node.js script to download cover art for the audio series "Die Drei Fragezeichen"

getDieDreiFragezeichenCovers.js

#!/usr/bin/node
/**
 * This script downloads audiobook covers for the "Die Drei Fragezeichen" audio-play series.
 * 
 * @example ```
 * node getDieDreiFragezeichenCovers.js
 * ```
 */

const fs = require('fs');
const path = require('path');
const https = require('https');

const MAX_EPISODE_NUMBER = 224;
const TARGET_FOLDER = './covers';

async function downloadFile(url, filename) {
	return new Promise((resolve, reject) => {
		fs.access(filename, fs.constants.F_OK, (err) => {
			if (err) {
				// file does not exist
				process.stdout.write(`Downloading "${filename}"...`);
				https.get(url, (res) => {
					if (res.statusCode !== 200) {
						console.log(`Status Code: ${res.statusCode}`)
						return reject();
					}
					const fileStream = fs.createWriteStream(filename);
					res.pipe(fileStream);
					fileStream.on("finish", () => {
						fileStream.close();
						console.log('Done')
						return resolve();
					});
				});
			} else {
				// file exists
				console.log(`File "${filename}" already exists`);
				resolve();
			}
		});
	});
}

async function getCover(number) {
	const numberFormatted = number.toString().padStart(3, "0");
	const url = `https://www.hoerspiel-paradies.de/images/cover/eur/ddf/hsp/4/${numberFormatted}.jpg`;
	const filename = `Die_Drei_Fragezeichen_${numberFormatted}.jpg`;
	const targetFile = path.join(TARGET_FOLDER, filename);
	await downloadFile(url, targetFile);
}

(async function () {
	// create target folder if it does not exist
	fs.mkdirSync(TARGET_FOLDER, { recursive: true });

	// download all covers
	const allEpisodes = Array.from({length: MAX_EPISODE_NUMBER}, (_, i) => i + 1);
	const errors = [];
	for await (const num of allEpisodes) {
		try {
			await getCover(num);
		} catch (error) {
			errors.push(num);
		}
	}

	// show errors if there are any
	if (errors.length > 0) {
		console.log(`Could not download covers for episodes: ${errors.join(', ')}`);
	} else {
		console.log('Done!');
	}
})();