Installing Twisted

First things first: you need to get Twisted installed on your computer. Downloads and instructions for installing Twisted on various operating systems can be found at http://twistedmatrix.com/projects/core/. To enable additional functionality in Twisted, you'll have to install a couple of optional packages as well.

1.1.1. How Do I Do That?

Begin by downloading the latest Twisted release from http://www.twistedmatrix.com. Then install PyOpenSSL (a Python wrapper of the popular OpenSSL library), which Twisted uses to make encrypted Secure Socket Layer (SSL) connections. Finally, install PyCrypto , a package containing Python implementations of encryption algorithms used by the Secure SHell (SSH). Locations for these downloads are provided in each of the following platform-specific sections.

You don't need to install PyOpenSSL or PyCrypto in order to use Twisted. Without these packages installed, you won't be able to use Twisted's SSL and SSH features, but everything else will still work.

 

1.1.1.1. Windows

Go to http://twistedmatrix.com/projects/core/. Download the Twisted Windows "Sumo" installer for Python 2.4 (or your Python version). The Sumo binary includes the Twisted core, as well as a number of extra modules to support specific groups of protocols like mail and web. You'll need the full Sumo version of Twisted installed to run most of the examples in this book. Then go to http://twistedmatrix.com/products/download and find the section labeled "Twisted Dependencies for Windows." There you'll find links to installers for the latest versions of PyOpenSSL and PyCrypto.

It's possible that some of these packages might move to different pages as the Twisted web site grows and is restructured in the future. If one if these links doesn't work for you, try starting from the Twisted home page at http://twistedmatrix.com.

Once you've downloaded all three installers, run the Twisted Setup program. It's a simple installer, and it will automatically detect your existing Python installation. Next, run the PyOpenSSL and and PyCrypto installers. These are even simpler than the Twisted installer and take only a few seconds to complete.

When byte-compiling the Twisted modules, the Twisted Setup program will throw up a tiny, floating progress bar that sits in a very tiny window of its own. The unpacking may take several minutes.

Verify that the installation worked by importing the twisted package from an interactive Python prompt:

 $ python

 Python 2.3 (#1, Sep 13 2003, 00:49:11)

 Type "help", "copyright", "credits" or "license" for more information.

 >>> import twisted

 >>>

If the import twisted statement runs with no errors, you have a working Twisted install.

1.1.1.2. Mac OS X, Linux, and BSD

Many Linux distributions and BSD variants, including Debian, Ubuntu, Gentoo Linux, Red Hat Linux, and FreeBSD, have prepackaged versions of Twisted, PyOpenSSL, and PyCrypto available. Check the Twisted download page to see if it mentions your operating system, or search your favorite package repository. If there are packages available, make sure they are for Twisted 2.0 or higher, not the older 1.3 release.

If you can't find a prepackaged version of Twisted for your operating system or platform, refer to the following instructions on installing from source.