update eslint + config to latest

Also fix linting errors, most notably get rid of `var` keyword. Signed-off-by: Miroslav Bajtoš <mbajtoss@gmail.com>
2020-08-28 08:43:09 +02:00 · 2020-08-28 08:43:09 +02:00 · 7ce66b5b81
parent 40ce105e57
commit 7ce66b5b81
21 changed files with 422 additions and 445 deletions
--- a/example/app.js
+++ b/example/app.js
@ -4,11 +4,11 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var DataSource = require('loopback-datasource-juggler').DataSource;
+const DataSource = require('loopback-datasource-juggler').DataSource;
-var config = require('rc')('loopback', {dev: {mysql: {}}}).dev.mysql;
+const config = require('rc')('loopback', {dev: {mysql: {}}}).dev.mysql;
-var ds = new DataSource(require('../'), config);
+const ds = new DataSource(require('../'), config);
 function show(err, models) {
  if (err) {
@ -35,7 +35,7 @@ ds.discoverForeignKeys('inventory', show);
 ds.discoverExportedForeignKeys('location', show);
 ds.discoverAndBuildModels('weapon', {owner: 'strongloop', visited: {}, associations: true}, function(err, models) {
-  for (var m in models) {
+  for (const m in models) {
    models[m].all(show);
  }
 });
--- a/index.js
+++ b/index.js
@ -4,7 +4,7 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var SG = require('strong-globalize');
+const SG = require('strong-globalize');
 SG.SetRootDir(__dirname);
 module.exports = require('./lib/mysql.js');
--- a/lib/discovery.js
+++ b/lib/discovery.js
@ -4,7 +4,7 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var g = require('strong-globalize')();
+const g = require('strong-globalize')();
 module.exports = mixinDiscovery;
@ -13,20 +13,20 @@ module.exports = mixinDiscovery;
 * @param {Object} mysql mysql driver
 */
 function mixinDiscovery(MySQL, mysql) {
-  var async = require('async');
+  const async = require('async');
  function paginateSQL(sql, orderBy, options) {
    options = options || {};
-    var limitClause = '';
+    let limitClause = '';
    if (options.offset || options.skip || options.limit) {
      // Offset starts from 0
-      var offset = Number(options.offset || options.skip || 0);
+      let offset = Number(options.offset || options.skip || 0);
      if (isNaN(offset)) {
        offset = 0;
      }
      limitClause = ' LIMIT ' + offset;
      if (options.limit) {
-        var limit = Number(options.limit);
+        let limit = Number(options.limit);
        if (isNaN(limit)) {
          limit = 0;
        }
@ -45,7 +45,7 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {String} The SQL statement
   */
  MySQL.prototype.buildQuerySchemas = function(options) {
-    var sql = 'SELECT catalog_name as "catalog",' +
+    const sql = 'SELECT catalog_name as "catalog",' +
      ' schema_name as "schema"' +
      ' FROM information_schema.schemata';
    return paginateSQL(sql, 'schema_name', options);
@ -57,8 +57,8 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {string} The sql statement
   */
  MySQL.prototype.buildQueryTables = function(options) {
-    var sqlTables = null;
+    let sqlTables = null;
-    var schema = options.owner || options.schema;
+    const schema = options.owner || options.schema;
    if (options.all && !schema) {
      sqlTables = paginateSQL('SELECT \'table\' AS "type",' +
@ -87,9 +87,9 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {string} The sql statement
   */
  MySQL.prototype.buildQueryViews = function(options) {
-    var sqlViews = null;
+    let sqlViews = null;
    if (options.views) {
-      var schema = options.owner || options.schema;
+      const schema = options.owner || options.schema;
      if (options.all && !schema) {
        sqlViews = paginateSQL('SELECT \'view\' AS "type",' +
@ -155,7 +155,7 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {String} The sql statement
   */
  MySQL.prototype.buildQueryColumns = function(schema, table) {
-    var sql = null;
+    let sql = null;
    if (schema) {
      sql = paginateSQL('SELECT table_schema AS "owner",' +
        ' table_name AS "tableName",' +
@ -206,7 +206,7 @@ function mixinDiscovery(MySQL, mysql) {
  // http://docs.oracle.com/javase/6/docs/api/java/sql/DatabaseMetaData.html
  // #getPrimaryKeys(java.lang.String, java.lang.String, java.lang.String)
  MySQL.prototype.buildQueryPrimaryKeys = function(schema, table) {
-    var sql = 'SELECT table_schema AS "owner",' +
+    let sql = 'SELECT table_schema AS "owner",' +
      ' table_name AS "tableName",' +
      ' column_name AS "columnName",' +
      ' ordinal_position AS "keySeq",' +
@ -239,7 +239,7 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {string}
   */
  MySQL.prototype.buildQueryForeignKeys = function(schema, table) {
-    var sql =
+    let sql =
      'SELECT table_schema AS "fkOwner",' +
      ' constraint_name AS "fkName",' +
      ' table_name AS "fkTableName",' +
@ -276,7 +276,7 @@ function mixinDiscovery(MySQL, mysql) {
   * @returns {string}
   */
  MySQL.prototype.buildQueryExportedForeignKeys = function(schema, table) {
-    var sql = 'SELECT a.constraint_name AS "fkName",' +
+    let sql = 'SELECT a.constraint_name AS "fkName",' +
      ' a.table_schema AS "fkOwner",' +
      ' a.table_name AS "fkTableName",' +
      ' a.column_name AS "fkColumnName",' +
@ -306,11 +306,11 @@ function mixinDiscovery(MySQL, mysql) {
   */
  MySQL.prototype.buildPropertyType = function(columnDefinition, options) {
-    var mysqlType = columnDefinition.dataType;
+    const mysqlType = columnDefinition.dataType;
-    var columnType = columnDefinition.columnType;
+    const columnType = columnDefinition.columnType;
-    var dataLength = columnDefinition.dataLength;
+    const dataLength = columnDefinition.dataLength;
-    var type = mysqlType.toUpperCase();
+    const type = mysqlType.toUpperCase();
    switch (type) {
      case 'CHAR':
        if (!options.treatCHAR1AsString && columnType === 'char(1)') {
@ -379,13 +379,13 @@ function mixinDiscovery(MySQL, mysql) {
  // http://dev.mysql.com/doc/refman/5.7/en/numeric-type-overview.html
  // Currently default is the inverse of the recommendation for backward compatibility.
  MySQL.prototype.setDefaultOptions = function(options) {
-    var defaultOptions = {
+    const defaultOptions = {
      treatCHAR1AsString: false,
      treatBIT1AsBit: true,
      treatTINYINT1AsTinyInt: true,
    };
-    for (var opt in defaultOptions) {
+    for (const opt in defaultOptions) {
      if (defaultOptions.hasOwnProperty(opt) && !options.hasOwnProperty(opt)) {
        options[opt] = defaultOptions[opt];
      }
--- a/lib/enumFactory.js
+++ b/lib/enumFactory.js
@ -4,11 +4,11 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var g = require('strong-globalize')();
+const g = require('strong-globalize')();
-var EnumFactory = function() {
+const EnumFactory = function() {
  if (arguments.length > 0) {
-    var Enum = function Enum(arg) {
+    const Enum = function Enum(arg) {
      if (typeof arg === 'number' && arg % 1 == 0) {
        return Enum._values[arg];
      } else if (Enum[arg]) {
@ -21,11 +21,11 @@ var EnumFactory = function() {
        return '';
      }
    };
-    var dxList = [];
+    const dxList = [];
    // Want empty value to be at index 0 to match MySQL Enum values and
    // MySQL non-strict behavior.
    dxList.push('');
-    for (var arg in arguments) {
+    for (let arg in arguments) {
      arg = String(arguments[arg]);
      Object.defineProperty(Enum, arg.toUpperCase(), {
        configurable: false,
@ -55,8 +55,8 @@ var EnumFactory = function() {
 };
 function stringified(anEnum) {
-  var s = [];
+  const s = [];
-  for (var i in anEnum._values) {
+  for (const i in anEnum._values) {
    if (anEnum._values[i] != '') {
      s.push("'" + anEnum._values[i] + "'");
    }
--- a/lib/migration.js
+++ b/lib/migration.js
@ -4,8 +4,8 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var g = require('strong-globalize')();
+const g = require('strong-globalize')();
-var async = require('async');
+const async = require('async');
 module.exports = mixinMigration;
 /*!
@ -14,8 +14,8 @@ module.exports = mixinMigration;
 */
 function mixinMigration(MySQL, mysql) {
  MySQL.prototype.showFields = function(model, cb) {
-    var table = this.tableEscaped(model);
+    const table = this.tableEscaped(model);
-    var sql = 'SHOW FIELDS FROM ' + table;
+    const sql = 'SHOW FIELDS FROM ' + table;
    this.execute(sql, function(err, fields) {
      if (err) {
        return cb(err);
@ -26,8 +26,8 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.showIndexes = function(model, cb) {
-    var table = this.tableEscaped(model);
+    const table = this.tableEscaped(model);
-    var sql = 'SHOW INDEXES FROM ' + table;
+    const sql = 'SHOW INDEXES FROM ' + table;
    this.execute(sql, function(err, indexes) {
      if (err) {
        return cb(err);
@ -38,19 +38,20 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.getConstraintTrigger = function(model, actualFks, cb) {
-    var table = this.tableEscaped(model);
+    const table = this.tableEscaped(model);
-    var sql = 'SHOW CREATE TABLE ' + table;
+    const sql = 'SHOW CREATE TABLE ' + table;
    this.execute(sql, function(err, createTable) {
      if (err) {
        return cb(err);
      } else {
-        var matchConstraint = new RegExp('CONSTRAINT `([^`]+)` FOREIGN KEY \\(`([^`]+)`\\)' +
+        const matchConstraint = new RegExp('CONSTRAINT `([^`]+)` FOREIGN KEY \\(`([^`]+)`\\)' +
          ' REFERENCES `([^`]+)` \\(`([^`]+)`\\)' +
          '(?: ON DELETE (RESTRICT|CASCADE|SET NULL|NO ACTION|SET DEFAULT))?' +
          '(?: ON UPDATE (RESTRICT|CASCADE|SET NULL|NO ACTION|SET DEFAULT))?', 'g');
-        var rawConstraints = [];
+        const rawConstraints = [];
        let match;
        do {
-          var match = matchConstraint.exec(createTable[0]['Create Table']);
+          match = matchConstraint.exec(createTable[0]['Create Table']);
          if (match) {
            actualFks.forEach(function(fk) {
              if (fk.fkName === match[1]) {
@ -73,8 +74,8 @@ function mixinMigration(MySQL, mysql) {
    * @param {Function} [cb] The callback function
    */
  MySQL.prototype.autoupdate = function(models, cb) {
-    var self = this;
+    const self = this;
-    var foreignKeyStatements = [];
+    const foreignKeyStatements = [];
    if ((!cb) && ('function' === typeof models)) {
      cb = models;
@ -105,7 +106,7 @@ function mixinMigration(MySQL, mysql) {
                if (!err) {
                  // foreignKeys is a list of EXISTING fkeys here, so you don't need to recreate them again
                  // prepare fkSQL for new foreign keys
-                  var fkSQL = self.getForeignKeySQL(model,
+                  const fkSQL = self.getForeignKeySQL(model,
                    self.getModelDefinition(model).settings.foreignKeys,
                    foreignKeys);
                  self.addForeignKeys(model, fkSQL, function(err, result) {
@ -141,9 +142,9 @@ function mixinMigration(MySQL, mysql) {
   * @param cb
   */
  MySQL.prototype.createTable = function(model, cb) {
-    var metadata = this.getModelDefinition(model).settings[this.name];
+    const metadata = this.getModelDefinition(model).settings[this.name];
-    var engine = metadata && metadata.engine;
+    const engine = metadata && metadata.engine;
-    var sql = 'CREATE TABLE ' + this.tableEscaped(model) +
+    let sql = 'CREATE TABLE ' + this.tableEscaped(model) +
      ' (\n  ' + this.buildColumnDefinitions(model) + '\n)';
    if (engine) {
      sql += 'ENGINE=' + engine + '\n';
@ -158,8 +159,8 @@ function mixinMigration(MySQL, mysql) {
   * @param {Function} [cb] The callback function
   */
  MySQL.prototype.isActual = function(models, cb) {
-    var self = this;
+    const self = this;
-    var ok = false;
+    let ok = false;
    if ((!cb) && ('function' === typeof models)) {
      cb = models;
@ -195,17 +196,17 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.getColumnsToAdd = function(model, actualFields) {
-    var self = this;
+    const self = this;
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
-    var propNames = Object.keys(m.properties).filter(function(name) {
+    const propNames = Object.keys(m.properties).filter(function(name) {
      return !!m.properties[name];
    });
-    var sql = [];
+    const sql = [];
    propNames.forEach(function(propName) {
      if (m.properties[propName] && self.id(model, propName)) return;
-      var found;
+      let found;
-      var colName = expectedColNameForModel(propName, m);
+      const colName = expectedColNameForModel(propName, m);
      if (actualFields) {
        actualFields.forEach(function(f) {
          if (f.Field === colName) {
@ -222,9 +223,9 @@ function mixinMigration(MySQL, mysql) {
    });
    function actualize(propName, oldSettings) {
-      var newSettings = m.properties[propName];
+      const newSettings = m.properties[propName];
      if (newSettings && changed(newSettings, oldSettings)) {
-        var pName = self.columnEscaped(model, propName);
+        const pName = self.columnEscaped(model, propName);
        sql.push('CHANGE COLUMN ' + pName + ' ' + pName + ' ' +
          self.buildColumnDefinition(model, propName));
      }
@ -254,22 +255,22 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.getColumnsToDrop = function(model, actualFields) {
-    var self = this;
+    const self = this;
-    var fields = actualFields;
+    const fields = actualFields;
-    var sql = [];
+    const sql = [];
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
-    var propNames = Object.keys(m.properties).filter(function(name) {
+    const propNames = Object.keys(m.properties).filter(function(name) {
      return !!m.properties[name];
    });
    // drop columns
    if (fields) {
      fields.forEach(function(f) {
-        var colNames = propNames.map(function expectedColName(propName) {
+        const colNames = propNames.map(function expectedColName(propName) {
          return expectedColNameForModel(propName, m);
        });
-        var index = colNames.indexOf(f.Field);
+        const index = colNames.indexOf(f.Field);
-        var propName = index >= 0 ? propNames[index] : f.Field;
+        const propName = index >= 0 ? propNames[index] : f.Field;
-        var notFound = !~index;
+        const notFound = !~index;
        if (m.properties[propName] && self.id(model, propName)) return;
        if (notFound || !m.properties[propName]) {
          sql.push('DROP COLUMN ' + self.client.escapeId(f.Field));
@ -280,20 +281,20 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.addIndexes = function(model, actualIndexes) {
-    var self = this;
+    const self = this;
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
-    var propNames = Object.keys(m.properties).filter(function(name) {
+    const propNames = Object.keys(m.properties).filter(function(name) {
      return !!m.properties[name];
    });
-    var indexNames = m.settings.indexes && Object.keys(m.settings.indexes).filter(function(name) {
+    const indexNames = m.settings.indexes && Object.keys(m.settings.indexes).filter(function(name) {
      return !!m.settings.indexes[name];
    }) || [];
-    var sql = [];
+    const sql = [];
-    var ai = {};
+    const ai = {};
    if (actualIndexes) {
      actualIndexes.forEach(function(i) {
-        var name = i.Key_name;
+        const name = i.Key_name;
        if (!ai[name]) {
          ai[name] = {
            info: i,
@ -303,7 +304,7 @@ function mixinMigration(MySQL, mysql) {
        ai[name].columns[i.Seq_in_index - 1] = i.Column_name;
      });
    }
-    var aiNames = Object.keys(ai);
+    const aiNames = Object.keys(ai);
    // remove indexes
    aiNames.forEach(function(indexName) {
@ -322,19 +323,20 @@ function mixinMigration(MySQL, mysql) {
          return;
        }
        // second: check multiple indexes
-        var orderMatched = true;
+        let orderMatched = true;
        if (indexNames.indexOf(indexName) !== -1) {
          // check if indexes are configured as "columns"
          if (m.settings.indexes[indexName].columns) {
            m.settings.indexes[indexName].columns.split(/,\s*/).forEach(
              function(columnName, i) {
                if (ai[indexName].columns[i] !== columnName) orderMatched = false;
-              });
+              },
            );
          } else if (m.settings.indexes[indexName].keys) {
            // if indexes are configured as "keys"
-            var index = 0;
+            let index = 0;
-            for (var key in m.settings.indexes[indexName].keys) {
+            for (const key in m.settings.indexes[indexName].keys) {
-              var sortOrder = m.settings.indexes[indexName].keys[key];
+              const sortOrder = m.settings.indexes[indexName].keys[key];
              if (ai[indexName].columns[index] !== key) {
                orderMatched = false;
                break;
@ -356,17 +358,17 @@ function mixinMigration(MySQL, mysql) {
    // add single-column indexes
    propNames.forEach(function(propName) {
-      var i = m.properties[propName].index;
+      const i = m.properties[propName].index;
      if (!i) {
        return;
      }
-      var found = ai[propName] && ai[propName].info;
+      const found = ai[propName] && ai[propName].info;
      if (!found) {
-        var colName = expectedColNameForModel(propName, m);
+        const colName = expectedColNameForModel(propName, m);
-        var pName = self.client.escapeId(colName);
+        const pName = self.client.escapeId(colName);
-        var indexName = self.client.escapeId(propName);
+        const indexName = self.client.escapeId(propName);
-        var type = '';
+        let type = '';
-        var kind = '';
+        let kind = '';
        if (i.type) {
          type = 'USING ' + i.type;
        }
@ -385,12 +387,12 @@ function mixinMigration(MySQL, mysql) {
    // add multi-column indexes
    indexNames.forEach(function(indexName) {
-      var i = m.settings.indexes[indexName];
+      const i = m.settings.indexes[indexName];
-      var found = ai[indexName] && ai[indexName].info;
+      const found = ai[indexName] && ai[indexName].info;
      if (!found) {
-        var iName = self.client.escapeId(indexName);
+        const iName = self.client.escapeId(indexName);
-        var type = '';
+        let type = '';
-        var kind = '';
+        let kind = '';
        if (i.type) {
          type = 'USING ' + i.type;
        }
@ -401,11 +403,11 @@ function mixinMigration(MySQL, mysql) {
          kind = 'UNIQUE';
        }
-        var indexedColumns = [];
+        const indexedColumns = [];
-        var columns = '';
+        let columns = '';
        // if indexes are configured as "keys"
        if (i.keys) {
-          for (var key in i.keys) {
+          for (const key in i.keys) {
            if (i.keys[key] !== -1) {
              indexedColumns.push(key);
            } else {
@ -432,20 +434,20 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.getForeignKeySQL = function(model, actualFks, existingFks) {
-    var self = this;
+    const self = this;
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
-    var addFksSql = [];
+    const addFksSql = [];
    existingFks = existingFks || [];
    if (actualFks) {
-      var keys = Object.keys(actualFks);
+      const keys = Object.keys(actualFks);
-      for (var i = 0; i < keys.length; i++) {
+      for (let i = 0; i < keys.length; i++) {
        // all existing fks are already checked in MySQL.prototype.dropForeignKeys
        // so we need check only names - skip if found
        if (existingFks.filter(function(fk) {
          return fk.fkName === keys[i];
        }).length > 0) continue;
-        var constraint = self.buildForeignKeyDefinition(model, keys[i]);
+        const constraint = self.buildForeignKeyDefinition(model, keys[i]);
        if (constraint) {
          addFksSql.push('ADD ' + constraint);
@ -456,8 +458,8 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.addForeignKeys = function(model, fkSQL, cb) {
-    var self = this;
+    const self = this;
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
    if ((!cb) && ('function' === typeof fkSQL)) {
      cb = fkSQL;
@ -465,7 +467,7 @@ function mixinMigration(MySQL, mysql) {
    }
    if (!fkSQL) {
-      var newFks = m.settings.foreignKeys;
+      const newFks = m.settings.foreignKeys;
      if (newFks)
        fkSQL = self.getForeignKeySQL(model, newFks);
    }
@ -479,25 +481,25 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.dropForeignKeys = function(model, actualFks) {
-    var self = this;
+    const self = this;
-    var m = this.getModelDefinition(model);
+    const m = this.getModelDefinition(model);
-    var fks = actualFks;
+    const fks = actualFks;
-    var sql = [];
+    const sql = [];
-    var correctFks = m.settings.foreignKeys || {};
+    const correctFks = m.settings.foreignKeys || {};
    // drop foreign keys for removed fields
    if (fks && fks.length) {
-      var removedFks = [];
+      const removedFks = [];
      fks.forEach(function(fk) {
-        var needsToDrop = false;
+        let needsToDrop = false;
-        var newFk = correctFks[fk.fkName];
+        const newFk = correctFks[fk.fkName];
        if (newFk) {
-          var fkCol = expectedColNameForModel(newFk.foreignKey, m);
+          const fkCol = expectedColNameForModel(newFk.foreignKey, m);
-          var fkEntity = self.getModelDefinition(newFk.entity);
+          const fkEntity = self.getModelDefinition(newFk.entity);
-          var fkRefKey = expectedColNameForModel(newFk.entityKey, fkEntity);
+          const fkRefKey = expectedColNameForModel(newFk.entityKey, fkEntity);
-          var fkEntityName = (typeof newFk.entity === 'object') ? newFk.entity.name : newFk.entity;
+          const fkEntityName = (typeof newFk.entity === 'object') ? newFk.entity.name : newFk.entity;
-          var fkRefTable = self.table(fkEntityName);
+          const fkRefTable = self.table(fkEntityName);
          needsToDrop = fkCol != fk.fkColumnName ||
                        fkRefKey != fk.pkColumnName ||
                        fkRefTable != fk.pkTableName ||
@ -515,7 +517,7 @@ function mixinMigration(MySQL, mysql) {
      // update out list of existing keys by removing dropped keys
      removedFks.forEach(function(k) {
-        var index = actualFks.indexOf(k);
+        const index = actualFks.indexOf(k);
        if (index !== -1) actualFks.splice(index, 1);
      });
    }
@ -534,9 +536,9 @@ function mixinMigration(MySQL, mysql) {
      checkOnly = done || false;
      done = actualFks;
    }
-    var self = this;
+    const self = this;
-    var statements = [];
+    let statements = [];
    async.series([
      function(cb) {
@ -561,12 +563,12 @@ function mixinMigration(MySQL, mysql) {
      // determine if there are column, index, or foreign keys changes (all require update)
      if (statements.length) {
        // get the required alter statements
-        var alterStmt = self.getAlterStatement(model, statements);
+        const alterStmt = self.getAlterStatement(model, statements);
-        var stmtList = [alterStmt];
+        const stmtList = [alterStmt];
        // set up an object to pass back all changes, changes that have been run,
        // and foreign key statements that haven't been run
-        var retValues = {
+        const retValues = {
          statements: stmtList,
          query: stmtList.join(';'),
        };
@ -588,16 +590,16 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.buildForeignKeyDefinition = function(model, keyName) {
-    var definition = this.getModelDefinition(model);
+    const definition = this.getModelDefinition(model);
-    var fk = definition.settings.foreignKeys[keyName];
+    const fk = definition.settings.foreignKeys[keyName];
    if (fk) {
      // get the definition of the referenced object
-      var fkEntityName = (typeof fk.entity === 'object') ? fk.entity.name : fk.entity;
+      const fkEntityName = (typeof fk.entity === 'object') ? fk.entity.name : fk.entity;
      // verify that the other model in the same DB
      if (this._models[fkEntityName]) {
-        var constraint = ' CONSTRAINT ' + this.client.escapeId(fk.name) +
+        let constraint = ' CONSTRAINT ' + this.client.escapeId(fk.name) +
          ' FOREIGN KEY (`' + expectedColNameForModel(fk.foreignKey, definition) + '`)' +
          ' REFERENCES ' + this.tableEscaped(fkEntityName) +
          '(' + this.client.escapeId(fk.entityKey) + ')';
@ -615,17 +617,17 @@ function mixinMigration(MySQL, mysql) {
  MySQL.prototype.buildColumnDefinitions =
    MySQL.prototype.propertiesSQL = function(model) {
-      var self = this;
+      const self = this;
-      var pks = this.idNames(model).map(function(i) {
+      const pks = this.idNames(model).map(function(i) {
        return self.columnEscaped(model, i);
      });
-      var definition = this.getModelDefinition(model);
+      const definition = this.getModelDefinition(model);
-      var sql = [];
+      const sql = [];
      if (pks.length === 1) {
-        var idName = this.idName(model);
+        const idName = this.idName(model);
-        var idProp = this.getModelDefinition(model).properties[idName];
+        const idProp = this.getModelDefinition(model).properties[idName];
        if (idProp.generated) {
          sql.push(self.columnEscaped(model, idName) + ' ' +
            self.buildColumnDefinition(model, idName) + ' AUTO_INCREMENT PRIMARY KEY');
@ -639,14 +641,14 @@ function mixinMigration(MySQL, mysql) {
        if (self.id(model, prop) && pks.length === 1) {
          return;
        }
-        var colName = self.columnEscaped(model, prop);
+        const colName = self.columnEscaped(model, prop);
        sql.push(colName + ' ' + self.buildColumnDefinition(model, prop));
      });
      if (pks.length > 1) {
        sql.push('PRIMARY KEY(' + pks.join(',') + ')');
      }
-      var indexes = self.buildIndexes(model);
+      const indexes = self.buildIndexes(model);
      indexes.forEach(function(i) {
        sql.push(i);
      });
@ -655,20 +657,20 @@ function mixinMigration(MySQL, mysql) {
    };
  MySQL.prototype.buildIndex = function(model, property) {
-    var prop = this.getModelDefinition(model).properties[property];
+    const prop = this.getModelDefinition(model).properties[property];
-    var i = prop && prop.index;
+    const i = prop && prop.index;
    if (!i) {
      return '';
    }
-    var type = '';
+    let type = '';
-    var kind = '';
+    let kind = '';
    if (i.type) {
      type = 'USING ' + i.type;
    }
    if (i.kind) {
      kind = i.kind;
    }
-    var columnName = this.columnEscaped(model, property);
+    const columnName = this.columnEscaped(model, property);
    if (kind && type) {
      return (kind + ' INDEX ' + columnName + ' (' + columnName + ') ' + type);
    } else {
@ -680,15 +682,15 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.buildIndexes = function(model) {
-    var self = this;
+    const self = this;
-    var indexClauses = [];
+    const indexClauses = [];
-    var definition = this.getModelDefinition(model);
+    const definition = this.getModelDefinition(model);
-    var indexes = definition.settings.indexes || {};
+    const indexes = definition.settings.indexes || {};
    // Build model level indexes
-    for (var index in  indexes) {
+    for (const index in indexes) {
-      var i = indexes[index];
+      const i = indexes[index];
-      var type = '';
+      let type = '';
-      var kind = '';
+      let kind = '';
      if (i.type) {
        type = 'USING ' + i.type;
      }
@ -699,13 +701,13 @@ function mixinMigration(MySQL, mysql) {
        // if index unique indicator is configured
        kind = 'UNIQUE';
      }
-      var indexedColumns = [];
+      const indexedColumns = [];
-      var indexName = this.escapeName(index);
+      const indexName = this.escapeName(index);
-      var columns = '';
+      let columns = '';
      // if indexes are configured as "keys"
      if (i.keys) {
        // for each field in "keys" object
-        for (var key in i.keys) {
+        for (const key in i.keys) {
          if (i.keys[key] !== -1) {
            indexedColumns.push(this.escapeName(key));
          } else {
@ -731,8 +733,8 @@ function mixinMigration(MySQL, mysql) {
      }
    }
    // Define index for each of the properties
-    for (var p in definition.properties) {
+    for (const p in definition.properties) {
-      var propIndex = self.buildIndex(model, p);
+      const propIndex = self.buildIndex(model, p);
      if (propIndex) {
        indexClauses.push(propIndex);
      }
@ -741,8 +743,8 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.buildColumnDefinition = function(model, prop) {
-    var p = this.getModelDefinition(model).properties[prop];
+    const p = this.getModelDefinition(model).properties[prop];
-    var line = this.columnDataType(model, prop) + ' ' +
+    const line = this.columnDataType(model, prop) + ' ' +
      (this.isNullable(p) ? 'NULL' : 'NOT NULL');
    return columnDefault(p, line);
  };
@ -750,18 +752,18 @@ function mixinMigration(MySQL, mysql) {
  // override this function from base connector to allow mysql connector to
  // accept dataPrecision and dataScale as column specific properties
  MySQL.prototype.columnDataType = function(model, property) {
-    var columnMetadata = this.columnMetadata(model, property);
+    const columnMetadata = this.columnMetadata(model, property);
-    var colType = columnMetadata && columnMetadata.dataType;
+    let colType = columnMetadata && columnMetadata.dataType;
    if (colType) {
      colType = colType.toUpperCase();
    }
-    var prop = this.getModelDefinition(model).properties[property];
+    const prop = this.getModelDefinition(model).properties[property];
    if (!prop) {
      return null;
    }
-    var colLength = columnMetadata && columnMetadata.dataLength || prop.length || prop.limit;
+    const colLength = columnMetadata && columnMetadata.dataLength || prop.length || prop.limit;
-    var colPrecision = columnMetadata && columnMetadata.dataPrecision;
+    const colPrecision = columnMetadata && columnMetadata.dataPrecision;
-    var colScale = columnMetadata && columnMetadata.dataScale;
+    const colScale = columnMetadata && columnMetadata.dataScale;
    // info on setting column specific properties
    // i.e dataLength, dataPrecision, dataScale
    // https://loopback.io/doc/en/lb3/Model-definition-JSON-file.html
@ -775,8 +777,8 @@ function mixinMigration(MySQL, mysql) {
  };
  MySQL.prototype.buildColumnType = function buildColumnType(propertyDefinition) {
-    var dt = '';
+    let dt = '';
-    var p = propertyDefinition;
+    const p = propertyDefinition;
    switch (p.type.name) {
      default:
      case 'JSON':
@ -822,7 +824,7 @@ function mixinMigration(MySQL, mysql) {
      return line;
    }
    if (typeof p.mysql !== 'undefined' && p.mysql.default) {
-      var columnDefault = p.mysql.default;
+      const columnDefault = p.mysql.default;
      if (typeof columnDefault === 'number') {
        return line + ' DEFAULT ' + columnDefault;
      }
@ -836,7 +838,7 @@ function mixinMigration(MySQL, mysql) {
  }
  function columnType(p, defaultType) {
-    var dt = defaultType;
+    let dt = defaultType;
    if (p.mysql && p.mysql.dataType) {
      dt = String(p.mysql.dataType);
    } else if (p.dataType) {
@ -846,12 +848,13 @@ function mixinMigration(MySQL, mysql) {
  }
  function stringOptionsByType(p, columnType) {
    let len;
    switch (columnType.toLowerCase()) {
      default:
      case 'varchar':
        // The maximum length for an ID column is 1000 bytes
        // The maximum row size is 64K
-        var len = p.length || p.limit ||
+        len = p.length || p.limit ||
          ((p.type !== String) ? 4096 : p.id || p.index ? 255 : 512);
        columnType += '(' + len + ')';
        break;
@ -908,8 +911,8 @@ function mixinMigration(MySQL, mysql) {
  }
  function floatingPointOptions(p, columnType) {
-    var precision = 16;
+    let precision = 16;
-    var scale = 8;
+    let scale = 8;
    if (p.precision) {
      precision = Number(p.precision);
    }
@ -929,8 +932,8 @@ function mixinMigration(MySQL, mysql) {
  /*  JS. Also, defaulting column to (9,2) and not allowing non-specified 'DECIMAL'   */
  /*  declaration which would default to DECIMAL(10,0). Instead defaulting to (9,2).  */
  function fixedPointOptions(p, columnType) {
-    var precision = 9;
+    let precision = 9;
-    var scale = 2;
+    let scale = 2;
    if (p.precision) {
      precision = Number(p.precision);
    }
@ -942,7 +945,7 @@ function mixinMigration(MySQL, mysql) {
  }
  function integerOptions(p, columnType) {
-    var tmp = 0;
+    let tmp = 0;
    if (p.display || p.limit) {
      tmp = Number(p.display || p.limit);
    }
@ -1005,7 +1008,7 @@ function mixinMigration(MySQL, mysql) {
  }
  function dateOptions(p, columnType) {
-    var precision = 0;
+    let precision = 0;
    if (p.precision) {
      precision = Number(p.precision);
@ -1022,11 +1025,11 @@ function mixinMigration(MySQL, mysql) {
    return columnType;
  }
  function expectedColNameForModel(propName, modelToCheck) {
-    var mysql = modelToCheck.properties[propName].mysql;
+    const mysql = modelToCheck.properties[propName].mysql;
    if (typeof mysql === 'undefined') {
      return propName;
    }
-    var colName = mysql.columnName;
+    const colName = mysql.columnName;
    if (typeof colName === 'undefined') {
      return propName;
    }
--- a/lib/mysql.js
+++ b/lib/mysql.js
@ -4,19 +4,19 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var g = require('strong-globalize')();
+const g = require('strong-globalize')();
 /*!
 * Module dependencies
 */
-var mysql = require('mysql');
+const mysql = require('mysql');
-var SqlConnector = require('loopback-connector').SqlConnector;
+const SqlConnector = require('loopback-connector').SqlConnector;
-var ParameterizedSQL = SqlConnector.ParameterizedSQL;
+const ParameterizedSQL = SqlConnector.ParameterizedSQL;
-var EnumFactory = require('./enumFactory').EnumFactory;
+const EnumFactory = require('./enumFactory').EnumFactory;
-var debug = require('debug')('loopback:connector:mysql');
+const debug = require('debug')('loopback:connector:mysql');
-var setHttpCode = require('./set-http-code');
+const setHttpCode = require('./set-http-code');
 /**
 * @module loopback-connector-mysql
@ -49,8 +49,8 @@ exports.initialize = function initializeDataSource(dataSource, callback) {
 exports.MySQL = MySQL;
 function defineMySQLTypes(dataSource) {
-  var modelBuilder = dataSource.modelBuilder;
+  const modelBuilder = dataSource.modelBuilder;
-  var defineType = modelBuilder.defineValueType ?
+  const defineType = modelBuilder.defineValueType ?
    // loopback-datasource-juggler 2.x
    modelBuilder.defineValueType.bind(modelBuilder) :
    // loopback-datasource-juggler 1.x
@ -75,9 +75,9 @@ function MySQL(settings) {
 require('util').inherits(MySQL, SqlConnector);
 MySQL.prototype.connect = function(callback) {
-  var self = this;
+  const self = this;
-  var options = generateOptions(this.settings);
+  const options = generateOptions(this.settings);
-  var s = self.settings || {};
+  const s = self.settings || {};
  if (this.client) {
    if (callback) {
@ -88,7 +88,7 @@ MySQL.prototype.connect = function(callback) {
  } else {
    this.client = mysql.createPool(options);
    this.client.getConnection(function(err, connection) {
-      var conn = connection;
+      const conn = connection;
      if (!err) {
        if (self.debug) {
          debug('MySQL connection is established: ' + self.settings || {});
@ -105,7 +105,7 @@ MySQL.prototype.connect = function(callback) {
 };
 function generateOptions(settings) {
-  var s = settings || {};
+  const s = settings || {};
  if (s.collation) {
    // Charset should be first 'chunk' of collation.
    s.charset = s.collation.substr(0, s.collation.indexOf('_'));
@ -121,7 +121,7 @@ function generateOptions(settings) {
    s.connectionLimit = 10;
  }
-  var options;
+  let options;
  if (s.url) {
    // use url to override other settings if url provided
    options = s.url;
@ -145,7 +145,7 @@ function generateOptions(settings) {
    // Take other options for mysql driver
    // See https://github.com/strongloop/loopback-connector-mysql/issues/46
-    for (var p in s) {
+    for (const p in s) {
      if (p === 'database' && s.createDatabase) {
        continue;
      }
@ -170,10 +170,10 @@ function generateOptions(settings) {
 * @param {Function} [callback] The callback after the SQL statement is executed
 */
 MySQL.prototype.executeSQL = function(sql, params, options, callback) {
-  var self = this;
+  const self = this;
-  var client = this.client;
+  const client = this.client;
-  var debugEnabled = debug.enabled;
+  const debugEnabled = debug.enabled;
-  var db = this.settings.database;
+  const db = this.settings.database;
  if (typeof callback !== 'function') {
    throw new Error(g.f('{{callback}} should be a function'));
  }
@ -181,7 +181,7 @@ MySQL.prototype.executeSQL = function(sql, params, options, callback) {
    debug('SQL: %s, params: %j', sql, params);
  }
-  var transaction = options.transaction;
+  const transaction = options.transaction;
  function handleResponse(connection, err, result) {
    if (!transaction) {
@ -214,9 +214,9 @@ MySQL.prototype.executeSQL = function(sql, params, options, callback) {
      connection.query('USE ??', [db], function(err) {
        if (err) {
          if (err && err.message.match(/(^|: )unknown database/i)) {
-            var charset = self.settings.charset;
+            const charset = self.settings.charset;
-            var collation = self.settings.collation;
+            const collation = self.settings.collation;
-            var q = 'CREATE DATABASE ?? CHARACTER SET ?? COLLATE ??';
+            const q = 'CREATE DATABASE ?? CHARACTER SET ?? COLLATE ??';
            connection.query(q, [db, charset, collation], function(err) {
              if (!err) {
                connection.query('USE ??', [db], function(err) {
@ -252,12 +252,12 @@ MySQL.prototype.executeSQL = function(sql, params, options, callback) {
 };
 MySQL.prototype._modifyOrCreate = function(model, data, options, fields, cb) {
-  var sql = new ParameterizedSQL('INSERT INTO ' + this.tableEscaped(model));
+  const sql = new ParameterizedSQL('INSERT INTO ' + this.tableEscaped(model));
-  var columnValues = fields.columnValues;
+  const columnValues = fields.columnValues;
-  var fieldNames = fields.names;
+  const fieldNames = fields.names;
  if (fieldNames.length) {
    sql.merge('(' + fieldNames.join(',') + ')', '');
-    var values = ParameterizedSQL.join(columnValues, ',');
+    const values = ParameterizedSQL.join(columnValues, ',');
    values.sql = 'VALUES(' + values.sql + ')';
    sql.merge(values);
  } else {
@ -265,8 +265,8 @@ MySQL.prototype._modifyOrCreate = function(model, data, options, fields, cb) {
  }
  sql.merge('ON DUPLICATE KEY UPDATE');
-  var setValues = [];
+  const setValues = [];
-  for (var i = 0, n = fields.names.length; i < n; i++) {
+  for (let i = 0, n = fields.names.length; i < n; i++) {
    if (!fields.properties[i].id) {
      setValues.push(new ParameterizedSQL(fields.names[i] + '=' +
          columnValues[i].sql, columnValues[i].params));
@ -279,7 +279,7 @@ MySQL.prototype._modifyOrCreate = function(model, data, options, fields, cb) {
    if (!err && info && info.insertId) {
      data.id = info.insertId;
    }
-    var meta = {};
+    const meta = {};
    // When using the INSERT ... ON DUPLICATE KEY UPDATE statement,
    // the returned value is as follows:
    // 1 for each successful INSERT.
@ -300,7 +300,7 @@ MySQL.prototype._modifyOrCreate = function(model, data, options, fields, cb) {
 * @param {Function} [cb] The callback function
 */
 MySQL.prototype.replaceOrCreate = function(model, data, options, cb) {
-  var fields = this.buildReplaceFields(model, data);
+  const fields = this.buildReplaceFields(model, data);
  this._modifyOrCreate(model, data, options, fields, cb);
 };
@ -314,12 +314,12 @@ MySQL.prototype.replaceOrCreate = function(model, data, options, cb) {
 */
 MySQL.prototype.save =
 MySQL.prototype.updateOrCreate = function(model, data, options, cb) {
-  var fields =  this.buildFields(model, data);
+  const fields = this.buildFields(model, data);
  this._modifyOrCreate(model, data, options, fields, cb);
 };
 MySQL.prototype.getInsertedId = function(model, info) {
-  var insertedId = info && typeof info.insertId === 'number' ?
+  const insertedId = info && typeof info.insertId === 'number' ?
    info.insertId : undefined;
  return insertedId;
 };
@ -339,7 +339,7 @@ MySQL.prototype.toColumnValue = function(prop, val) {
      return val;
    } else {
      try {
-        var castNull = prop.type(val);
+        const castNull = prop.type(val);
        if (prop.type === Object) {
          return JSON.stringify(castNull);
        }
@ -395,7 +395,7 @@ MySQL.prototype.toColumnValue = function(prop, val) {
 };
 MySQL.prototype._serializeObject = function(obj) {
-  var val;
+  let val;
  if (obj && typeof obj.toJSON === 'function') {
    obj = obj.toJSON();
  }
@ -495,7 +495,7 @@ MySQL.prototype._buildLimit = function(model, limit, offset) {
 };
 MySQL.prototype.applyPagination = function(model, stmt, filter) {
-  var limitClause = this._buildLimit(model, filter.limit,
+  const limitClause = this._buildLimit(model, filter.limit,
    filter.offset || filter.skip);
  return stmt.merge(limitClause);
 };
@ -519,7 +519,7 @@ MySQL.prototype.getPlaceholderForValue = function(key) {
 };
 MySQL.prototype.getCountForAffectedRows = function(model, info) {
-  var affectedRows = info && typeof info.affectedRows === 'number' ?
+  const affectedRows = info && typeof info.affectedRows === 'number' ?
    info.affectedRows : undefined;
  return affectedRows;
 };
@ -548,7 +548,7 @@ MySQL.prototype.ping = function(cb) {
 MySQL.prototype.buildExpression = function(columnName, operator, operatorValue,
  propertyDefinition) {
  if (operator === 'regexp') {
-    var clause = columnName + ' REGEXP ?';
+    let clause = columnName + ' REGEXP ?';
    // By default, MySQL regexp is not case sensitive. (https://dev.mysql.com/doc/refman/5.7/en/regexp.html)
    // To allow case sensitive regexp query, it has to be binded to a `BINARY` type.
    // If ignore case is not specified, search it as case sensitive.
--- a/lib/set-http-code.js
+++ b/lib/set-http-code.js
@ -5,9 +5,9 @@
 'use strict';
-var _ = require('lodash');
+const _ = require('lodash');
-var codes = {
+const codes = {
  '404': [
    'ER_DB_DROP_EXISTS',
    'ER_BAD_TABLE_ERROR',
@ -32,10 +32,10 @@ module.exports = function(err) {
    err = new Error(err); // Sucks that we weren't given an error object...
  }
  // Find error prefix
-  var msg = err.message;
+  const msg = err.message;
-  var sqlError = msg.substring(0, msg.indexOf(':'));
+  const sqlError = msg.substring(0, msg.indexOf(':'));
-  for (var code in codes) {
+  for (const code in codes) {
    if (_.includes(codes[code], sqlError)) {
      err.statusCode = code;
    }
--- a/lib/transaction.js
+++ b/lib/transaction.js
@ -4,7 +4,7 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var debug = require('debug')('loopback:connector:mysql:transaction');
+const debug = require('debug')('loopback:connector:mysql:transaction');
 module.exports = mixinTransaction;
 /*!
@ -30,7 +30,8 @@ function mixinTransaction(MySQL, mysql) {
              if (err) return cb(err);
              return cb(null, connection);
            });
-          });
+          },
        );
      } else {
        connection.beginTransaction(function(err) {
          if (err) return cb(err);
--- a/package.json
+++ b/package.json
@ -29,8 +29,8 @@
  },
  "devDependencies": {
    "bluebird": "~2.9.10",
-    "eslint": "^4.3.0",
+    "eslint": "^7.7.0",
-    "eslint-config-loopback": "^8.0.0",
+    "eslint-config-loopback": "^13.1.0",
    "juggler-v3": "file:./deps/juggler-v3",
    "juggler-v4": "file:./deps/juggler-v4",
    "loopback-datasource-juggler": "^3.0.0 || ^4.0.0",
--- a/pretest.js
+++ b/pretest.js
@ -18,12 +18,12 @@ process.env.MYSQL_USER =
 process.env.MYSQL_PASSWORD =
  process.env.MYSQL_PASSWORD || process.env.MYSQL_PASSWORD || 'test';
-var fs = require('fs');
+const fs = require('fs');
-var cp = require('child_process');
+const cp = require('child_process');
-var sql = fs.createReadStream(require.resolve('./test/schema.sql'));
+const sql = fs.createReadStream(require.resolve('./test/schema.sql'));
-var stdio = ['pipe', process.stdout, process.stderr];
+const stdio = ['pipe', process.stdout, process.stderr];
-var args = ['--user=' + process.env.MYSQL_USER];
+const args = ['--user=' + process.env.MYSQL_USER];
 if (process.env.MYSQL_HOST) {
  args.push('--host=' + process.env.MYSQL_HOST);
@ -36,7 +36,7 @@ if (process.env.MYSQL_PASSWORD) {
 }
 console.log('seeding DB with example db...');
-var mysql = cp.spawn('mysql', args, {stdio: stdio});
+const mysql = cp.spawn('mysql', args, {stdio: stdio});
 sql.pipe(mysql.stdin);
 mysql.on('exit', function(code) {
  console.log('done seeding DB');
--- a/test/connection.test.js
+++ b/test/connection.test.js
@ -5,13 +5,13 @@
 'use strict';
 require('./init.js');
-var assert = require('assert');
+const assert = require('assert');
-var should = require('should');
+const should = require('should');
-var DataSource = require('loopback-datasource-juggler').DataSource;
+const DataSource = require('loopback-datasource-juggler').DataSource;
-var mysqlConnector = require('../');
+const mysqlConnector = require('../');
-var url = require('url');
+const url = require('url');
-var db, DummyModel, odb, config;
+let db, DummyModel, odb, config;
 describe('connections', function() {
  before(function() {
@ -25,13 +25,13 @@ describe('connections', function() {
  });
  it('should pass with valid settings', function(done) {
-    var db = new DataSource(mysqlConnector, config);
+    const db = new DataSource(mysqlConnector, config);
    db.ping(done);
  });
  it('ignores all other settings when url is present', function(done) {
-    var formatedUrl = generateURL(config);
+    const formatedUrl = generateURL(config);
-    var dbConfig = {
+    const dbConfig = {
      url: formatedUrl,
      host: 'invalid-hostname',
      port: 80,
@ -40,15 +40,15 @@ describe('connections', function() {
      password: 'invalid-password',
    };
-    var db = new DataSource(mysqlConnector, dbConfig);
+    const db = new DataSource(mysqlConnector, dbConfig);
    db.ping(done);
  });
  it('should use utf8 charset', function(done) {
-    var test_set = /utf8/;
+    const test_set = /utf8/;
-    var test_collo = /utf8_general_ci/;
+    const test_collo = /utf8_general_ci/;
-    var test_set_str = 'utf8';
+    const test_set_str = 'utf8';
-    var test_set_collo = 'utf8_general_ci';
+    const test_set_collo = 'utf8_general_ci';
    charsetTest(test_set, test_collo, test_set_str, test_set_collo, done);
  });
@ -60,8 +60,8 @@ describe('connections', function() {
  });
  it('should disconnect then connect and ORM should work', function() {
-    var ds = new DataSource(mysqlConnector, config);
+    const ds = new DataSource(mysqlConnector, config);
-    var Student = ds.define('Student', {
+    const Student = ds.define('Student', {
      name: {type: String, length: 255},
      age: {type: Number},
    }, {
@ -95,10 +95,10 @@ describe('connections', function() {
  });
  it('should use latin1 charset', function(done) {
-    var test_set = /latin1/;
+    const test_set = /latin1/;
-    var test_collo = /latin1_general_ci/;
+    const test_collo = /latin1_general_ci/;
-    var test_set_str = 'latin1';
+    const test_set_str = 'latin1';
-    var test_set_collo = 'latin1_general_ci';
+    const test_set_collo = 'latin1_general_ci';
    charsetTest(test_set, test_collo, test_set_str, test_set_collo, done);
  });
@ -112,14 +112,14 @@ describe('connections', function() {
  describe('lazyConnect', function() {
    it('should skip connect phase (lazyConnect = true)', function(done) {
-      var dbConfig = {
+      const dbConfig = {
        host: '127.0.0.1',
        port: 4,
        lazyConnect: true,
      };
-      var ds = new DataSource(mysqlConnector, dbConfig);
+      const ds = new DataSource(mysqlConnector, dbConfig);
-      var errTimeout = setTimeout(function() {
+      const errTimeout = setTimeout(function() {
        done();
      }, 2000);
      ds.on('error', function(err) {
@ -129,12 +129,12 @@ describe('connections', function() {
    });
    it('should report connection error (lazyConnect = false)', function(done) {
-      var dbConfig = {
+      const dbConfig = {
        host: '127.0.0.1',
        port: 4,
        lazyConnect: false,
      };
-      var ds = new DataSource(mysqlConnector, dbConfig);
+      const ds = new DataSource(mysqlConnector, dbConfig);
      ds.on('error', function(err) {
        err.message.should.containEql('ECONNREFUSED');
@ -152,7 +152,7 @@ function charsetTest(test_set, test_collo, test_set_str, test_set_collo, done) {
        createDatabase: true});
      DummyModel = db.define('DummyModel', {string: String});
      db.automigrate(function() {
-        var q = 'SELECT DEFAULT_COLLATION_NAME' +
+        const q = 'SELECT DEFAULT_COLLATION_NAME' +
          ' FROM information_schema.SCHEMATA WHERE SCHEMA_NAME = ' +
          db.driver.escape(db.settings.database) + ' LIMIT 1';
        db.connector.execute(q, function(err, r) {
@ -160,8 +160,8 @@ function charsetTest(test_set, test_collo, test_set_str, test_set_collo, done) {
          should(r[0].DEFAULT_COLLATION_NAME).match(test_collo);
          db.connector.execute('SHOW VARIABLES LIKE "character_set%"', function(err, r) {
            assert.ok(!err);
-            var hit_all = 0;
+            let hit_all = 0;
-            for (var result in r) {
+            for (const result in r) {
              hit_all += matchResult(r[result], 'character_set_connection', test_set);
              hit_all += matchResult(r[result], 'character_set_database', test_set);
              hit_all += matchResult(r[result], 'character_set_results', test_set);
@ -171,8 +171,8 @@ function charsetTest(test_set, test_collo, test_set_str, test_set_collo, done) {
          });
          db.connector.execute('SHOW VARIABLES LIKE "collation%"', function(err, r) {
            assert.ok(!err);
-            var hit_all = 0;
+            let hit_all = 0;
-            for (var result in r) {
+            for (const result in r) {
              hit_all += matchResult(r[result], 'collation_connection', test_set);
              hit_all += matchResult(r[result], 'collation_database', test_set);
            }
@ -193,12 +193,12 @@ function matchResult(result, variable_name, match) {
  return 0;
 }
-var query = function(sql, cb) {
+function query(sql, cb) {
  odb.connector.execute(sql, cb);
-};
+}
 function generateURL(config) {
-  var urlObj = {
+  const urlObj = {
    protocol: 'mysql',
    auth: config.username || '',
    hostname: config.host,
@ -208,6 +208,6 @@ function generateURL(config) {
  if (config.password) {
    urlObj.auth += ':' + config.password;
  }
-  var formatedUrl = url.format(urlObj);
+  const formatedUrl = url.format(urlObj);
  return formatedUrl;
 }
--- a/test/datatypes.test.js
+++ b/test/datatypes.test.js
@ -5,22 +5,22 @@
 'use strict';
 require('./init.js');
-var assert = require('assert');
+const assert = require('assert');
-var _ = require('lodash');
+const _ = require('lodash');
 const GeoPoint = require('loopback-datasource-juggler').GeoPoint;
-var db, BlobModel, EnumModel, ANIMAL_ENUM, City, Account;
+let db, BlobModel, EnumModel, ANIMAL_ENUM, City, Account;
-var mysqlVersion;
+let mysqlVersion;
 describe('MySQL specific datatypes', function() {
  before(setup);
  describe('Support explicit datatypes on a property', function() {
-    var dateString1 = '2017-04-01';
+    const dateString1 = '2017-04-01';
-    var dateString2 = '2016-01-30';
+    const dateString2 = '2016-01-30';
-    var dateForTransactions = [new Date(dateString1).toString(), new Date(dateString2).toString()];
+    const dateForTransactions = [new Date(dateString1).toString(), new Date(dateString2).toString()];
-    var data = [
+    const data = [
      {
        id: 1,
        type: 'Student - Basic',
@ -111,7 +111,7 @@ describe('MySQL specific datatypes', function() {
    });
    it('update an instance', function(done) {
-      var updatedData = {
+      const updatedData = {
        type: 'Student - Basic',
        amount: 1155.77,
      };
@ -143,7 +143,7 @@ describe('MySQL specific datatypes', function() {
  });
  it('should create a model instance with Enums', function(done) {
-    var em = EnumModel.create({animal: ANIMAL_ENUM.CAT, condition: 'sleepy', mood: 'happy'}, function(err, obj) {
+    const em = EnumModel.create({animal: ANIMAL_ENUM.CAT, condition: 'sleepy', mood: 'happy'}, function(err, obj) {
      if (err) return done(err);
      assert.equal(obj.condition, 'sleepy');
      EnumModel.findOne({where: {animal: ANIMAL_ENUM.CAT}}, function(err, found) {
@ -168,9 +168,9 @@ describe('MySQL specific datatypes', function() {
  });
  it('should create a model instance with object/json types', function(done) {
-    var note = {a: 1, b: '2'};
+    const note = {a: 1, b: '2'};
-    var extras = {c: 3, d: '4'};
+    const extras = {c: 3, d: '4'};
-    var em = EnumModel.create({animal: ANIMAL_ENUM.DOG, condition: 'sleepy',
+    const em = EnumModel.create({animal: ANIMAL_ENUM.DOG, condition: 'sleepy',
      mood: 'happy', note: note, extras: extras}, function(err, obj) {
      if (err) return done(err);
      assert.equal(obj.condition, 'sleepy');
@ -185,9 +185,9 @@ describe('MySQL specific datatypes', function() {
    });
  });
  it('should create a model instance with binary types', function(done) {
-    var str = 'This is a test';
+    const str = 'This is a test';
-    var name = 'bob';
+    const name = 'bob';
-    var bob = {name: name, bin: new Buffer.from(str)};
+    const bob = {name: name, bin: new Buffer.from(str)};
    BlobModel.create(bob, function(err, obj) {
      if (err) return done(err);
      assert.equal(obj.bin.toString(), str);
@ -199,20 +199,20 @@ describe('MySQL specific datatypes', function() {
    });
  });
  it('should create a model instance with geopoint type', function(done) {
-    var city1 = {
+    const city1 = {
      name: 'North York',
      loc: {
        lat: 43.761539,
        lng: -79.411079,
      },
    };
-    var xcor, ycor;
+    let xcor, ycor;
    City.create(city1, function(err, res) {
      if (err) return done(err);
      const loc_in_geo_type = new GeoPoint(city1.loc);
      res.loc.should.deepEqual(loc_in_geo_type);
      res.name.should.equal(city1.name);
-      var sqlStmt = 'select ST_X(loc),ST_Y(loc) from City where id=1';
+      const sqlStmt = 'select ST_X(loc),ST_Y(loc) from City where id=1';
      db.connector.execute(sqlStmt, function(err, res) {
        if (err) return done(err);
        xcor = res[0]['ST_X(loc)'];
@ -262,16 +262,16 @@ function setup(done) {
  });
 }
-var query = function(sql, cb) {
+function query(sql, cb) {
  db.adapter.execute(sql, cb);
-};
+}
-var blankDatabase = function(db, cb) {
+function blankDatabase(db, cb) {
-  var dbn = db.settings.database;
+  const dbn = db.settings.database;
-  var cs = db.settings.charset;
+  const cs = db.settings.charset;
-  var co = db.settings.collation;
+  const co = db.settings.collation;
  query('DROP DATABASE IF EXISTS ' + dbn, function(err) {
-    var q = 'CREATE DATABASE ' + dbn;
+    let q = 'CREATE DATABASE ' + dbn;
    if (cs) {
      q += ' CHARACTER SET ' + cs;
    }
@ -282,36 +282,4 @@ var blankDatabase = function(db, cb) {
      query('USE ' + dbn, cb);
    });
  });
-};
+}
 var getFields = function(model, cb) {
  query('SHOW FIELDS FROM ' + model, function(err, res) {
    if (err) {
      cb(err);
    } else {
      var fields = {};
      res.forEach(function(field) {
        fields[field.Field] = field;
      });
      cb(err, fields);
    }
  });
 };
 var getIndexes = function(model, cb) {
  query('SHOW INDEXES FROM ' + model, function(err, res) {
    if (err) {
      console.log(err);
      cb(err);
    } else {
      var indexes = {};
      // Note: this will only show the first key of compound keys
      res.forEach(function(index) {
        if (parseInt(index.Seq_in_index, 10) == 1) {
          indexes[index.Key_name] = index;
        }
      });
      cb(err, indexes);
    }
  });
 };
--- a/test/datetime.test.js
+++ b/test/datetime.test.js
@ -5,13 +5,13 @@
 'use strict';
-var DateString = require('../node_modules/loopback-datasource-juggler/lib/date-string');
+const DateString = require('../node_modules/loopback-datasource-juggler/lib/date-string');
-var fmt = require('util').format;
+const fmt = require('util').format;
-var should = require('./init.js');
+const should = require('./init.js');
-var db, Person;
+let db, Person;
 describe('MySQL datetime handling', function() {
-  var personDefinition = {
+  const personDefinition = {
    name: String,
    gender: String,
    married: Boolean,
@ -47,7 +47,7 @@ describe('MySQL datetime handling', function() {
  });
  it('should allow use of DateStrings', () => {
-    var d = new DateString('1971-06-22');
+    const d = new DateString('1971-06-22');
    return Person.create({
      name: 'Mr. Pink',
      gender: 'M',
@ -63,7 +63,7 @@ describe('MySQL datetime handling', function() {
  });
  describe('should allow use of alternate timezone settings', function() {
-    var d = new Date('1971-06-22T00:00:00.000Z');
+    const d = new Date('1971-06-22T00:00:00.000Z');
    testDateTime(d, '+04:00', '1971-06-22 04:00:00');
    testDateTime(d, '-04:00', '1971-06-21 20:00:00');
    testDateTime(d, '-11:00', '1971-06-21 13:00:00');
@ -74,7 +74,7 @@ describe('MySQL datetime handling', function() {
        setConnectionTimezones(tz);
        db.settings.legacyUtcDateProcessing = false;
        db.settings.timezone = tz;
-        var dt = new Date(date);
+        const dt = new Date(date);
        return Person.create({
          name: 'Mr. Pink',
          gender: 'M',
@ -90,7 +90,7 @@ describe('MySQL datetime handling', function() {
  });
  it('should allow use of fractional seconds', function() {
-    var d = new Date('1971-06-22T12:34:56.789Z');
+    const d = new Date('1971-06-22T12:34:56.789Z');
    return Person.create({
      name: 'Mr. Pink',
      gender: 'M',
@ -99,7 +99,7 @@ describe('MySQL datetime handling', function() {
      return Person.findById(inst.id);
    }).then(function(inst) {
      inst.should.not.eql(null);
-      var lastLogon = new Date(inst.lastLogon);
+      const lastLogon = new Date(inst.lastLogon);
      lastLogon.toJSON().should.eql(d.toJSON());
      return;
    });
--- a/test/init.js
+++ b/test/init.js
@ -9,9 +9,9 @@ module.exports = require('should');
 const juggler = require('loopback-datasource-juggler');
 let DataSource = juggler.DataSource;
-var config = require('rc')('loopback', {test: {mysql: {}}}).test.mysql;
+const config = require('rc')('loopback', {test: {mysql: {}}}).test.mysql;
 global.getConfig = function(options) {
-  var dbConf = {
+  const dbConf = {
    host: process.env.MYSQL_HOST || config.host || 'localhost',
    port: process.env.MYSQL_PORT || config.port || 3306,
    database: process.env.MYSQL_DATABASE || 'myapp_test',
@ -21,7 +21,7 @@ global.getConfig = function(options) {
  };
  if (options) {
-    for (var el in options) {
+    for (const el in options) {
      dbConf[el] = options[el];
    }
  }
--- a/test/migration.test.js
+++ b/test/migration.test.js
@ -4,14 +4,14 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var assert = require('assert');
+const assert = require('assert');
-var async = require('async');
+const async = require('async');
-var platform = require('./helpers/platform');
+const platform = require('./helpers/platform');
-var should = require('./init');
+const should = require('./init');
-var Schema = require('loopback-datasource-juggler').Schema;
+const Schema = require('loopback-datasource-juggler').Schema;
-var db, UserData, StringData, NumberData, DateData, DefaultData, SimpleEmployee;
+let db, UserData, StringData, NumberData, DateData, DefaultData, SimpleEmployee;
-var mysqlVersion;
+let mysqlVersion;
 describe('migrations', function() {
  before(setup);
@ -263,7 +263,7 @@ describe('migrations', function() {
    if (platform.isWindows) {
      return done();
    }
-    var userExists = function(cb) {
+    const userExists = function(cb) {
      query('SELECT * FROM UserData', function(err, res) {
        cb(!err && res[0].email == 'test@example.com');
      });
@ -338,7 +338,8 @@ describe('migrations', function() {
          assert.equal(found.floater, 12345678.123456);
          done();
        });
-      });
+      },
    );
  });
  // Reference: http://dev.mysql.com/doc/refman/5.7/en/out-of-range-and-overflow.html
@ -377,7 +378,7 @@ describe('migrations', function() {
    DefaultData.create({}, function(err, obj) {
      assert.ok(!err);
      assert.ok(obj);
-      var now = new Date();
+      const now = new Date();
      DefaultData.findById(obj.id, function(err, found) {
        now.setSeconds(0);
        found.dateTime.setSeconds(0);
@ -501,7 +502,7 @@ describe('migrations', function() {
    query('INSERT INTO `DateData` ' +
      '(`dateTime`, `timestamp`) ' +
      'VALUES("0000-00-00 00:00:00", "0000-00-00 00:00:00") ', function(err) {
-      var errMsg = 'ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: ' +
+      const errMsg = 'ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: ' +
          '\'0000-00-00 00:00:00\' for column \'dateTime\' at row 1';
      assert(err);
      assert.equal(err.message, errMsg);
@ -517,7 +518,7 @@ describe('migrations', function() {
    query('INSERT INTO `DateData` ' +
      '(`dateTime`, `timestamp`) ' +
      'VALUES("1000-01-01 00:00:00", "0000-00-00 00:00:00") ', function(err) {
-      var errMsg = 'ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: ' +
+      const errMsg = 'ER_TRUNCATED_WRONG_VALUE: Incorrect datetime value: ' +
            '\'0000-00-00 00:00:00\' for column \'timestamp\' at row 1';
      assert(err);
      assert.equal(err.message, errMsg);
@ -608,16 +609,16 @@ function setup(done) {
  });
 }
-var query = function(sql, cb) {
+function query(sql, cb) {
  db.adapter.execute(sql, cb);
-};
+}
-var blankDatabase = function(db, cb) {
+function blankDatabase(db, cb) {
-  var dbn = db.settings.database;
+  const dbn = db.settings.database;
-  var cs = db.settings.charset;
+  const cs = db.settings.charset;
-  var co = db.settings.collation;
+  const co = db.settings.collation;
  query('DROP DATABASE IF EXISTS ' + dbn, function(err) {
-    var q = 'CREATE DATABASE ' + dbn;
+    let q = 'CREATE DATABASE ' + dbn;
    if (cs) {
      q += ' CHARACTER SET ' + cs;
    }
@ -628,14 +629,14 @@ var blankDatabase = function(db, cb) {
      query('USE ' + dbn, cb);
    });
  });
-};
+}
-var getFields = function(model, cb) {
+function getFields(model, cb) {
  query('SHOW FIELDS FROM ' + model, function(err, res) {
    if (err) {
      cb(err);
    } else {
-      var fields = {};
+      const fields = {};
      res.forEach(function(field) {
        fields[field.Field] = field;
      });
@ -644,15 +645,15 @@ var getFields = function(model, cb) {
      cb(err, JSON.parse(JSON.stringify(fields)));
    }
  });
-};
+}
-var getIndexes = function(model, cb) {
+function getIndexes(model, cb) {
  query('SHOW INDEXES FROM ' + model, function(err, res) {
    if (err) {
      console.log(err);
      cb(err);
    } else {
-      var indexes = {};
+      const indexes = {};
      // Note: this will only show the first key of compound keys
      res.forEach(function(index) {
        if (parseInt(index.Seq_in_index, 10) == 1) {
@ -662,4 +663,4 @@ var getIndexes = function(model, cb) {
      cb(err, indexes);
    }
  });
-};
+}
--- a/test/mysql.autoupdate.test.js
+++ b/test/mysql.autoupdate.test.js
@ -4,9 +4,9 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var assert = require('assert');
+const assert = require('assert');
 require('./init');
-var ds;
+let ds;
 before(function() {
  ds = global.getDataSource();
@ -19,7 +19,7 @@ describe('MySQL connector', function() {
  describe('escape index names upon automigrate', function() {
    before(function(done) {
-      var messageSchema = {
+      const messageSchema = {
        'name': 'Message',
        'options': {
          'idInjection': false,
@ -68,7 +68,7 @@ describe('MySQL connector', function() {
  });
  it('should auto migrate/update tables', function(done) {
-    var schema_v1 = {
+    const schema_v1 = {
      'name': 'CustomerTest',
      'options': {
        'idInjection': false,
@ -123,7 +123,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v2 = {
+    const schema_v2 = {
      'name': 'CustomerTest',
      'options': {
        'idInjection': false,
@ -222,7 +222,7 @@ describe('MySQL connector', function() {
        assert(isActual, 'isActual should return true after automigrate');
        ds.discoverModelProperties('customer_test', function(err, props) {
          assert.equal(props.length, 5);
-          var names = props.map(function(p) {
+          const names = props.map(function(p) {
            return p.columnName;
          });
          assert.equal(props[0].nullable, 'N');
@ -250,7 +250,7 @@ describe('MySQL connector', function() {
                ds.discoverModelProperties('customer_test', function(err, props) {
                  if (err) return done(err);
                  assert.equal(props.length, 7);
-                  var names = props.map(function(p) {
+                  const names = props.map(function(p) {
                    return p.columnName;
                  });
                  assert.equal(names[0], 'id');
@ -287,7 +287,7 @@ describe('MySQL connector', function() {
  });
  it('should auto migrate/update foreign keys in tables', function(done) {
-    var customer2_schema = {
+    const customer2_schema = {
      'name': 'CustomerTest2',
      'options': {
        'idInjection': false,
@ -318,7 +318,7 @@ describe('MySQL connector', function() {
        },
      },
    };
-    var customer3_schema = {
+    const customer3_schema = {
      'name': 'CustomerTest3',
      'options': {
        'idInjection': false,
@ -350,7 +350,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v1 = {
+    const schema_v1 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -385,7 +385,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v2 = {
+    const schema_v2 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -423,7 +423,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v3 = {
+    const schema_v3 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -453,7 +453,7 @@ describe('MySQL connector', function() {
      },
    };
-    var foreignKeySelect =
+    const foreignKeySelect =
      'SELECT COLUMN_NAME,CONSTRAINT_NAME,REFERENCED_TABLE_NAME, REFERENCED_COLUMN_NAME ' +
      'FROM   INFORMATION_SCHEMA.KEY_COLUMN_USAGE ' +
      'WHERE  REFERENCED_TABLE_SCHEMA = "myapp_test" ' +
@ -537,7 +537,7 @@ describe('MySQL connector', function() {
  });
  it('should auto migrate/update foreign keys in tables multiple times without error', function(done) {
-    var customer3_schema = {
+    const customer3_schema = {
      'name': 'CustomerTest3',
      'options': {
        'idInjection': false,
@ -569,7 +569,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v1 = {
+    const schema_v1 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -621,7 +621,7 @@ describe('MySQL connector', function() {
  });
  it('should auto migrate/update foreign keys with onUpdate and onDelete in tables', function(done) {
-    var customer2_schema = {
+    const customer2_schema = {
      'name': 'CustomerTest2',
      'options': {
        'idInjection': false,
@ -653,7 +653,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v1 = {
+    const schema_v1 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -690,7 +690,7 @@ describe('MySQL connector', function() {
      },
    };
-    var schema_v2 = {
+    const schema_v2 = {
      'name': 'OrderTest',
      'options': {
        'idInjection': false,
@ -727,12 +727,12 @@ describe('MySQL connector', function() {
      },
    };
-    var foreignKeySelect =
+    const foreignKeySelect =
    'SELECT COLUMN_NAME,CONSTRAINT_NAME,REFERENCED_TABLE_NAME, REFERENCED_COLUMN_NAME ' +
    'FROM   INFORMATION_SCHEMA.KEY_COLUMN_USAGE ' +
    'WHERE  REFERENCED_TABLE_SCHEMA = "myapp_test" ' +
    'AND   TABLE_NAME = "order_test"';
-    var getCreateTable = 'SHOW CREATE TABLE `myapp_test`.`order_test`';
+    const getCreateTable = 'SHOW CREATE TABLE `myapp_test`.`order_test`';
    ds.createModel(customer2_schema.name, customer2_schema.properties, customer2_schema.options);
    ds.createModel(schema_v1.name, schema_v1.properties, schema_v1.options);
@ -789,7 +789,7 @@ describe('MySQL connector', function() {
  });
  function setupAltColNameData() {
-    var schema = {
+    const schema = {
      name: 'ColRenameTest',
      options: {
        idInjection: false,
@ -845,7 +845,7 @@ describe('MySQL connector', function() {
  it('should update the nullable property of "first_name" to false', function(done) {
    // update the model "required" property
-    var schema = {
+    const schema = {
      name: 'ColRenameTest',
      options: {
        idInjection: false,
--- a/test/mysql.discover.test.js
+++ b/test/mysql.discover.test.js
@ -5,11 +5,11 @@
 'use strict';
 process.env.NODE_ENV = 'test';
-var should = require('should');
+const should = require('should');
-var assert = require('assert');
+const assert = require('assert');
-var DataSource = require('loopback-datasource-juggler').DataSource;
+const DataSource = require('loopback-datasource-juggler').DataSource;
-var db, config;
+let db, config;
 before(function(done) {
  require('./init');
@ -42,7 +42,7 @@ describe('discoverModels', function() {
          console.error(err);
          done(err);
        } else {
-          var views = false;
+          let views = false;
          assert(models.length > 0, 'some models returned');
          models.forEach(function(m) {
            if (m.type === 'view') {
@ -66,7 +66,7 @@ describe('discoverModels', function() {
          console.error(err);
          done(err);
        } else {
-          var views = false;
+          const views = false;
          assert(models.length > 0, 'some models returned');
          models.forEach(function(m) {
            assert.equal(m.owner.toLowerCase(), config.database.toLowerCase());
@ -109,7 +109,7 @@ describe('Discover models including other users', function() {
        console.error(err);
        done(err);
      } else {
-        var others = false;
+        let others = false;
        assert.equal(3, models.length);
        models.forEach(function(m) {
          assert(m.owner);
@ -227,7 +227,7 @@ describe('Discover model generated columns', function() {
 });
 describe('Discover LDL schema from a table', function() {
-  var schema;
+  let schema;
  before(function(done) {
    db.discoverSchema('INVENTORY', {owner: 'STRONGLOOP'}, function(err, schema_) {
      schema = schema_;
@ -235,8 +235,8 @@ describe('Discover LDL schema from a table', function() {
    });
  });
  it('should return an LDL schema for INVENTORY', function() {
-    var productId = 'productId' in schema.properties ? 'productId' : 'productid';
+    const productId = 'productId' in schema.properties ? 'productId' : 'productid';
-    var locationId = 'locationId' in schema.properties ? 'locationId' : 'locationid';
+    const locationId = 'locationId' in schema.properties ? 'locationId' : 'locationid';
    assert.strictEqual(schema.name, 'Inventory');
    assert.ok(/STRONGLOOP/i.test(schema.options.mysql.schema));
    assert.strictEqual(schema.options.mysql.table, 'INVENTORY');
@ -257,7 +257,7 @@ describe('Discover LDL schema from a table', function() {
 });
 describe('Discover and build models', function() {
-  var models;
+  let models;
  before(function(done) {
    db.discoverAndBuildModels('INVENTORY', {owner: 'STRONGLOOP', visited: {}, associations: true},
      function(err, models_) {
@ -267,9 +267,9 @@ describe('Discover and build models', function() {
  });
  it('should discover and build models', function() {
    assert(models.Inventory, 'Inventory model should be discovered and built');
-    var schema = models.Inventory.definition;
+    const schema = models.Inventory.definition;
-    var productId = 'productId' in schema.properties ? 'productId' : 'productid';
+    const productId = 'productId' in schema.properties ? 'productId' : 'productid';
-    var locationId = 'locationId' in schema.properties ? 'locationId' : 'locationid';
+    const locationId = 'locationId' in schema.properties ? 'locationId' : 'locationid';
    assert(/STRONGLOOP/i.test(schema.settings.mysql.schema));
    assert.strictEqual(schema.settings.mysql.table, 'INVENTORY');
    assert(schema.properties[productId]);
@ -293,7 +293,7 @@ describe('Discover and build models', function() {
  describe('discoverModelProperties() flags', function() {
    context('with default flags', function() {
-      var models, schema;
+      let models, schema;
      before(discoverAndBuildModels);
      it('handles CHAR(1) as Boolean', function() {
@ -325,7 +325,7 @@ describe('Discover and build models', function() {
    });
    context('with flag treatCHAR1AsString = true', function() {
-      var models, schema;
+      let models, schema;
      before(discoverAndBuildModels);
      it('handles CHAR(1) as String', function() {
@ -358,7 +358,7 @@ describe('Discover and build models', function() {
    });
    context('with flag treatBIT1AsBit = false', function() {
-      var models, schema;
+      let models, schema;
      before(discoverAndBuildModels);
      it('handles CHAR(1) as Boolean', function() {
@ -391,7 +391,7 @@ describe('Discover and build models', function() {
    });
    context('with flag treatTINYINT1AsTinyInt = false', function() {
-      var models, schema;
+      let models, schema;
      before(discoverAndBuildModels);
      it('handles CHAR(1) as Boolean', function() {
--- a/test/mysql.test.js
+++ b/test/mysql.test.js
@ -4,12 +4,12 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var async = require('async');
+const async = require('async');
-var should = require('./init.js');
+const should = require('./init.js');
-var sinon = require('sinon');
+const sinon = require('sinon');
 const List = require('loopback-datasource-juggler/lib/list');
-var Post, PostWithStringId, PostWithUniqueTitle, PostWithNumId, Student, db;
+let Post, PostWithStringId, PostWithUniqueTitle, PostWithNumId, Student, db;
 // Mock up mongodb ObjectID
 function ObjectID(id) {
@ -72,7 +72,8 @@ describe('mysql', function() {
      function(err) {
        should.not.exist(err);
        done(err);
-      });
+      },
    );
  });
  beforeEach(function() {
@ -98,7 +99,7 @@ describe('mysql', function() {
  });
  it('should allow ObjectID', function(done) {
-    var uid = new ObjectID('123');
+    const uid = new ObjectID('123');
    Post.create({title: 'a', content: 'AAA', userId: uid},
      function(err, post) {
        should.not.exist(err);
@ -155,7 +156,7 @@ describe('mysql', function() {
  });
  it('updateOrCreate should create a new instance if it does not exist', function(done) {
-    var post = {id: 123, title: 'a', content: 'AAA'};
+    const post = {id: 123, title: 'a', content: 'AAA'};
    Post.updateOrCreate(post, function(err, p) {
      should.not.exist(err);
      p.title.should.be.equal(post.title);
@ -227,7 +228,7 @@ describe('mysql', function() {
    });
    it('should create a new instance if it does not exist', function(done) {
-      var post = {id: 123, title: 'a', content: 'AAA'};
+      const post = {id: 123, title: 'a', content: 'AAA'};
      Post.replaceOrCreate(post, function(err, p) {
        if (err) return done(err);
        p.id.should.equal(post.id);
@ -246,10 +247,10 @@ describe('mysql', function() {
    });
    it('isNewInstance should be undefined for after save hook', function(done) {
-      var student = {name: 'Joe', age: 20};
+      const student = {name: 'Joe', age: 20};
-      var newStudent = {};
+      const newStudent = {};
-      var isNewInstanceBefore = false;
+      let isNewInstanceBefore = false;
-      var isNewInstanceAfter = false;
+      let isNewInstanceAfter = false;
      Student.create(student, function(err, createdStudent) {
        if (err) return done(err);
        newStudent.id = createdStudent.id;
@ -314,7 +315,7 @@ describe('mysql', function() {
    });
  it('save should create a new instance if it does not exist', function(done) {
-    var post = new Post({id: 123, title: 'a', content: 'AAA'});
+    const post = new Post({id: 123, title: 'a', content: 'AAA'});
    post.save(post, function(err, p) {
      should.not.exist(err);
      p.title.should.be.equal(post.title);
@ -335,7 +336,7 @@ describe('mysql', function() {
  });
  it('all return should honor filter.fields', function(done) {
-    var post = new Post({title: 'b', content: 'BBB'});
+    const post = new Post({title: 'b', content: 'BBB'});
    post.save(function(err, post) {
      Post.all({fields: ['title'], where: {title: 'b'}}, function(err, posts) {
        should.not.exist(err);
@ -468,7 +469,7 @@ describe('mysql', function() {
    });
  });
  context('null vals in different operators', function() {
-    var defaultPost = {
+    const defaultPost = {
      id: 3,
      title: 'defTitle',
      content: 'defContent',
@ -689,7 +690,7 @@ describe('mysql', function() {
  });
  it('should not allow duplicate titles', function(done) {
-    var data = {title: 'a', content: 'AAA'};
+    const data = {title: 'a', content: 'AAA'};
    PostWithUniqueTitle.create(data, function(err, post) {
      should.not.exist(err);
      PostWithUniqueTitle.create(data, function(err, post) {
@ -729,7 +730,7 @@ describe('mysql', function() {
        beforeEach(function addSpy() {
          sinon.stub(console, 'warn');
        });
-        afterEach(function removeSpy()  {
+        afterEach(function removeSpy() {
          console.warn.restore();
        });
@ -793,7 +794,7 @@ describe('mysql', function() {
        beforeEach(function addSpy() {
          sinon.stub(console, 'warn');
        });
-        afterEach(function removeSpy()  {
+        afterEach(function removeSpy() {
          console.warn.restore();
        });
@ -846,7 +847,7 @@ describe('mysql', function() {
      beforeEach(function addSpy() {
        sinon.stub(console, 'warn');
      });
-      afterEach(function removeSpy()  {
+      afterEach(function removeSpy() {
        console.warn.restore();
      });
--- a/test/set-http-code.test.js
+++ b/test/set-http-code.test.js
@ -5,8 +5,8 @@
 'use strict';
-var setHttpCode = require('../lib/set-http-code');
+const setHttpCode = require('../lib/set-http-code');
-var should = require('./init.js');
+const should = require('./init.js');
 describe('setHttpCode', function() {
  describe('should set statusCode', function() {
@ -22,7 +22,7 @@ describe('setHttpCode', function() {
    function testErrorCode(name, msg, expected) {
      it(name, function() {
-        var err = new Error(msg);
+        let err = new Error(msg);
        err = setHttpCode(err);
        should.exist(err.statusCode);
        should.equal(err.statusCode, expected);
@ -34,7 +34,7 @@ describe('setHttpCode', function() {
  });
  it('should convert strings to errors', function() {
-    var err = 'REALLY_BAD: Something truly awful occurred.';
+    let err = 'REALLY_BAD: Something truly awful occurred.';
    err = setHttpCode(err);
    should.exist(err.statusCode);
    should(err instanceof Error);
--- a/test/transaction.promise.test.js
+++ b/test/transaction.promise.test.js
@ -7,11 +7,11 @@
 if (typeof Promise === 'undefined') {
  global.Promise = require('bluebird');
 }
-var Transaction = require('loopback-datasource-juggler').Transaction;
+const Transaction = require('loopback-datasource-juggler').Transaction;
 require('./init.js');
 require('should');
-var db, Post, Review;
+let db, Post, Review;
 describe('transactions with promise', function() {
  before(function(done) {
@ -38,13 +38,13 @@ describe('transactions with promise', function() {
    done();
  });
-  var currentTx;
+  let currentTx;
-  var hooks = [];
+  let hooks = [];
  // Return an async function to start a transaction and create a post
  function createPostInTx(post, timeout) {
    return function(done) {
      // Transaction.begin(db.connector, Transaction.READ_COMMITTED,
-      var promise = Post.beginTransaction({
+      const promise = Post.beginTransaction({
        isolationLevel: Transaction.READ_COMMITTED,
        timeout: timeout,
      });
@ -77,8 +77,10 @@ describe('transactions with promise', function() {
            }, {transaction: currentTx}).then(
              function(c) {
                done(null, c);
-              });
+              },
-          });
+            );
          },
        );
      }).catch(done);
    };
  }
@ -87,7 +89,7 @@ describe('transactions with promise', function() {
  // records to equal to the count
  function expectToFindPosts(where, count, inTx) {
    return function(done) {
-      var options = {};
+      const options = {};
      if (inTx) {
        options.transaction = currentTx;
      }
@ -105,12 +107,13 @@ describe('transactions with promise', function() {
          } else {
            done();
          }
-        }).catch(done);
+        },
      ).catch(done);
    };
  }
  describe('commit', function() {
-    var post = {title: 't1', content: 'c1'};
+    const post = {title: 't1', content: 'c1'};
    before(createPostInTx(post));
    it('should not see the uncommitted insert', expectToFindPosts(post, 0));
@ -136,7 +139,7 @@ describe('transactions with promise', function() {
  });
  describe('rollback', function() {
-    var post = {title: 't2', content: 'c2'};
+    const post = {title: 't2', content: 'c2'};
    before(createPostInTx(post));
    it('should not see the uncommitted insert', expectToFindPosts(post, 0));
@ -162,7 +165,7 @@ describe('transactions with promise', function() {
  });
  describe('timeout', function() {
-    var post = {title: 't3', content: 'c3'};
+    const post = {title: 't3', content: 'c3'};
    before(createPostInTx(post, 500));
    it('should invoke the timeout hook', function(done) {
--- a/test/transaction.test.js
+++ b/test/transaction.test.js
@ -4,11 +4,11 @@
 // License text available at https://opensource.org/licenses/MIT
 'use strict';
-var Transaction = require('loopback-datasource-juggler').Transaction;
+const Transaction = require('loopback-datasource-juggler').Transaction;
 require('./init.js');
 require('should');
-var db, Post, Review;
+let db, Post, Review;
 describe('transactions', function() {
  before(function(done) {
@ -28,8 +28,8 @@ describe('transactions', function() {
    });
  });
-  var currentTx;
+  let currentTx;
-  var hooks = [];
+  let hooks = [];
  // Return an async function to start a transaction and create a post
  function createPostInTx(post, timeout) {
    return function(done) {
@ -81,7 +81,7 @@ describe('transactions', function() {
  // records to equal to the count
  function expectToFindPosts(where, count, inTx) {
    return function(done) {
-      var options = {};
+      const options = {};
      if (inTx) {
        options.transaction = currentTx;
      }
@ -106,7 +106,7 @@ describe('transactions', function() {
  }
  describe('commit', function() {
-    var post = {title: 't1', content: 'c1'};
+    const post = {title: 't1', content: 'c1'};
    before(createPostInTx(post));
    it('should not see the uncommitted insert', expectToFindPosts(post, 0));
@ -132,7 +132,7 @@ describe('transactions', function() {
  });
  describe('rollback', function() {
-    var post = {title: 't2', content: 'c2'};
+    const post = {title: 't2', content: 'c2'};
    before(createPostInTx(post));
    it('should not see the uncommitted insert', expectToFindPosts(post, 0));
@ -158,7 +158,7 @@ describe('transactions', function() {
  });
  describe('timeout', function() {
-    var post = {title: 't3', content: 'c3'};
+    const post = {title: 't3', content: 'c3'};
    before(createPostInTx(post, 500));
    it('should invoke the timeout hook', function(done) {