Convert M/D/YYYY format to YYYY-MM-DD in all markdown files in current folder

convert-date-in-md.js

#!/usr/bin/env node
"use strict";

/* Convert date formats in markdown
 *
 * This script converts a "(M/D/YYYY)" date format to "(YYYY-MM-DD)" in *all*
 * markdown files within the folder it is placed
 * Use `node convert-date-in-md.js` to execute
*/
const fs = require("fs");
const regex = /(\(\d+\/\d+\/\d+\))/g;

function padZero(number) {
  return ("0" + number).slice(-2);
}

// Convert (M/D/YYYY) to (YYYY-MM-DD)
function convertDates(string) {
  return string.replace(regex, date => {
    const [, m, d, y] = date.split(/[(/)]/);
    return `(${y}-${padZero(m)}-${padZero(d)})`;
  })
}

function processMarkdownInFolder() {
  return new Promise((resolve, reject) => {
    const path = "./";
    fs.readdir(path, (err, files) => {
      if (err) {
        console.log("Error reading the current folder", err);
        reject(err);
      }
      return Promise.all(files.map(file => {
        if (file.endsWith(".md")) {
          readFile(path + file).then(content => writeFile(file, convertDates(content)));
        }
        Promise.resolve();
      }))
      .then(resolve)
      .catch(exit);
    });
  });
}

function readFile(name) {
  return new Promise((resolve, reject) => {
    fs.readFile(name, "utf8", (err, file) => {
      if (err) {
        return reject(err);
      }
      resolve(file);
    });
  });
}

function writeFile(name, obj) {
  return new Promise((resolve, reject) => {
    fs.writeFile(name, obj, "utf8", err => {
      if (err) {
        console.log(`Error writing ${name}`, err);
        return reject(err);
      }
      resolve();
    });
  });
}

function exit(err) {
  if (err) console.error(err);
  process.exit(err ? 1 : 0);
}

processMarkdownInFolder().then(() => console.log("\x1b[32m%s\x1b[0m", "Date conversion complete"));

The script was used for this wiki page conversion.