedisClient;
 
@@ -150,6 +155,25 @@ void sendVerificationCode() {
                 .then().log().all().statusCode(200);
     }
 
+    @DisplayName("이메일 인증 번호 발송 시, 이미 가입된 이메일일 경우 400을 응답한다.")
+    @Test
+    void sendVerificationCode_alreadySignedUp() {
+        // given
+        String email = MemberFixture.DOBBY.getEmail();
+        memberRepository.save(MemberFixture.DOBBY);
+        SendVerificationCodeRequest request = new SendVerificationCodeRequest(email);
+
+        // when & then
+        RestAssured.given(spec).log().all()
+                .contentType(ContentType.JSON)
+                .body(request)
+                .filter(document("email/verification-code-fail/already_signed_up",
+                        requestFields(fieldWithPath("email").description("이미 가입된 이메일"))
+                ))
+                .when().post("/v1/emails/verification-code")
+                .then().log().all().statusCode(400);
+    }
+
     @DisplayName("이메일 인증 번호 발송 시, 이메일 형식이 올바르지 않을 경우 400을 응답한다.")
     @Test
     void sendVerificationCode_invalidEmailFormat() {