Simple NodeJS script for batch renaming files using Regex

renamer.js

/**
 * Usage:
 * node renamer.js [files] "[regexMatcher]" "[regexReplace]"
 *
 * Example:
 * node rename.js *.mp3 "(.*)-([0-9].*)\.mp3" "%1.mp3"
 *
 * Extra tip: Add an alias to your .bash_profile that allows you to use `rename` anywhere.
 * alias rename="node PATH_TO_SCRIPT/renamer.js"
 */

console.log("\n-- Let's rename some stuff! --");
const fs = require("fs");
const readline = require("readline");

// SETUP VARS
const files = process.argv.slice(2, -2);
const regexMatch = new RegExp(process.argv.slice(-2).shift());
const regexReplace = process.argv.slice(-1).shift().replace(/%/, "$");

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout
});

const renameLog = [];

console.log("\n\n-- Rename example --");
files.forEach(current => {
  let newName = current.replace(regexMatch, regexReplace);
  console.log(`${current}\t\t->\t${newName}`);
  renameLog.push({current, newName});
});


rl.question("\n\n-- Want to rename the files like above? (y/n) ", function (answer) {
  if (answer === "y") {
    console.log("Renaming...");

    while (renameLog.length) {
      const change = renameLog.pop();
      fs.rename(change.current, change.newName, (err) => {
        if (err) { console.log("ERROR:", err); }

        if (renameLog.length === 0) {
          console.log("Done! Bye!");
          process.exit();
        }
      });
    }
  } else {
    console.log("Too bad...");
    process.exit();
  }
});

I found myself manually renaming a lot of files every once in a while and never found a tool that did the trick for me. I thought: "If I could just write some regex to do this simple stuff". So I made this script.

The example in the comment was used to strip of some numbers off some mp3 filenames. They we're named like track-1234678.mp3 and wanted to have them like track.mp3.

Let me you if this is any use to you!