Refactor for ES6

.travis.yml

@@ -1,12 +1,12 @@
 language: node_js
 node_js:
-  - 4.2
-  - 6.0
+  - 6.10
+  - 8.10
 jdk:
   - oraclejdk8
 install:
   - mkdir /tmp/dynamodb
-  - wget -O - http://dynamodb-local.s3-website-us-west-2.amazonaws.com/dynamodb_local_latest | tar xz --directory /tmp/dynamodb
+  - wget -O - https://s3-us-west-2.amazonaws.com/dynamodb-local/dynamodb_local_latest.tar.gz | tar xz --directory /tmp/dynamodb
   - npm install
 script: make test-cov
 before_script:

README.md

@@ -10,7 +10,7 @@ DynamoDB processor operates a process by simple JSON expression.
 ## Features
 
 * If it have failed to set child objects to Map Type field, auto trying to update with initial fields again. futhermore, If it have failed by the conflict, auto trying the updating process at first once more.
-* Node.js 4.2 or later
+* Node.js 6.10 or later
 
 ## Install
 

lib/doc_client.js

@@ -1,6 +1,6 @@
 'use strict';
 
-module.exports = function(docClient) {
+module.exports = (docClient) => {
 
   function get(params) {
     return docClient.get(params).promise();
@@ -16,23 +16,19 @@ module.exports = function(docClient) {
 
   function update(params) {
     return docClient.update(params).promise()
-      .then(data => {
-        return data.Attributes;
-      });
+      .then(data => data.Attributes);
   }
 
   function batchWrite(params) {
     return docClient.batchWrite(params).promise()
-      .then(data => {
-        return data.UnprocessedItems;
-      });
+      .then(data => data.UnprocessedItems);
   }
 
   return {
-    get: get,
-    put: put,
-    update: update,
-    batchGet: batchGet,
-    batchWrite: batchWrite,
-  };
+    get,
+    put,
+    update,
+    batchGet,
+    batchWrite
+  }
 }

lib/expression.js

@@ -5,11 +5,12 @@ const AWS = require('aws-sdk');
 const docClient = new AWS.DynamoDB.DocumentClient();
 
 
-function Expression(initFields) {
-  this._initFields = initFields || {};
-}
-Expression.prototype = {
-  generate: function(table, key, ops, withInit) {
+class Expression {
+  constructor(initFields) {
+    this._initFields = initFields || {};
+  }
+
+  generate(table, key, ops, withInit) {
     this._reset();
 
     const init = withInit || false;
@@ -62,8 +63,9 @@ Expression.prototype = {
     }
 
     return result;
-  },
-  _reset: function() {
+  }
+
+  _reset() {
     this._inits = _.cloneDeep(this._initFields);
     this._sets = [];
     this._adds = [];
@@ -73,35 +75,40 @@ Expression.prototype = {
     this._fldIdx = 0;
     this._valIdx = 0;
     this._conds = [];
-  },
-  _addSet: function(name, val, init) {
+  }
+
+  _addSet(name, val, init) {
     if (!init || !this._addInitSet(name, val)) {
       const path = this._registerName(name);
       const i = this._regVal(val);
       this._sets.push(`${path} = :v${i}`);
     }
-  },
-  _addAdd: function(name, val, init) {
+  }
+
+  _addAdd(name, val, init) {
     if (!init || !this._addInitSet(name, val)) {
       const path = this._registerName(name);
       const i = this._regVal(val);
       this._adds.push(`${path} :v${i}`);
     }
-  },
-  _addPushSet: function(name, val, init) {
+  }
+
+  _addPushSet(name, val, init) {
     const valSet = docClient.createSet(val);
 
     if (!init || !this._addInitSet(name, valSet)) {
       const path = this._registerName(name);
       const i = this._regVal(valSet);
       this._adds.push(`${path} :v${i}`);
     }
-  },
-  _addRemove: function(name) {
+  }
+
+  _addRemove(name) {
     const path = this._registerName(name);
     this._removes.push(path);
-  },
-  _addInitSet: function(name, val) {
+  }
+
+  _addInitSet(name, val) {
     const paths = name.split(' ');
     const rootPath = paths[0];
     const initVal = this._inits[rootPath];
@@ -114,20 +121,23 @@ Expression.prototype = {
       initVal.push(val);
     }
     return true;
-  },
-  _registerName: function(name) {
+  }
+
+  _registerName(name) {
     return name.split(' ').map((nm) => {
         const fn = '#f' + ++this._fldIdx;
         this._attrNames[fn] = nm;
         return fn;
       }).join('.');
-  },
-  _regVal: function(val) {
+  }
+
+  _regVal(val) {
     const vi = ++this._valIdx;
     this._attrValues[`:v${vi}`] = val;
     return vi;
-  },
-  _geneInits: function(fields) {
+  }
+
+  _geneInits(fields) {
     for (let field in this._inits) {
       const val = this._inits[field];
       const i = this._regVal(val);
@@ -144,8 +154,9 @@ Expression.prototype = {
         this._conds.push(`attribute_not_exists(${fn})`);
       }
     }
-  },
-  _getExpression: function() {
+  }
+
+  _getExpression() {
     const exp = [];
 
     if (this._sets.length) {

lib/processor.js

@@ -161,7 +161,7 @@ class Processor {
           this.logger.info('Updated %s on %s table', itemKey, table);
           return data;
         })
-        .catch((err) => {
+        .catch(err => {
           if (init && err.code === 'ValidationException'
             && err.message === MSG_INVALID_EXPRESSION) {
 
@@ -211,9 +211,7 @@ class Processor {
         if (useBatch) {
           return this.batchWrite(table, data.items);
         } else {
-          return data.items.map((item) => {
-              return this.put(table, item);
-            });
+          return data.items.map((item) => this.put(table, item));
         }
       }
     } else if (data.action === 'update' || data.set
@@ -233,9 +231,7 @@ class Processor {
         if (useBatch) {
           return this.batchGet(table, data.keys);
         } else {
-          return data.keys.map((key) => {
-              return this.get(table, key);
-            });
+          return data.keys.map((key) => this.get(table, key));
         }
       }
     }