164796907-feature(user-read-stats): refactor code

Remove unnecessary util functions and tests
Simplify feature

[#164796907]

src/controllers/article.js

@@ -16,8 +16,7 @@ import {
   omitProps,
   sendResponse,
   handleDBErrors,
-  addArticleToReadHistory,
-  removeDuplicateObject
+  addArticleToReadHistory
 } from '../utils';
 import { findAndCount } from '../utils/query';
 
@@ -345,13 +344,8 @@ export const getReadingStats = async (req, res) => {
       }],
       attributes: { exclude: ['createdAt', 'updatedAt'] }
     });
-    let readArticles = userReadHistory
-      .map(history => history.article)
-      .map(article => article.get({ plain: 'true' }));
 
-    // By stripping out duplicate articles
-    // we will return accurate article read statistics of this user
-    readArticles = removeDuplicateObject(readArticles, 'id');
+    const readArticles = userReadHistory.map(history => history.article);
 
     return res.status(200).json({
       status: 'success',

src/utils/index.js

@@ -180,28 +180,13 @@ export const handleDBErrors = (error, { req, Sequelize }, cb) => {
  */
 export const addArticleToReadHistory = async (articleId, userId) => {
   try {
-    const articleReadHistory = await ArticleReadHistory.create({ articleId, userId });
+    let articleReadHistory = await ArticleReadHistory.findOne({ where: { articleId, userId } });
+    if (!articleReadHistory) {
+      articleReadHistory = await ArticleReadHistory.create({ articleId, userId });
+      return articleReadHistory;
+    }
     return articleReadHistory;
   } catch (error) {
     throw error;
   }
 };
-
-/**
- * @description Removes duplicated object using attribute `prop`
- * @function removeDuplicateObject
- * @param {Array} array array of objects
- * @param {String} prop the prop to use as the criteria for uniqueness
- * @returns {Array} Returns an array of non-duplicated records (non-duplicated by `prop`)
- */
-export const removeDuplicateObject = (array, prop) => {
-  const arrayOfUniqs = [], uniq = {};
-  array.forEach((obj) => {
-    uniq[obj[prop]] = obj;
-  });
-  for (const entry of Object.entries(uniq)) {
-    const [, value] = entry;
-    arrayOfUniqs.push(value);
-  }
-  return arrayOfUniqs;
-};

tests/unit/util.test.js

@@ -4,8 +4,7 @@ import {
   errorResponseFormat,
   generateDummyWords,
   handleDBErrors,
-  checkIDParamType,
-  removeDuplicateObject
+  checkIDParamType
 } from '../../src/utils';
 import { invalidArticleUUID } from '../mock/bookmark';
 
@@ -90,16 +89,4 @@ describe('Util test', () => {
       });
     });
   });
-
-  describe('remove duplicated records', () => {
-    it('should remove duplicated objects from array', () => {
-      const dicts = [{ id: 1 }, { id: 3 }, { id: 1 }];
-      removeDuplicateObject(dicts, 'id').should.deep.equal([{ id: 1 }, { id: 3 }]);
-    });
-
-    it('should remove duplicated objects from array', () => {
-      const dicts = [{ id: 1 }, { id: 2 }, { id: 2 }];
-      removeDuplicateObject(dicts, 'id').should.deep.equal([{ id: 1 }, { id: 2 }]);
-    });
-  });
 });