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WSGI, GEvent and Web Sockets

Web Sockets is an emerging technology that enables bi-directional, full-duplex communications channels, over a single TCP socket. It was originally designed to be implemented in web browsers and web servers, but it can be used by any client or server application. Tests have demonstrated Web Sockets can provide a 500:1 reduction in network traffic and 3:1 reduction in latency. Web Sockets have been around in one form or another since 2009. However specifications are still not yet fully cooked. The W3C Web Applications Group is responsible for standardizing the WebSocket API. The editor of the W3C TR is Ian Hickson

Patching a GNOME Shell theme

Recently I wished to modify how Looking Glass, the GNOME Shell quasi-debugger and code inspector, was styled (or to use the GNOME Shell vernacular – themed.) I did not particularly like the green phosphorus foreground color and wished to change it to a more pleasing (at least to my eyes) white. I could have simply edited the default theme file, i.e. /usr/share/gnome-shell/theme/gnome-shell.css, but I would have lost such edits if the file was updated when an updated gnome-shell package was installed. Instead, I decided to see if I could write a GNOME Shell extension to achieve what I wanted to

Using an Extension to Monkey Patch the GNOME Shell

Wikipedia defines a monkey patch as a way to extend or modify the run-time code of dynamic languages without altering the original source code. JavaScript is one such dynamic language. The GNOME Shell UI is written in JavaScript so monkey patching of the GNOME Shell is possible. Some time ago, I figured out why the Search Provider buttons in the Activities Overview screen did not display search providers icons. See here. I raised a new low priority bug report in GNOME bugzilla but recently decided to see if I could write a GNOME Shell extension which used monkey patching to

GNOME Shell Weather Extension

The current version of the GNOME shell does not come with a built-in weather application. As a result I, and at least two other developers that I am aware of, have written GNOME Shell extensions to provide this functionality. In this post, I show you how to write a simple weather extension for the GNOME Shell using the free weather data from World Weather Online (WWO). What is different about this particular weather extension is that it displays 5 days’ worth of forecast data and uses the weather data suppliers’ images instead of GNOME icons to display a pictorial representation

More GNOME Shell Customization

If you plan to customize the GNOME Shell in any meaningful way, you need to understand the technologies underlying the GNOME Shell and understand how to write a GNOME Shell extension to provide the customization that you require. In this post I delve deeper into the technologies behind the new GNOME Shell and provide sample code for a number of simple extensions which demonstrate how to customize and extend various components of the GNOME Shell user interface. Essentially, the GNOME Shell is an integrated window manager, compositor, and application launcher. It acts as a composting window manager for the desktop