course exist error

backend/src/controllers/course.js

@@ -6,7 +6,10 @@ const {
   handleRequestWithInternalServerError
 } = require('../util/common');
 
-const { NotExistError } = require('../util/error');
+const {
+  NotExistError,
+  CourseExistError
+} = require('../util/error');
 
 const {
   createCourse,
@@ -55,6 +58,8 @@ exports.createCourseData = async (req, res) => {
   } catch (error) {
     if (error instanceof NotExistError) {
       handleRequestWithResourceItemNotFound(res, error);
+    } else if (error instanceof CourseExistError) {
+      handleRequestWithInvalidRequestBody(res, error);
     } else {
       handleRequestWithInternalServerError(res, error);
     }
@@ -68,6 +73,10 @@ exports.updateCourseData = async (req, res) => {
     const updatedCourse = await updateCourse(course, changeset);
     res.json(updatedCourse);
   } catch (error) {
-    handleRequestWithInternalServerError(res, error);
+    if (error instanceof CourseExistError) {
+      handleRequestWithInvalidRequestBody(res, error);
+    } else {
+      handleRequestWithInternalServerError(res, error);
+    }
   }
 };

backend/src/hooks/course.js

+const { Course } = require('../models/index');
+
+const {
+  checkCourseExist
+} = require('../util/hook');
+
+Course.beforeCreate(async (course) => {
+  await checkCourseExist(course, true);
+});
+
+Course.beforeUpdate(async (course) => {
+  await checkCourseExist(course, false);
+});
\ No newline at end of file

backend/src/index.js

@@ -22,6 +22,7 @@ const optionRouter = require('./routes/option');
 
 require('./hooks/study-plan');
 require('./hooks/course-class');
+require('./hooks/course');
 
 app.use(cors());
 app.use(express.json());

backend/src/util/error.js

@@ -42,12 +42,19 @@ class StudyPlanExistError extends Error {
   }
 }
 
+class CourseExistError extends Error {
+  constructor() {
+    super("Course's already exist");
+  }
+}
+
 class LecturerNotFoundError extends NotExistError {
   constructor() {
     super('Lecturer not found!');
   }
 }
 
+
 module.exports = {
   PasswordDoesntMatchError,
   EmailNotFoundError,
@@ -57,4 +64,5 @@ module.exports = {
   RequiredParameterUndefinedError,
   StudyPlanExistError,
   LecturerNotFoundError,
+  CourseExistError
 };

backend/src/util/hook.js

@@ -12,6 +12,7 @@ const { CourseClassStatusEnum } = require('../enums/index');
 
 const {
   ClassUnavailableError,
+  CourseExistError
 } = require('./error');
 
 const calculateTotalCredits = async (studyPlanCourses) => {
@@ -84,9 +85,24 @@ const checkClassAvailability = async (semester, startYear, courses) => {
   }
 };
 
+const checkCourseExist = async (course, isCreate) => {
+
+  const foundCourse = await Course.findOne({
+    where: {
+      code: course.code,
+      curriculumYear: course.curriculumYear
+    },
+  });
+
+  if (isCreate && foundCourse) throw new CourseExistError();
+
+  if (!isCreate && foundCourse.id !== course.id) throw new CourseExistError();
+};
+
 module.exports = {
   calculateTotalCredits,
   deleteCurrentMeetings,
   deleteCurrentMeetingAttendances,
-  checkClassAvailability
+  checkClassAvailability,
+  checkCourseExist
 };