Creating a GenGIS plugin

From The GenGIS wiki
Revision as of 00:16, 4 March 2012 by Dparks (Talk | contribs)

Jump to: navigation, search

The functionality of GenGIS can be extended by writing a Python plugin. Python plugins reside in the plugins folder within your GenGIS directory. In this tutorial we will create a simple "Hello World" plugin which writes a simple greeting to the GenGIS viewport.

Specifying Plugin Details

Begin by creating the directory HelloWorld within the GenGIS plugins' directory. Within this directory create a file called This file contains general information about your plugin which is used by GenGIS. For our Hello World plugin, enter the following into

  def name():
    return "Hello World"
  def version():
    return "Version 1.0"

  def description():
    return "Prints Hello World to the Viewport."
  def authors():
    return "Donovan Parks"

  def publicationDate():
    return "March 1, 2012"
  def minimumVersionOfGenGIS(): 
    return "2.0"

  def requireR():
    return False

All plugins require an file and must contain all the functions shown above.

Writing the Plugin

The plugin must contain a Python file with the same name as the directory in which it resides. In this example, we need to have a file called and this file must contain a class called HelloWorld. Within GenGIS an object of this class is created whenever a user invokes the plugin. A plugin interacts with GenGIS through an API which is exposed through a module called GenGIS. Create the file with the following code:

Further information about the GenGIS API can be found in the GenGIS manual and any of the existing plugins examined in order to see how they function.

Releasing a Plugin

We encourage you to make your plugins available to other GenGIS users. If you wish to have your plugin made available on the GenGIS website please contact Rob Beiko (