You could install it yourself with pip:

$ pip install fedmsg_middleware

Or you could add fedmsg_middleware to the list of required packages in the setup.py file of your project.

Simply edit myapp/config/middleware.py and add the following to make_app(...):

# Wrap your base TurboGears 2 application with custom middleware here
import fedmsg_middleware
app = fedmsg_middleware.make_middleware(app)

Edit myapp/__init__.py and replace the return config.make_wsgi_app() line with the following:

import fedmsg_middleware
app = config.make_wsgi_app()
app = fedmsg_middleware.make_middleware(app)
return app

You can enable it in your PasteDeploy pipeline like so:

[pipeline:main]
pipeline =
    fedmsg_middleware
    my-app

[filter:fedmsg_middleware]
use = egg:fedmsg_middleware
topic = org.fedoraproject.prod.koji.*

[app:myapp]
...

The code and bug tracker live over at http://github.com/ralphbean/fedmsg_middleware. Please fork and improve!