ADP Payslip Downloader.js

// STEPS:

// Preferred Browser - Google Chrome Latest

// 1. Open ADP Paychecks Page. You will see the paychecks displayed with ID and date range.
// 2. Open Developer Tools by Mouse Right Click -> Inspect Element. Now, Select Console Tab (Usually Second Tab)
// 3. Paste the Below code and press Enter.
// 4. Once all the paychecks are downloaded to your Downloads Folder, goto next page of Paychecks and paste the code again in the Console.

function downloadURI(uri, name) {
    var link = document.createElement("a");
    link.download = name;
    link.href = uri;
    link.click();
}

(async () => {

    let arrayBufferToBase64 = (buffer) => {
        let binary = '';
        let bytes = [].slice.call(new Uint8Array(buffer));
        bytes.forEach((b) => binary += String.fromCharCode(b));
        return btoa(binary);
    };

    let downloadPDF = async (url) => {
        let req = await fetch(url);
        const buffer = await req.arrayBuffer();
        console.log(buffer);
        let base64Flag = `data:application/pdf;base64,`;
        let pdfStr = arrayBufferToBase64(buffer);
        return base64Flag + pdfStr;
    };

    let elements = document.querySelectorAll('[href^="viewpaycheck"]');
    elements = Array.prototype.slice.call(elements, 0);

    elements = elements.map((element) => {
        const columns = element.closest('tr').querySelectorAll('td');
        
        const name = `${columns[0].textContent}-${columns[2].textContent}`;
        return {
            name,
            url: element.getAttribute('href')
        }
    });

    for (const info of elements) {
        const resp = await downloadPDF(info.url);
        downloadURI(resp, info.name);
    }

    alert('All done in this page. Go to next records and run the script again');
})();