fix(be): toggle like (#39)

* feat: add unique keys in like table

Co-authored-by: 유영재 <[email protected]>
Co-authored-by: shl0501 <[email protected]>

* fix: refactor like toggle logic

Co-authored-by: 유영재 <[email protected]>
Co-authored-by: shl0501 <[email protected]>

* test: update toggle like test mocking

Co-authored-by: 유영재 <[email protected]>
Co-authored-by: shl0501 <[email protected]>
---------

Co-authored-by: 유영재 <[email protected]>
Co-authored-by: shl0501 <[email protected]>

Author: 3 people

apps/server/prisma/migrations/20250122053033_unique_like/migration.sql

@@ -0,0 +1,12 @@
+/*
+  Warnings:
+
+  - A unique constraint covering the columns `[create_user_token,question_id]` on the table `QuestionLike` will be added. If there are existing duplicate values, this will fail.
+  - A unique constraint covering the columns `[create_user_token,reply_id]` on the table `ReplyLike` will be added. If there are existing duplicate values, this will fail.
+
+*/
+-- CreateIndex
+CREATE UNIQUE INDEX "QuestionLike_create_user_token_question_id_key" ON "QuestionLike"("create_user_token", "question_id");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "ReplyLike_create_user_token_reply_id_key" ON "ReplyLike"("create_user_token", "reply_id");

apps/server/prisma/migrations/20250122053355_add_like_index/migration.sql

@@ -0,0 +1,24 @@
+/*
+  Warnings:
+
+  - A unique constraint covering the columns `[question_id,create_user_token]` on the table `QuestionLike` will be added. If there are existing duplicate values, this will fail.
+  - A unique constraint covering the columns `[reply_id,create_user_token]` on the table `ReplyLike` will be added. If there are existing duplicate values, this will fail.
+
+*/
+-- DropIndex
+DROP INDEX "QuestionLike_create_user_token_question_id_key";
+
+-- DropIndex
+DROP INDEX "ReplyLike_create_user_token_reply_id_key";
+
+-- CreateIndex
+CREATE INDEX "QuestionLike_question_id_create_user_token_idx" ON "QuestionLike"("question_id", "create_user_token");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "QuestionLike_question_id_create_user_token_key" ON "QuestionLike"("question_id", "create_user_token");
+
+-- CreateIndex
+CREATE INDEX "ReplyLike_reply_id_create_user_token_idx" ON "ReplyLike"("reply_id", "create_user_token");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "ReplyLike_reply_id_create_user_token_key" ON "ReplyLike"("reply_id", "create_user_token");

apps/server/prisma/migrations/20250122053700_remove_like_index/migration.sql

@@ -0,0 +1,5 @@
+-- DropIndex
+DROP INDEX "QuestionLike_question_id_create_user_token_idx";
+
+-- DropIndex
+DROP INDEX "ReplyLike_reply_id_create_user_token_idx";

apps/server/prisma/schema.prisma

@@ -93,6 +93,8 @@ model QuestionLike {
 
   question              Question         @relation("QuestionLikes", fields: [questionId], references: [questionId], onDelete: Cascade)
   createUserTokenEntity UserSessionToken @relation("TokenQuestionLikes", fields: [createUserToken], references: [token])
+
+  @@unique([questionId, createUserToken])
 }
 
 model Reply {
@@ -117,6 +119,8 @@ model ReplyLike {
 
   reply                 Reply            @relation("ReplyLikes", fields: [replyId], references: [replyId], onDelete: Cascade)
   createUserTokenEntity UserSessionToken @relation("TokenReplyLikes", fields: [createUserToken], references: [token])
+
+  @@unique([replyId, createUserToken])
 }
 
 model Chatting {

apps/server/src/questions/questions.repository.ts

@@ -124,9 +124,12 @@ export class QuestionsRepository {
     });
   }
 
-  async deleteLike(questionLikeId: number) {
-    await this.prisma.questionLike.delete({
-      where: { questionLikeId },
+  async deleteLike(questionId: number, createUserToken: string) {
+    await this.prisma.questionLike.deleteMany({
+      where: {
+        questionId,
+        createUserToken,
+      },
     });
   }
 

apps/server/src/questions/questions.service.spec.ts

@@ -1,5 +1,6 @@
 import { ForbiddenException } from '@nestjs/common';
 import { Test, TestingModule } from '@nestjs/testing';
+import { PrismaClientKnownRequestError } from '@prisma/client/runtime/library';
 
 import { QuestionsRepository } from './questions.repository';
 import { QuestionsService } from './questions.service';
@@ -198,24 +199,24 @@ describe('QuestionsService', () => {
 
   describe('toggleLike', () => {
     it('좋아요가 없을 경우 생성하고 liked: true를 반환해야 한다', async () => {
-      questionsRepository.findLike.mockResolvedValue(null);
-
       const result = await service.toggleLike(1, 'test-token');
 
       expect(questionsRepository.createLike).toHaveBeenCalledWith(1, 'test-token');
       expect(result).toEqual({ liked: true });
     });
 
     it('이미 좋아요가 있을 경우 삭제하고 liked: false를 반환해야 한다', async () => {
-      questionsRepository.findLike.mockResolvedValue({
-        questionLikeId: 1,
-        createUserToken: 'test-token',
-        questionId: 1,
-      });
+      questionsRepository.createLike.mockRejectedValueOnce(
+        new PrismaClientKnownRequestError('Unique constraint violation', {
+          code: 'P2002',
+          clientVersion: '2.x.x',
+        }),
+      );
 
       const result = await service.toggleLike(1, 'test-token');
 
-      expect(questionsRepository.deleteLike).toHaveBeenCalledWith(1);
+      expect(questionsRepository.createLike).toHaveBeenCalledWith(1, 'test-token');
+      expect(questionsRepository.deleteLike).toHaveBeenCalledWith(1, 'test-token');
       expect(result).toEqual({ liked: false });
     });
   });

apps/server/src/questions/questions.service.ts

@@ -1,5 +1,6 @@
 import { ForbiddenException, Injectable, NotFoundException } from '@nestjs/common';
 import { Question } from '@prisma/client';
+import { PrismaClientKnownRequestError } from '@prisma/client/runtime/library';
 
 import { CreateQuestionDto } from './dto/create-question.dto';
 import { GetQuestionDto } from './dto/get-question.dto';
@@ -15,6 +16,7 @@ import {
 import { RepliesRepository } from '@replies/replies.repository';
 import { SessionsRepository } from '@sessions/sessions.repository';
 import { SessionsAuthRepository } from '@sessions-auth/sessions-auth.repository';
+import { PRISMA_ERROR_CODE } from '@src/prisma/prisma.error';
 
 @Injectable()
 export class QuestionsService {
@@ -172,10 +174,19 @@ export class QuestionsService {
   }
 
   async toggleLike(questionId: number, createUserToken: string) {
-    const exist = await this.questionRepository.findLike(questionId, createUserToken);
-    if (exist) await this.questionRepository.deleteLike(exist.questionLikeId);
-    else await this.questionRepository.createLike(questionId, createUserToken);
-    return { liked: !exist };
+    try {
+      await this.questionRepository.createLike(questionId, createUserToken);
+      return { liked: true };
+    } catch (error) {
+      if (
+        error instanceof PrismaClientKnownRequestError &&
+        error.code === PRISMA_ERROR_CODE.UNIQUE_CONSTRAINT_VIOLATION
+      ) {
+        await this.questionRepository.deleteLike(questionId, createUserToken);
+        return { liked: false };
+      }
+      throw error;
+    }
   }
 
   async getLikesCount(questionId: number) {