How to read GNOME shell extension source code?

by yaobin.wen

These days I tried to study the source code of the GNOME shell extension micheleg/dash-to-dock. However, I found the source code was not that easy to understand if you don’t know WHERE to find the relevant source code.

Firstly, the GNOME Wiki page for the shell extension provides an overview for GNOME shell extensions. Specifically, read the Creating Extensions page which tells you that the two essential files for an extension are extension.js and metadata.json. Therefore, when you start to read the source code of a GNOME shell extension, start with these two files.

In the source code, you will find a lot of imports. Take the appIcons.js of v0.9.1 for example:

const Clutter = imports.gi.Clutter;
const GdkPixbuf = imports.gi.GdkPixbuf
const Gio = imports.gi.Gio;
const GLib = imports.gi.GLib;
const Gtk = imports.gi.Gtk;
const Signals = imports.signals;
const Lang = imports.lang;
const Meta = imports.gi.Meta;
const Shell = imports.gi.Shell;
const St = imports.gi.St;
const Mainloop = imports.mainloop;

These imports fall into two major categories:

• Imported from imports.gi.
• Imported from imports directly.

The documentation for the first category can be found here: gjs API references. Note that you must enable the document before you can open and read it. For example:

The documentation for the second category can be found in the source code of gjs. More specifically, in modules/script, modules/core, and modules/core/overrides. For example,