Export syntax in NodeJs

I am new to Node.JS. I am knocking some utility functions for an existing application.
I have added these functions:

 * @returns the current stacktrace
function getStackTrace() {
    var orig = Error.prepareStackTrace;
    Error.prepareStackTrace = function(_, theCallStack) {
        return theCallStack;
    var err = new Error;
    Error.captureStackTrace(err, arguments.callee);
    var stack = err.stack;
    Error.prepareStackTrace = orig;
    return stack;

 * Gets the name of the function which called the function which calls this function.
 * E.g first() calls seconds(), which calls this function; the return value will be the string 'first, since second, 
 * which called this, wants to know who called it.
 * @param[depth] : Optional, default = 1, allows us to examine the call stack at different depths, should we wish to 
exports.getCallingFunctionName = (depth = 1) => {
        const theCallStack = getStackTrace();
        if (depth < theCallStack.length)
            return theCallStack[depth].getFunctionName(); 
            return '????';      // ToDo: Should prolly raise an exception

        //FixMe: CodeMe:
        console.log('Aaaaaaaaaaaaargh!!!! ' + e);

and getCallingFunctionName() is called by logCallAndStartProfiling which is declared in a different file, utils.js, as exports.logCallAndStartProfiling = function(){ ... etc.

When I look at the result of getCallingFunctionName(), I see exports.logCallAndStartProfiling whereas I would prefer to see utils.logCallAndStartProfiling. Can I achieve this somehow by redeclaring the export, using a different syntax? Currently, I use var exports = (module.exports = {});.

Btw, for reasons that I won’t go into, TypeScript is not currently an option, although I will move to it later, but do not have, and cannot get, permission to do so just yet.


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Method 1

I am not sure if you will be able to do this easily.
I prepared a solution, but I am not sure if you will like it 😀

const { logCallAndStartProfiling } = require('./utils')
const utils = require('./other')

exports.logCallAndStartProfiling = function () {
  const functionName = utils.getCallingFunctionName(__filename)
const path = require('path')

function getStackTrace() {
  const orig = Error.prepareStackTrace
  Error.prepareStackTrace = function (_, theCallStack) {
    return theCallStack
  const err = new Error()
  Error.captureStackTrace(err, arguments.callee)
  const stack = err.stack
  Error.prepareStackTrace = orig
  return stack

exports.getCallingFunctionName = (fileName, depth = 1) => {
  try {
    const theCallStack = getStackTrace()

    if (depth >= theCallStack.length) return null

    const originalFunctionName = theCallStack[depth].getFunctionName()
    const functionName = originalFunctionName.split('exports.')[1]
    const baseFileName = path.basename(fileName).split('.js')[0]
    return `${baseFileName}.${functionName}`
  } catch (e) {
    return null

Export syntax in NodeJs

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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