[FIX] 방 나갈 때 쿠키 삭제 추가

backend/src/docs/asciidoc/room.adoc

@@ -98,6 +98,10 @@ include::{snippets}/room/leave/path-parameters.adoc[]
 
 include::{snippets}/room/leave/http-response.adoc[]
 
+response cookies
+
+include::{snippets}/room/leave/response-cookies.adoc[]
+
 '''
 
 === 방 설정 변경

backend/src/main/java/ddangkong/controller/room/RoomController.java

@@ -83,8 +83,10 @@ public RoomJoinResponse joinRoom(@PathVariable String uuid,
     @ResponseStatus(HttpStatus.NO_CONTENT)
     @DeleteMapping("/balances/rooms/{roomId}/members/{memberId}")
     public void leaveRoom(@PathVariable @Positive Long roomId,
-                          @PathVariable @Positive Long memberId) {
+                          @PathVariable @Positive Long memberId,
+                          HttpServletResponse response) {
         roomFacade.leaveRoom(roomId, memberId);
+        deleteCookie(response);
     }
 
     @ResponseStatus(HttpStatus.NO_CONTENT)
@@ -130,4 +132,9 @@ private void setEncryptCookie(HttpServletRequest request,
         ResponseCookie encodedCookie = roomMemberCookieEncryptor.getEncodedCookie(cookieValue, origin);
         response.addHeader(HttpHeaders.SET_COOKIE, encodedCookie.toString());
     }
+
+    private void deleteCookie(HttpServletResponse response) {
+        ResponseCookie deleteCookie = roomMemberCookieEncryptor.deleteCookie();
+        response.addHeader(HttpHeaders.SET_COOKIE, deleteCookie.toString());
+    }
 }

backend/src/main/java/ddangkong/controller/room/RoomMemberCookieEncryptor.java

@@ -1,6 +1,5 @@
 package ddangkong.controller.room;
 
-import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.web.server.Cookie.SameSite;
 import org.springframework.http.ResponseCookie;
@@ -9,6 +8,7 @@
 @Component
 public class RoomMemberCookieEncryptor {
 
+    private static final String ROOT_PATH = "/";
     private static final String DEFAULT_PATH = "/api/balances/rooms";
     private static final String LOCALHOST = "http://localhost";
 
@@ -31,6 +31,15 @@ public ResponseCookie getEncodedCookie(Object value, String origin) {
                 .build();
     }
 
+    public ResponseCookie deleteCookie() {
+        return ResponseCookie.from(rejoinKey, null)
+                .httpOnly(true)
+                .secure(true)
+                .path(ROOT_PATH)
+                .maxAge(0)
+                .build();
+    }
+
     private String getSameSiteOption(String origin) {
         if (origin != null && origin.startsWith(LOCALHOST)) {
             return SameSite.NONE.attributeValue();

backend/src/test/java/ddangkong/controller/room/RoomControllerTest.java

@@ -1,6 +1,7 @@
 package ddangkong.controller.room;
 
 import static ddangkong.support.fixture.MemberFixture.PRIN;
+import static org.assertj.core.api.Assertions.*;
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertAll;
 
@@ -370,5 +371,34 @@ class 쿠키 {
             // then
             assertThat(body.nickname()).isEqualTo(roomJoinResponse.member().nickname());
         }
+
+        @Test
+        void 방을_나가면_쿠키를_삭제한다() {
+            // given
+            RoomJoinRequest body = new RoomJoinRequest("참가자");
+            String cookie = RestAssured.given().log().all()
+                    .contentType(ContentType.JSON)
+                    .body(body)
+                    .when().post("/api/balances/rooms")
+                    .getCookie("test_cookie");
+
+            RoomJoinResponse roomJoinResponse = RestAssured.given().log().all()
+                    .contentType(ContentType.JSON)
+                    .cookie("test_cookie", cookie)
+                    .when().get("/api/balances/rooms/member")
+                    .then().contentType(ContentType.JSON).log().all()
+                    .statusCode(200)
+                    .extract().as(RoomJoinResponse.class);
+
+            // when
+            String deleteCookie = RestAssured.given().log().all()
+                    .pathParam("roomId", roomJoinResponse.roomId())
+                    .pathParam("memberId", roomJoinResponse.member().memberId())
+                    .cookie("test_cookie", cookie)
+                    .when().delete("/api/balances/rooms/{roomId}/members/{memberId}")
+                    .getCookie("test_cookie");
+
+            assertThat(deleteCookie).isBlank();
+        }
     }
 }

backend/src/test/java/ddangkong/documentation/room/RoomDocumentationTest.java

@@ -271,6 +271,9 @@ class 방_나가기 {
                             pathParameters(
                                     parameterWithName("roomId").description("방 ID"),
                                     parameterWithName("memberId").description("멤버 ID")
+                            ),
+                            responseCookies(
+                                    cookieWithName("test_cookie").description("삭제 쿠키")
                             )
                     ));
         }