A little over ten years ago, I started on a software project that was part hobby, part work-related. What it actually does isn’t relevant here. Instead, let’s talk about the components it has, and the tools to create it. It started out as a web page with some JavaScript code that loaded images and operated on them. Later, the JavaScript code invoked a Python CGI script on the web server it runs from to do some OpenCV image processing. So we have the following ingredients:

• HTML web page, for overall layout
• JavaScript files, loaded by the above web page
• Python code, invoked by the JavaScript as a CGI (Common Gateway Interface) script running on the server
• OpenCV, called by the Python code to do image processing
• Apache web server to serve the HTML/JavaScript/image files and run the Python scripts

Read on to learn about how I used Online IDEs and Docker for creating a portable web app.