Headless Browsers

The library, eschewing unstable and nascent ECMAScript features, plays nicely with most headless browsers. This demo shows a few common headless scenarios.

NodeJS does not ship with its own layout engine. For advanced HTML exports, a headless browser is generally indistinguishable from a browser process.

Chromium Automation with Puppeteer

Puppeteer enables headless Chromium automation.

html.js shows a dedicated script for converting an HTML file to XLSB using puppeteer. The first argument is the path to the HTML file. The script writes to output.xlsb:

# read from test.html and write to output.xlsb
$ node html.js test.html

The script pulls up the webpage using headless Chromium and adds a script tag reference to the standalone browser build. That will make the XLSX variable available to future scripts added in the page! The browser context is not able to save the file using writeFile, so the demo generates the XLSB spreadsheet bytes with the base64 type, sends the string back to the main process, and uses fs.writeFileSync to write the file.

WebKit Automation with PhantomJS

This was tested using PhantomJS 2.1.1

$ phantomjs phantomjs.js

The flow is similar to the Puppeteer flow (scrape table and generate workbook in website context, copy string back, write string to file from main process).

The binary type generates strings that can be written in PhantomJS using the fs.write method with mode "wb".

wkhtmltopdf

This was tested in wkhtmltopdf 0.12.4, installed using the official binaries:

$ wkhtmltopdf --javascript-delay 20000 http://oss.sheetjs.com/sheetjs/tests/ test.pdf