Improve async usage

index.js

@@ -25,7 +25,7 @@ module.exports = (config,logger) => {
       const xml = xmlbuilder.create('Package')
       .att('xmlns', 'http://soap.sforce.com/2006/04/metadata')
       .dec('1.0', 'UTF-8');
-      result.forEach(elem => xml.importDocument(elem));
+      result.forEach(elem => {if(!!elem) xml.importDocument(elem)});
       xml.ele('version')
       .t(config.apiVersion);
       const xmlContent = xml.end({ pretty: true, indent: '  ', newline: '\n' });

lib/factories/type-strategy-factory.js

@@ -5,7 +5,7 @@ const metadata = require('../utils/metadata');
 
 // TODO CustomObject
 // TODO Workflow
-// TODO email template and report dashboard
+// TODO email template and report dashboard and Document
 
 const classes = {
   'CustomLabels' : CustomLabels

lib/strategies/type-strategies/customlabel-type-strategy.js

@@ -1,7 +1,7 @@
 const metadata = require('../../utils/metadata');
 const xmlbuilder = require('xmlbuilder');
 const xml2jsAsync = require('../../utils/async-xml-parser');
-const fs = require('fs');
+const readFileAsync = require('../../utils/async-read-file')
 const AbstractTypeStrategy = require('./standard-type-strategy');
 
 module.exports = class CustomLabelStrategy extends AbstractTypeStrategy {
@@ -11,25 +11,28 @@ module.exports = class CustomLabelStrategy extends AbstractTypeStrategy {
 
   build(){
     const promise = new Promise((resolve, reject) => {
-      if(this.child.children.length > 0) {
-        const type = xmlbuilder.create('types');
-        Promise.all(
-          this.child.children
-          .sort((a,b) => a.name.localeCompare(b.name))
-          .map( aCustomLabelNode => fs.readFileSync(aCustomLabelNode.path,"utf8"))
-          .map(xml2jsAsync)
-        ).then(result => {
-          result.forEach( customLabelFile =>
-            customLabelFile.CustomLabels.labels.forEach(customLabelDefinition => {
-              type.ele('members')
-              .t(customLabelDefinition.fullName[0]);
-            })
-          )        
-        }).then(()=> {
-          type.ele('name').t(metadata[this.child.name].children[metadata[this.child.name].xmlName]);
-          resolve(type);
-        }).catch(reject);
+      if(this.child.children.length == 0) {
+        resolve();
       }
+      Promise.all(
+        this.child.children
+        .sort((a,b) => a.name.localeCompare(b.name))
+        .map( aCustomLabelNode => readFileAsync(aCustomLabelNode.path,'utf8').then(xml2jsAsync))
+      ).then(result => {
+        let isEmpty = true;
+        const type = xmlbuilder.create('types');
+        result.forEach( customLabelFile => {
+          const customLabelDefinitions = customLabelFile.CustomLabels.labels
+          .sort((a,b) => a.fullName[0].localeCompare(b.fullName[0]));
+          isEmpty &= customLabelDefinitions.length == 0;
+          customLabelDefinitions.forEach(customLabelDefinition => {
+            type.ele('members')
+            .t(customLabelDefinition.fullName[0]);
+          })
+        })
+        type.ele('name').t(metadata[this.child.name].children[metadata[this.child.name].xmlName]);
+        resolve(isEmpty ? undefined : type);
+      }).catch(reject);
     });
     return promise;
   }

lib/strategies/type-strategies/standard-type-strategy.js

@@ -8,13 +8,12 @@ module.exports = class StandardStrategy {
 
   build(){
     const promise = new Promise((resolve, reject) => {
-      if(this.child.children.length == 0) {
+      const children = this.child.children.filter(elem => elem.extension && elem.extension != '.xml' && !elem.name.startsWith('.'))
+      if(children.length == 0) {
         resolve();
       }
       const type = xmlbuilder.create('types');
-      this.child.children
-      .filter(elem => elem.extension && elem.extension != '.xml' && !elem.name.startsWith('.'))
-      .sort((a,b) => a.name.localeCompare(b.name))
+      children.sort((a,b) => a.name.localeCompare(b.name))
       .forEach(subChild => {
         type.ele('members')
         .t(subChild.name.replace(/\.[^/.]+$/,''));

lib/utils/async-read-file.js

@@ -0,0 +1,12 @@
+const fs = require('fs');
+
+const readFileAsync = (path) => {
+  const promise = new Promise((resolve, reject) => {
+    fs.readFile(path, (err, data) => {
+      if (err) reject(err);
+      resolve(data);
+    });
+  });
+  return promise;
+};
+module.exports = readFileAsync;

lib/utils/async-xml-parser.js

@@ -1,12 +1,13 @@
 const xml2js = require('xml2js');
 
 const parseStringAsync = (fileContent) => {
-  return new Promise((resolve, reject) => {
+  const promise = new Promise((resolve, reject) => {
     const parser = new xml2js.Parser();
     parser.parseString(fileContent, (err, result) => {
       if (err) reject(err);
       resolve(result);
     });
   });
+  return promise;
 };
 module.exports = parseStringAsync;