ft(paginate-article): Add pagination support for articles

- Write unit tests
- Allow pagination for articles using query
- Validate the query parameter

[Delivers #159206061]

.gitignore

@@ -41,3 +41,6 @@ dist/
 
 #txt
 txt.txt
+
+#VS Code
+.vscode

controllers/ArticleController.js

@@ -1,14 +1,9 @@
-<<<<<<< HEAD
 import cloudinary from '../config/cloudinary';
-=======
-import cloudinary from 'cloudinary';
->>>>>>> ft(create-article): create user article
 import Utilities from '../helpers/utilities';
 import { Article, User } from '../models';
 import createArticleHelper from '../helpers/createArticleHelper';
 
 /**
-<<<<<<< HEAD
  * Article class for users
  * @param {method} createArticle - Create article
  * @param {method} getArticle - Get a single article
@@ -24,76 +19,37 @@ class ArticleController {
   static createArticle(req, res) {
     const {
       title, description, body, tagList, imageData,
-=======
-     * Article class for users
-     * @param {method} createArticle - Create article
-     * @param {method} getArticle - Get a single article
-     * @param {method} editArticle update a single article
-    */
-class ArticleController {
-  /**
-     * Create an article for a user
-     * @param {object} req - The request object
-     * @param {object} res - The response object sent to user
-     * @return {object} A object containing created articles.
-     */
-  static createArticle(req, res) {
-    const {
-      title, description, body, tagList, imageUrl,
->>>>>>> ft(create-article): create user article
     } = req.body.article;
 
     const { userId } = req;
 
     const articleObject = {
-<<<<<<< HEAD
       title, description, body, tagList, imageData, userId
-=======
-      title, description, body, tagList, imageUrl, userId
->>>>>>> ft(create-article): create user article
     };
     /**
      * check if image was provided in the request
      * upload the image to cloudinary, save the article
      * with the cloudinary URL in database but if an error
      * was encountered from cloudinary go ahead and create the article
-<<<<<<< HEAD
     */
     if (imageData) {
       return cloudinary.v2.uploader.upload(imageData, { tags: 'basic_sample' })
-=======
-     */
-    if (imageUrl) {
-      return cloudinary.v2.uploader.upload(imageUrl, { tags: 'basic_sample' })
->>>>>>> ft(create-article): create user article
         .then(image => createArticleHelper(res, articleObject, image.url))
         .catch(() => createArticleHelper(res, articleObject));
     }
 
-<<<<<<< HEAD
     // if there no image was provided go ahead to create the article
-=======
-    /**
-     * if there no image was provided go ahead to create the article
-    */
->>>>>>> ft(create-article): create user article
     return createArticleHelper(res, articleObject);
   }
 
   /**
    * get an article using slug as query parameter
    * @param {object} req - request object
    * @param {object} res - response object
-<<<<<<< HEAD
    * @param {function} next - next function
    * @returns {object} - the found article from database or error if not found
   */
   static getArticle(req, res, next) {
-=======
-   * @returns {object} - the found article from database or error if not found
-   */
-  static getArticle(req, res) {
->>>>>>> ft(create-article): create user article
     const { slug } = req.params;
 
     return Article
@@ -103,17 +59,9 @@ class ArticleController {
           model: User,
           attributes: { exclude: ['id', 'email', 'hashedPassword', 'createdAt', 'updatedAt'] }
         }],
-<<<<<<< HEAD
-        attributes: { exclude: ['userId'] }
       })
       .then((article) => {
         // if the article does not exist
-=======
-        attributes: { exclude: ['id', 'userId'] }
-      })
-      .then((article) => {
-        /** if the article does not exist */
->>>>>>> ft(create-article): create user article
         if (!article) {
           return res.status(404).json({
             errors: {
@@ -126,57 +74,53 @@ class ArticleController {
 
         return res.status(200).json({ article });
       })
-<<<<<<< HEAD
       .catch(next);
-=======
-      .catch(() => res.status(501).send('oops  seems there is an error find the article'));
->>>>>>> ft(create-article): create user article
   }
 
   /**
-   * get all articles created
+   * get all articles created and use the query
+   * if provided to implement pagination
    * @param {object} req - request object
    * @param {object} res - response object
-<<<<<<< HEAD
    * @param {function} next - next function
    * @returns {object} - the found article from database or empty if not found
   */
   static listAllArticles(req, res, next) {
-=======
-   * @returns {object} - the found article from database or empty if not found
-   */
-  static listAllArticles(req, res) {
->>>>>>> ft(create-article): create user article
+    const { page, limit } = req;
+    let offset = null;
+
+    if (page || limit) {
+      // calculate offset
+      offset = limit * (page - 1);
+    }
+
     return Article
       .findAll({
         include: [{
           model: User,
           attributes: { exclude: ['id', 'email', 'hashedPassword', 'createdAt', 'updatedAt'] }
         }],
-<<<<<<< HEAD
-        attributes: { exclude: ['userId'] }
+        offset,
+        limit,
       })
       .then((articles) => {
-        // check if there was no article created
         if (articles.length === 0) {
+        /** check if there was no article created
+         *  for the page query
+        */
+          const message = page ? 'articles limit exceeded'
+            : 'Sorry, no articles created';
           return res.status(200).json({
-            message: 'No articles created',
-=======
-        attributes: { exclude: ['id', 'userId'] }
-      })
-      .then((articles) => {
-        /** check if there was no article created */
-        if (articles.length === 0) {
-          return res.status(200).json({
-            message: 'Your request was successful but no articles created',
->>>>>>> ft(create-article): create user article
+            message,
             articles,
+            articlesCount: articles.length
           });
         }
-
-        return res.status(200).json({ articles, articlesCount: articles.length });
+        return res.status(200).json({
+          articles,
+          articlesCount: articles.length
+        });
       })
-<<<<<<< HEAD
       .catch(next);
   }
 
@@ -186,26 +130,11 @@ class ArticleController {
   * @param {object} req: request object
   * @param {object} res: response object
   * @param {function} next - next function
-=======
-      .catch(() => res.status(501).send('oops  seems there is an error find all articles'));
-  }
-
-  /**
-   * @function editArticle
-  * @summary: API controller to handle requests
-  * to edit an article
-  * @param {object} req: request object
-  * @param {object} res: response object
->>>>>>> ft(create-article): create user article
   * @returns {object} api response: article object for
   * successful requests, or error object for
   * requests that fail
   */
-<<<<<<< HEAD
   static editArticle(req, res, next) {
-=======
-  static editArticle(req, res) {
->>>>>>> ft(create-article): create user article
     const { title, description, body } = req.body.article;
     const { count } = req;
     const { slug } = req.params;
@@ -225,7 +154,6 @@ class ArticleController {
         success: true,
         article: result[1]
       }))
-<<<<<<< HEAD
       .catch(next);
   }
 
@@ -239,50 +167,12 @@ class ArticleController {
   * successful requests, or error object for requests that fail
   */
   static deleteArticle(req, res, next) {
-=======
-      .catch((err) => {
-        res.status(500).json({
-          errors: {
-            body: [
-              'sorry there was an error updating this request',
-              err
-            ]
-          }
-        });
-      });
-  }
-
-  /**
- * @function deleteArticle
-* @summary: API controller to handle requests
-* to delete an article
-* @param {object} req: request object
-* @param {object} res: response object
-* @returns {object} api response: article object for
-* successful requests, or error object for
-* requests that fail
-*/
-  static deleteArticle(req, res) {
->>>>>>> ft(create-article): create user article
     const { slug } = req.params;
     Article.destroy({
       where: { slug }
     })
-<<<<<<< HEAD
       .then(() => res.status(200).json({ message: 'Article successfully deleted' }))
       .catch(next);
-=======
-      .then(() => res.status(204).json())
-      .catch(() => {
-        res.status(500).json({
-          errors: {
-            body: [
-              'sorry there was an error deleting this request',
-            ]
-          }
-        });
-      });
->>>>>>> ft(create-article): create user article
   }
 }
 

helpers/createArticleHelper.js

@@ -30,7 +30,6 @@ const createArticleHelper = (res, articleObject, imageUrl = null) => {
         model: User,
         attributes: { exclude: ['id', 'email', 'hashedPassword', 'createdAt', 'updatedAt'] }
       }],
-      attributes: { exclude: ['userId'] }
     }))
     .then(article => res.status(201).json({ article }));
 };

middlewares/ParamsValidator.js

@@ -41,4 +41,25 @@ export default class ParamsValidator {
     }
     next();
   }
+
+  /**
+   * Checks the  page params provided for integer 1 and above
+   *  and assign a default value when less than 1
+   * @param {string} req - The request to be validated
+   * @param {string} res - The response from validation
+   * @param {string} next - The next function
+   * @returns {undefined}
+   */
+  static validatePageQuery(req, res, next) {
+    let { page, limit } = req.query;
+
+    if (page || limit) {
+      page = Number(page);
+      limit = Number(limit);
+
+      req.page = (page < 1 || !Number.isInteger(page)) ? 1 : page;
+      req.limit = (limit < 1 || !Number.isInteger(limit)) ? 10 : limit;
+    }
+    next();
+  }
 }