x2go package

Module contents

Python X2Go is a Python module that implements X2Go client support for the free X2Go Server project (http://wiki.x2go.org) in Python.

Introduction

With Python X2Go you can write your own X2Go clients or embed X2Go client features into already existing application environments.

NOTE: Beginning with v0.4.0.0 of Python X2Go all class names start with X2Go***. Earlier versions used X2go***. As X2Go is the official name of the project (i.e. with a capital X and a capital G) we have adapted the class names to this circumstance.

API Concept

Python X2Go consists of quite a few classes. Furthermore, Python X2Go is quite heavily taking advantage of Python’s threading features. When providing a library like Python X2Go, it is always quite a task to keep the library code compatible with former versions of the same library. This is intended for Python X2Go, but with some restraints.

Python X2Go only offers five public API classes. With the release of version 0.1.0.0, we will try to keep these five public API classes of future releases as compatible as possible with versions of Python X2Go greater/equal than v0.1.0.0.

The five public API classes are:

Plus two extra classes on MS Windows platforms:

Any other of the Python X2Go classes may be subject to internal changes and the way of addressing these classes in code may vary between different versions of Python X2Go. If you directly use other than the five public API classes in your own applications, so please be warned.

API Structure

When using Python X2Go in your applications, the basic idea is that you create your own class and inherit the X2GoClient class in that:

import x2go
class MyX2GoClient(x2go.X2GoClient):

    ...

Python X2Go is capable of handling multiple running/suspended sessions within the same client instance, so for your application, there should not be any need of instantiating more than one x2go.client.X2GoClient object in parallel.

NOTE: Doing so is–herewith–fully disrecommended.

The x2go.client.X2GoClient class flattens the complex structure of Python X2Go into many x2go.client.X2GoClient methods that you can use in your own MyX2GoClient instance.

However, it might be handy to retrieve a whole X2Go session instance from the x2go.client.X2GoClient instance. This can be achieved by the L{X2GoClient.register_session()} method:

import x2go
my_x2gocli = MyX2GoClient()
reg_session_instance = my_x2gocli.register_session(<options>, return_object=True)

Whereas <options> can be as simple as:

»profile_name=<PROFILE_NAME_IN_SESSIONS_FILE>«

or contain a whole set of x2go.session.X2GoSession parameters that can be used to start a session manually (i.e. a session that is based on a pre-configured session profile in either of the »sessions« config files).

The L{X2GoClient.register_session()} method—in object-retrieval-mode—returns an x2go.session.X2GoSession instance. With this instance you can then manage your X2Go session:

import gevent, getpass
pw=getpass.getpass()
# authenticate
reg_session_instance.connect(password=pw, <further_options>)
# then launch the session window with either a new session
if start:
    reg_session_instance.start()
# or resume a session
if resume:
    reg_session_instance.resume(session_name=<X2Go-session-name>)
# leave it runnint for 60 seconds
gevent.sleep(60)
# and then suspend
if suspend:
    reg_session_instance.suspend()
# or alternatively terminate it
elif terminate:
    reg_session_instance.terminate()

How to access—especially how to modify—the X2Go client configuration files »settings«, »printing«, »sessions« and »xconfig« (Windows only) is explained in detail with each class declaration in this API documentation. Please refer to the class docs of x2go.backends.settings.base.X2GoClientSettings, x2go.backends.printing.base.X2GoClientPrinting, x2go.backends.profiles.base.X2GoSessionProfiles and x2go.xserver.X2GoXServer.

Configuration and Session Management

Python X2Go strictly separates configuration management from session management. The classes needed for session management / administration are supposed to only gain »read access« to the classes handling the X2Go client configuration nodes.

A configuration node in Python X2Go can be a file, a gconf database section, a section in the Windows registry, etc.

NOTE: Each configuration node will be re-read whenever it is needed by an X2Go sesion or the X2GoClient class itself.

Conclusively, any change to either of the configuration nodes will be reflected as a change in your X2Go client behaviour:

  • x2go.backends.profiles.base.X2GoSessionProfiles: changes to a session profile in the »sessions« node will be available for the next registered x2go.session.X2GoSession instance
  • x2go.backends.printing.base.X2GoClientPrinting: on each incoming X2Go print job the »printing« configuration node will be re-read, thus you can change your X2Go client’s print setup during a running session
  • x2go.backends.settings.base.X2GoClientSettings: also the configuration node »settings« is re-read whenever needed in the course of X2Go session management
  • x2go.xserver.X2GoClientXConfig and x2go.xserver.X2GoXServer (Windows only): these classes will only be initialized once (starting the XServer on Windows platforms) on construction of an x2go.client.X2GoClient instance

Dependencies

Python X2Go takes advantage of the libevent/greenlet implementation gevent (http://www.gevent.org). The least needed version of Python gevent is 0.13.0. On MS Windows Python gevent 1.0 is highly recommended.

Python X2Go (because of gevent) requires at least Python 2.6 or Python 3.4. Further recent information on Python X2Go is available at: https://wiki.x2go.org/doku.php/wiki:libs:python-x2go

Contact

If you have any questions concerning Python X2Go, please sign up for the x2go-dev list (https://lists.x2go.org/listinfo/x2go-dev) and post your questions, requests and feedbacks there.