Obtaining and Installing Comet

Installation using pip

The latest version of Comet and all of the tools it depends upon can be installed using pip. It is generally a good idea to use virtualenv to create an isolated, self-contained installation:

$ virtualenv comet
$ . comet/bin/activate
$ pip install comet

Manual installation


Comet is developed targeting Python 2.7 with experimental support for Python 3.4 and later. It depends upon:

  • Twisted (version 11.1.0 or later for Python 2.7; 16.0 or later for Python 3.x);
  • lxml (version 2.3 or later);
  • zope.interface (versions 3.6.0 or later for Python 2.6; 4.1.1 or later for Python 3.x);
  • py2-ipaddress (Python 2.7 only; not required for Python 3.x).

How you make these dependencies available on your system is up to your (or, perhaps, to your system administrator). However, the author strongly suggests you might start by taking a look at virtualenv.


See the release history to obtain the latest version of Comet or check out the source from the GitHub repository. The latest version of the source can be obtained using git:

$ git clone https://github.com/jdswinbank/Comet.git


Comet includes a distutils setup script which can be used for installation. To install in your system-default location, run:

$ python setup.py install

A number of other options are available: see also:

$ python setup.py --help


After installation, you should check that Comet is working properly. The Twisted framework used by Comet makes this easy with its trial tool. Simply run:

$ trial comet

No failures or errors are expected in the test suite. If you see a problem, please contact the author for help.