Formatting utilities

Author: RomanBurunkov

lib/utilities.js

@@ -2,7 +2,7 @@
 
 const fs = require('fs');
 const path = require('path');
-const Readable = require('stream').Readable;
+const { Readable } = require('stream');
 
 // Parameters for safe file name parsing.
 const SAFE_FILE_NAME_REGEX = /[^\w-]/g;
@@ -27,17 +27,17 @@ const debugLog = (options, msg) => {
 };
 
 /**
- * Generates unique temporary file name like: tmp-5000-156788789789.
+ * Generates unique temporary file name. e.g. tmp-5000-156788789789.
  * @param {string} prefix - a prefix for generated unique file name.
  * @returns {string}
  */
-const getTempFilename = (prefix) => {
+const getTempFilename = (prefix = TEMP_PREFIX) => {
   tempCounter = tempCounter >= TEMP_COUNTER_MAX ? 1 : tempCounter + 1;
-  return `${prefix || TEMP_PREFIX}-${tempCounter}-${Date.now()}`;
+  return `${prefix}-${tempCounter}-${Date.now()}`;
 };
 
 /**
- * isFunc- check if argument is a function.
+ * isFunc: Checks if argument is a function.
  * @returns {boolean} - Returns true if argument is a function.
  */
 const isFunc = func => func && func.constructor && func.call && func.apply ? true: false;
@@ -60,7 +60,7 @@ const promiseCallback = (resolve, reject) => {
  * Builds instance options from arguments objects(can't be arrow function).
  * @returns {Object} - result options.
  */
-const buildOptions = function(){
+const buildOptions = function() {
   const result = {};
   [...arguments].forEach(options => {
     if (!options || typeof options !== 'object') return;
@@ -107,17 +107,18 @@ const checkAndMakeDir = (fileUploadOptions, filePath) => {
   // Check whether folder for the file exists.
   if (!filePath) return false;
   const parentPath = path.dirname(filePath);
-  // Create folder if it is not exists.
+  // Create folder if it doesn't exist.
   if (!fs.existsSync(parentPath)) fs.mkdirSync(parentPath, { recursive: true }); 
   // Checks folder again and return a results.
   return fs.existsSync(parentPath);
 };
 
 /**
- * Delete file.
+ * Deletes a file.
  * @param {string} file - Path to the file to delete.
+ * @param {Function} callback
  */
-const deleteFile = (file, callback) => fs.unlink(file, err => err ? callback(err) : callback());
+const deleteFile = (file, callback) => fs.unlink(file, callback);
 
 /**
  * Copy file via streams
@@ -147,15 +148,15 @@ const copyFile = (src, dst, callback) => {
 };
 
 /**
- * moveFile - moves the file from src to dst.
+ * moveFile: moves the file from src to dst.
  * Firstly trying to rename the file if no luck copying it to dst and then deleteing src.
  * @param {string} src - Path to the source file
  * @param {string} dst - Path to the destination file.
  * @param {Function} callback - A callback function.
  */
-const moveFile = (src, dst, callback) => fs.rename(src, dst, err => (!err
-  ? callback()
-  : copyFile(src, dst, err => err ? callback(err) : deleteFile(src, callback))
+const moveFile = (src, dst, callback) => fs.rename(src, dst, err => (err
+  ? copyFile(src, dst, err => err ? callback(err) : deleteFile(src, callback))
+  : callback()
 ));
 
 /**
@@ -176,7 +177,7 @@ const saveBufferToFile = (buffer, filePath, callback) => {
   };
   // Setup file system writable stream.
   let fstream = fs.createWriteStream(filePath);
-  fstream.on('error', error => callback(error));
+  fstream.on('error', err => callback(err));
   fstream.on('close', () => callback());
   // Copy file via piping streams.
   readStream.pipe(fstream);
@@ -252,18 +253,18 @@ const parseFileName = (opts, fileName) => {
 };
 
 module.exports = {
-  debugLog,
   isFunc,
+  debugLog,
+  copyFile, // For testing purpose.
+  moveFile,
   errorFunc,
-  promiseCallback,
-  buildOptions,
+  deleteFile, // For testing purpose.
   buildFields,
-  checkAndMakeDir,
-  deleteFile,         // For testing purpose.
-  copyFile,           // For testing purpose.
-  moveFile,
-  saveBufferToFile,
+  buildOptions,
   parseFileName,
   getTempFilename,
+  promiseCallback,
+  checkAndMakeDir,
+  saveBufferToFile,
   uriDecodeFileName
 };