printTextForGivenElement.js

printTextForGivenElement.js

const fs = require('fs');
const cheerio = require('cheerio');
const puppeteer = require('puppeteer');
let app = {};

app.parse = async function(data, elementSelector) {
	if (data.length === 0) {
		console.log("No data!");
		return;
	}
	
	const $ = cheerio.load(data);

	const elements = $(elementSelector);
	elements.each(function(_, elem) {
		const text = $(this).text();

		if (text.length > 0) {
			console.log(text);
		} else {
			console.log($.html(this));
		}
	});
};

app.getDataFromURL = async function getPage(link) {
	const device = puppeteer.devices['iPad Pro landscape'];
	const browser = await puppeteer.launch({args: ['--no-sandbox']});
	const page = await browser.newPage();
	await page.emulate(device);

	await page.goto(link, {waitUntil: 'networkidle2'});
	const content = await page.content();
	await browser.close();

	return content;
};


app.getDataFromFile = function(file, elementSelector) {
	fs.readFile(file, "utf8", function read(err, data) {
		if (err) {
			throw err;
		}

		app.parse(data, elementSelector);
	});
};

app.usage = function() {
	console.log(`You must specify path to the file and element selector!
Possible selectors:
<element_name>
.<class_name>
#<id_name>`);
};

app.main = async function() {
	if (process.argv.length < 4) {
		app.usage();
		return;
	}

	const path = process.argv[2];
	const elementSelector = process.argv[3];

	if (fs.existsSync(path)) {
		app.getDataFromFile(path, elementSelector);
	} else {
		const data = await app.getDataFromURL(path);
		app.parse(data, elementSelector);
	}
};

app.main();