Puppeteer Auto Clien Screencapture App

clien.js

const puppeteer = require('puppeteer');

let prevNumber;

function again() {
    (async () => {
        const browser = await puppeteer.launch();
        const page = await browser.newPage();
        // Adjustments particular to this page to ensure we hit desktop breakpoint.
        page.setViewport({
            width: 1920,
            height: 100000,
            deviceScaleFactor: 1
        });

        if (prevNumber === undefined) {
            await page.goto('https://www.clien.net/service/group/community', {
                waitUntil: 'networkidle2'
            })
        } else {
            let data = await page.evaluate(() => {
                return {
                    postNumber: document.getElementsByClassName('list_item symph_row')[0].attributes[3].value
                };
            });
            if (prevNumber === data.postNumber) {
                console.log(`NO DATA Now in POST NUMBER : ${data.postNumber}`)
            } else {
                await page.goto(`https://www.clien.net/service/board/park/${data.postNumber}`, {
                    waitUntil: 'networkidle2'
                });

                prevNumber = data.postNumber + 1;

                /**
                 * Takes a screenshot of a DOM element on the page, with optional padding.
                 *
                 * @param {!{path:string, selector:string, padding:(number|undefined)}=} opts
                 * @return {!Promise<!Buffer>}
                 */
                async function screenshotDOMElement(opts = {}) {
                    const padding = 'padding' in opts ? opts.padding : 0;
                    const path = 'path' in opts ? opts.path : null;
                    const selector = opts.selector;

                    if (!selector)
                        throw Error('Please provide a selector.');

                    const rect = await page.evaluate(selector => {
                        const element = document.querySelector(selector);
                        if (!element)
                            return null;
                        const {
                            x,
                            y,
                            width,
                            height
                        } = element.getBoundingClientRect();
                        return {
                            left: x,
                            top: y,
                            width,
                            height,
                            id: element.id
                        };
                    }, selector);

                    if (!rect) {
                        console.log(`404 ERROR IN NUMBER : ${prevNumber-1}`)
                        throw Error(`Could not find element that matches selector: ${selector}.`);
                    }

                    return await page.screenshot({
                        path,
                        clip: {
                            x: rect.left - padding,
                            y: rect.top - 100 - padding,
                            width: rect.width + padding * 2,
                            height: rect.height + 100 + padding * 2
                        }
                    });
                }

                await screenshotDOMElement({
                    path: `./image/${data.postNumber}.png`,
                    selector: '.post_view',
                    padding: 5
                });
                // browser.close();
            }
        }
        browser.close();
    })();
}

setInterval(again, 5000)