[FEAT] 크루 탈퇴 API 개발

src/main/java/com/genius/herewe/business/crew/controller/CrewController.java

@@ -43,7 +43,7 @@ public class CrewController implements CrewApi {
 
 	@GetMapping("/profile/{crewId}")
 	public SingleResponse<CrewProfileResponse> inquiryCrewProfile(@HereWeUser User user,
-		@PathVariable Long crewId) {
+																  @PathVariable Long crewId) {
 		CrewProfileResponse crewProfileResponse = crewFacade.inquiryCrewProfile(user.getId(), crewId);
 		return new SingleResponse<>(HttpStatus.OK, crewProfileResponse);
 	}
@@ -126,4 +126,11 @@ public CommonResponse expelCrew(
 
 		return CommonResponse.ok();
 	}
+
+	@DeleteMapping("/{crewId}/members/me")
+	public CommonResponse quitCrew(@HereWeUser User user,
+								   @PathVariable Long crewId) {
+		crewFacade.quitCrew(user.getId(), crewId);
+		return CommonResponse.ok();
+	}
 }

src/main/java/com/genius/herewe/business/crew/facade/CrewFacade.java

@@ -27,4 +27,6 @@ public interface CrewFacade {
 	void deleteCrew(Long crewId);
 
 	void expelCrew(Long userId, CrewExpelRequest expelRequest);
+
+	void quitCrew(Long userId, Long crewId);
 }

src/main/java/com/genius/herewe/business/crew/facade/DefaultCrewFacade.java

@@ -125,4 +125,19 @@ public void expelCrew(Long userId, CrewExpelRequest expelRequest) {
 		crewMemberService.delete(crewMember);
 		crew.updateParticipantCount(-1);
 	}
+
+	@Override
+	@Transactional
+	public void quitCrew(Long userId, Long crewId) {
+		User user = userService.findById(userId);
+		Crew crew = crewService.findById(crewId);
+
+		CrewMember crewMember = crewMemberService.find(userId, crewId);
+		if (crewMember.getRole() == CrewRole.LEADER) {
+			throw new BusinessException(LEADER_CANNOT_EXPEL);
+		}
+
+		crewMemberService.delete(crewMember);
+		crew.updateParticipantCount(-1);
+	}
 }