created migration to brypt existing passwords

migrations/UpdateUserPasswords5.js

@@ -0,0 +1,46 @@
+const db = require('../models');
+const bcrypt = require('bcrypt');
+const logger = require('winston');
+
+module.exports = {
+  up: (queryInterface, Sequelize) => {
+    // get all the users
+    return db.User
+        .findAll()
+        .then((users) => {
+          // create an array of promises, with each promise bcrypting a password and updating the record
+          const promises = users.map((record) => {
+            // bcrypt
+            // generate a salt string to use for hashing
+            return new Promise((resolve, reject) => {
+              bcrypt.genSalt((saltError, salt) => {
+                if (saltError) {
+                  logger.error('salt error', saltError);
+                  reject(saltError);
+                  return;
+                }
+                // generate a hashed version of the user's password
+                bcrypt.hash(record.password, salt, (hashError, hash) => {
+                  // if there is an error with the hash generation return the error
+                  if (hashError) {
+                    logger.error('hash error', hashError);
+                    reject(hashError);
+                    return;
+                  }
+                  // replace the password string with the hash password value
+                  resolve(queryInterface.sequelize.query(`UPDATE User SET User.password = "${hash}" WHERE User.id = ${record.id}`));
+                });
+              });
+            });
+          });
+          // return the array of promises
+          return Promise.all(promises);
+        })
+        .catch(error => {
+          logger.error('error prepping promises array', error);
+        });
+  },
+  down: (queryInterface, Sequelize) => {
+    // logic for reverting the changes
+  },
+};