Optimize upload timer.

lib/processMultipart.js

@@ -111,7 +111,7 @@ module.exports = (options, req, res, next) => {
     });
 
     file.on('data', (data) => {
-      uploadTimer.set(); // Refresh upload timer each time new data chunk came.
+      uploadTimer.refresh(); // Refresh upload timer each time new data chunk came.
       dataHandler(data); // Handle new piece of data.
     });
 

lib/uploadtimer.js

@@ -1,24 +1,45 @@
 class UploadTimer {
   /**
    * @constructor
-   * @param {number} timeout - timer timeout in msecs. 
+   * @param {number} timeout - timer timeout in msecs.
    * @param {Function} callback - callback to run when timeout reached.
    */
-  constructor(timeout = 0, callback = () => {}) {
-    this.timeout = timeout;
-    this.callback = callback;
+  constructor(timeout, callback) {
+    this.timeout = timeout || 0;
+    this.callback = callback || (() => {});
     this.timer = null;
   }
 
+  /**
+   * Sets the timer.
+   * Initializes & starts the timer.
+   * @returns {boolean} True if timer has been set.
+   */
+  set() {
+    if (this.timer || !this.timeout) return false;
+    this.timer = setTimeout(() => {
+      this.clear();
+      this.callback();
+    }, this.timeout);
+    return true;
+  }
+
+  /**
+   * Clears the timer.
+   * If timer cleared, it has to be re-initialized again with set method.
+   */
   clear() {
     clearTimeout(this.timer);
   }
 
-  set() {
-    // Do not start a timer if zero timeout or it hasn't been set. 
-    if (!this.timeout) return false;
-    this.clear();
-    this.timer = setTimeout(this.callback, this.timeout);
+  /**
+   * Refreshes timer.
+   * @returns {boolean} True if timer has been refreshed.
+   */
+  refresh() {
+    // Do nothing if zero/empty timeout or timer hasn't been initialized.
+    if (!this.timer) return false;
+    this.timer.refresh();
     return true;
   }
 }