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How to setup Raspbian Jessie Lite on Raspberry Pi 3 to run Python 3 applications

The Raspbian operating system is the Raspberry Pi Foundation's official supported operating system. As of this writing, Raspbian comes in two flavours - one with a graphical user interface for us to build a low cost desktop computer and the other without the graphical user interface.

If you intend to use your Raspberry Pi 3 with sensors and build a web interface for you to manage those sensors, Raspbian Jessie Lite is one operating system which you may want to install on your Raspberry Pi 3.

And with the versatility of Python 3, setting up Raspbian Jessie Lite on Raspberry Pi 3 to run Python 3 applications will be one of the first task that you will perform before you embark on your next sensor based project with the Raspberry Pi 3.

This post documents the steps that I took to setup Raspbian Jessie Lite on Raspberry Pi 3 to run Python 3 applications.

How to host your Python 3 Flask MVP with Supervisor on Ubuntu Server 16.04

Due to its minimalistic design, the Python Flask framework is ideal for building the web server layer of minimal viable products (MVP) to validate customers' needs. However, development work is just one part of the user validation efforts. To ensure that our customer can access our Flask MVP and provide feedback as and when they are available, we will need to get it running with as a server daemon.

Supervisor is a convenient tool for running applications as a server daemon.

This post documents the steps that I took to host a Python 3 Flask MVP with Supervisor on an Ubuntu Server 16.04 instance.

How to setup Ubuntu Classic Server 16.04 on Raspberry Pi 3 for running Python 3 applications

Most of the customers who wanted to try out my minimal viable products (MVP) would provide me with an instance of Ubuntu Classic Server 16.0x these days. As such, it makes sense for me to trial my MVPs on the Ubuntu Classic Server 16.0x to ensure that I spend minimal time in deploying my MVPs to validate my customers' needs. Since I have a few Raspberry Pi 3s lying around in the house, I can install a version of Ubuntu Classic Server 16.0x to serve as the development server for me to trial my MVPs.

Fortunately, the good folks at ubuntu-pi-flavour-maker.org had put up an optimised Ubuntu Classic Server 16.04 image for Raspberry Pi 3.

This post documents the steps that I took to run Ubuntu Classic Server 16.04 on my Raspberry Pi 3 for running Python 3 applications.

Proving that we can use jQuery to push a dynamically generated file to the web browser based on the user's input

In order to demonstrate the possibility of using JavaScript/jQuery to push a dynamically generated file from the server backend to the browser, a sample scenario was created.

There is a number dial that changes rapidly and a text field for the user to enter his name. When the user clicks on the "get lucky number" button, jQuery is used to send the lucky number on the number dial and the user name to the server.

The server generates a text file based on the input from the user and sends the file back to the browser. The browser will then show a download dialog box for the user to decide whether to save a copy of the file or view the file using one of the native applications found in his/her computer.

Using jQuery to detect user checking and unchecking a checkbox

Demonstration of using jQuery to detect user checking and unchecking of a HTML checkbox.

Message will be hidden when the user checks the HTML checkbox and shown when the user unchecks the HTML checkbox.

Using jQuery to access the DOM structure of parent HTML webpage from within the child HTML window

This is a demonstration of how a child web page can access the DOM structure of its parent web page using jQuery and JavaScript.

It shows a button on the parent web page to spawn the child web page in a separate browser window.

The child web page provides a text field and a submit button to write user's input to the parent web page.