Fixes #525: Add eslint-plugin-promise and fix async/Promise issues

.eslintrc.js

@@ -1,6 +1,6 @@
 module.exports = {
-  extends: ['airbnb-base', 'prettier'],
-  plugins: ['prettier'],
+  extends: ['airbnb-base', 'prettier', 'plugin:promise/recommended'],
+  plugins: ['prettier', 'promise'],
   env: {
     jest: true,
     browser: true,
@@ -23,6 +23,36 @@ module.exports = {
      */
     'no-param-reassign': ['error', { props: false }],
 
+    /**Disallows unnecessary return await
+     * https://eslint.org/docs/rules/no-return-await
+     */
+    'no-return-await': ['error'],
+
+    /**
+     * Disallow using an async function as a Promise executor
+     * https://eslint.org/docs/rules/no-async-promise-executor
+     */
+    'no-async-promise-executor': ['error'],
+
+    /**
+     * Disallow await inside of loops
+     * https://eslint.org/docs/rules/no-await-in-loop
+     */
+    'no-await-in-loop': ['error'],
+
+    /**
+     * Disallow assignments that can lead to race conditions due to
+     * usage of await or yield
+     * https://eslint.org/docs/rules/require-atomic-updates
+     */
+    'require-atomic-updates': ['error'],
+
+    /**
+     * Disallow async functions which have no await expression
+     * https://eslint.org/docs/rules/require-await
+     */
+    'require-await': ['error'],
+
     /**
      * Require or disallow named function expressions
      * https://eslint.org/docs/rules/func-names
@@ -34,5 +64,20 @@ module.exports = {
      * https://eslint.org/docs/rules/func-names
      */
     'linebreak-style': 'off',
+
+    /**
+     * The following are eslint rules from the promise-plugin
+     * https://github.com/xjamundx/eslint-plugin-promise
+     */
+
+    /**
+     * Prefer wait to then() for reading Promise values
+     */
+    'promise/prefer-await-to-then': 'warn',
+
+    /**
+     * Prefer async/await to the callback pattern
+     */
+    'promise/prefer-await-to-callbacks': 'warn',
   },
 };

package.json

@@ -91,6 +91,7 @@
     "eslint-config-prettier": "6.7.0",
     "eslint-plugin-import": "2.18.2",
     "eslint-plugin-prettier": "3.1.1",
+    "eslint-plugin-promise": "4.2.1",
     "hint": "6.0.0",
     "husky": "3.1.0",
     "jest": "24.9.0",

src/backend/feed/queue.js

@@ -30,7 +30,7 @@ queue.addFeed = async function(feedInfo) {
   };
 
   try {
-    queue.add(feedInfo, options);
+    await queue.add(feedInfo, options);
   } catch (err) {
     logger.error({ err, feedInfo }, 'Unable to add job to queue');
   }

src/backend/utils/basic_analysis.js

@@ -71,18 +71,8 @@ module.exports = function analyzeText(text_) {
 
   // asynchonize function
   // to get a basic analysis information, getAsyAnalysis should be called
-  this.getAsyAnalysis = async function() {
-    return new Promise((res, rej) => {
-      if (isValidString) {
-        res(analysis);
-      } else {
-        res(textInfo);
-      }
-      if (isValidString === undefined) {
-        rej(textInfo);
-      }
-    });
+  this.getAsyAnalysis = function() {
+    return isValidString ? analysis : textInfo;
   };
-
   return this;
 };

src/backend/utils/email-sender.js

@@ -2,8 +2,6 @@ require('../lib/config');
 const nodemailer = require('nodemailer');
 const { logger } = require('./logger');
 
-const log = logger.child({ module: 'email-sender' });
-
 /*
                              HOW TO USE
  Import this file - const sendEmail = require('./email-sender);
@@ -69,39 +67,36 @@ exports.verifyTransporter = function(transporter) {
   transporter.verify(err => {
     // If error then print to console
     if (err) {
-      log.error({ err }, 'Transporter connection failed.');
+      logger.error({ err }, 'Transporter connection failed.');
       return false;
     }
     // else print a ready message
-    log.info('Server is running properly');
+    logger.info('Server is running properly');
     return true;
   });
 };
 
 // Sends a message using the passed in parameters
 exports.sendMessage = async function(receipiants, subjectMessage, message) {
-  return new Promise((resolve, reject) => {
-    const transporter = this.createTransporter(
+  try {
+    const transporter = await this.createTransporter(
       process.env.NODEMAILER_SERVER,
       2222,
       false,
       process.env.NODEMAILER_USERNAME,
       process.env.NODEMAILER_PASSWORD
     );
-    const allGood = this.verifyTransporter(transporter);
-    if (!allGood) {
-      reject(new Error()); // Send promise.reject if an error occurs
+    if (!this.verifyTransporter(transporter)) {
+      throw new Error('Email transport could not be verified');
     }
     // Creates email for to be sent
     const mail = this.createMail(receipiants, subjectMessage, message);
 
     // Send the email with the email content
-    transporter.sendMail(mail, (err, info) => {
-      if (err) {
-        reject(err); // Send promise.reject if an error occurs
-      } else {
-        resolve(info.accepted); // Send promise.resolve if an error occurs
-      }
-    });
-  });
+    const result = await transporter.sendMail(mail);
+    return result.accepted;
+  } catch (error) {
+    logger.error({ error }, 'Unable to send email');
+    throw error;
+  }
 };

src/backend/utils/github-url.js

@@ -1,6 +1,7 @@
 require('../lib/config');
 const parseGithubUrl = require('parse-github-url');
 const fetch = require('node-fetch');
+const { logger } = require('./logger');
 
 const githubAPI = 'http://api.github.com';
 
@@ -56,69 +57,71 @@ exports.getGithubUrlData = async incomingUrl => {
     typeof process.env.GITHUB_TOKEN !== 'undefined'
       ? `?access_token=${process.env.GITHUB_TOKEN}`
       : '';
+  let data;
+  try {
+    const fetchResult = await fetch(`${githubAPI}${subUrl}`);
+    data = await fetchResult.json();
+  } catch (error) {
+    logger.error({ error }, 'Unable to fetch GitHub API results');
+    throw error;
+  }
+  let fetchedData;
+  /**
+   * Format the fetched data in a specifi way depending if the url
+   * is for a repo, user or for a {pull request, issue}
+   */
+  // User
+  if (ghUrl.repo === null) {
+    const { login: user, avatar_url: avatarURL, name, company, blog, email, bio } = data;
 
-  return fetch(`${githubAPI}${subUrl}`)
-    .then(res => res.json())
-    .then(data => {
-      let fetchedData;
-
-      /**
-       * Format the fetched data in a specifi way depending if the url
-       * is for a repo, user or for a {pull request, issue}
-       */
-      // User
-      if (ghUrl.repo === null) {
-        const { login: user, avatar_url: avatarURL, name, company, blog, email, bio } = data;
-
-        fetchedData = {
-          user,
-          avatarURL,
-          name,
-          company,
-          blog,
-          email,
-          bio,
-        };
+    fetchedData = {
+      user,
+      avatarURL,
+      name,
+      company,
+      blog,
+      email,
+      bio,
+    };
 
-        // Repo
-      } else if (ghUrl.branch === 'master') {
-        const {
-          owner: { avatar_url: avatarURL },
-          description,
-          license,
-          open_issues: openIssues,
-          forks,
-          created_at: createdAt,
-          language,
-        } = data;
+    // Repo
+  } else if (ghUrl.branch === 'master') {
+    const {
+      owner: { avatar_url: avatarURL },
+      description,
+      license,
+      open_issues: openIssues,
+      forks,
+      created_at: createdAt,
+      language,
+    } = data;
 
-        fetchedData = {
-          avatarURL,
-          description,
-          license,
-          openIssues,
-          forks,
-          createdAt,
-          language,
-        };
+    fetchedData = {
+      avatarURL,
+      description,
+      license,
+      openIssues,
+      forks,
+      createdAt,
+      language,
+    };
 
-        // Issue or Pull Request
-      } else {
-        const {
-          user: { login, avatar_url: avatarURL },
-          body,
-          created_at: createdAt,
-        } = data;
+    // Issue or Pull Request
+  } else {
+    const {
+      user: { login, avatar_url: avatarURL },
+      body,
+      created_at: createdAt,
+    } = data;
 
-        fetchedData = {
-          login,
-          avatarURL,
-          body,
-          createdAt,
-          branch: ghUrl.branch,
-          repo: ghUrl.name,
-        };
-      }
-      return fetchedData;
-    });
+    fetchedData = {
+      login,
+      avatarURL,
+      body,
+      createdAt,
+      branch: ghUrl.branch,
+      repo: ghUrl.name,
+    };
+  }
+  return fetchedData;
 };