FAQ

Fabric is best installed via pip (highly recommended) or easy_install (older, but still works fine), e.g.:

$ pip install fabric

You may also opt to use your operating system’s package manager; the package is typically called fabric or python-fabric. E.g.:

$ sudo apt-get install fabric

Advanced users wanting to install a development version may use pip to grab the latest master branch (as well as the dev version of the Paramiko dependency):

$ pip install -e git+https://github.com/paramiko/paramiko/#egg=paramiko
$ pip install -e git+https://github.com/fabric/fabric/#egg=fabric

Warning

Development installs of Fabric, regardless of whether they involve source checkouts or direct pip installs, require the development version of Paramiko to be installed beforehand or Fabric’s installation may fail.

Dependencies

In order for Fabric’s installation to succeed, you will need three primary pieces of software:

  • the Python programming language;
  • the setuptools packaging/installation library;
  • and the Python Paramiko SSH library. Paramiko’s dependencies differ significantly between the 1.x and 2.x releases. See the Paramiko installation docs for more info.

and, if using the parallel execution mode:

If you’re using Paramiko 1.12 or above, you will also need an additional dependency for Paramiko:

Please read on for important details on these – there are a few gotchas.

Python

Fabric requires Python version 2.5 - 2.7. Some caveats and notes about other Python versions:

  • We are not planning on supporting Python 2.4 given its age and the number of useful tools in Python 2.5 such as context managers and new modules. That said, the actual amount of 2.5-specific functionality is not prohibitively large, and we would link to – but not support – a third-party 2.4-compatible fork. (No such fork exists at this time, to our knowledge.)
  • Fabric has not yet been tested on Python 3.x and is thus likely to be incompatible with that line of development. However, we try to be at least somewhat forward-looking (e.g. using print() instead of print) and will definitely be porting to 3.x in the future once our dependencies do.

setuptools

Setuptools comes with some Python installations by default; if yours doesn’t, you’ll need to grab it. In such situations it’s typically packaged as python-setuptools, py25-setuptools or similar. Fabric may drop its setuptools dependency in the future, or include alternative support for the Distribute project, but for now setuptools is required for installation.

multiprocessing

An optional dependency, the multiprocessing library is included in Python’s standard library in version 2.6 and higher. If you’re using Python 2.5 and want to make use of Fabric’s parallel execution features you’ll need to install it manually; the recommended route, as usual, is via pip. Please see the multiprocessing PyPI page for details.

Warning

Early versions of Python 2.6 (in our testing, 2.6.0 through 2.6.2) ship with a buggy multiprocessing module that appears to cause Fabric to hang at the end of sessions involving large numbers of concurrent hosts. If you encounter this problem, either use env.pool_size / -z to limit the amount of concurrency, or upgrade to Python >=2.6.3.

Python 2.5 is unaffected, as it requires the PyPI version of multiprocessing, which is newer than that shipped with Python <2.6.3.

Development dependencies

If you are interested in doing development work on Fabric (or even just running the test suite), you may also need to install some or all of the following packages:

For an up-to-date list of exact testing/development requirements, including version numbers, please see the requirements.txt file included with the source distribution. This file is intended to be used with pip, e.g. pip install -r requirements.txt.

Downloads

To obtain a tar.gz or zip archive of the Fabric source code, you may visit Fabric’s PyPI page, which offers manual downloads in addition to being the entry point for pip and easy-install.

Source code checkouts

The Fabric developers manage the project’s source code with the Git DVCS. To follow Fabric’s development via Git instead of downloading official releases, you have the following options:

Note

If you’ve obtained the Fabric source via source control and plan on updating your checkout in the future, we highly suggest using python setup.py develop instead – it will use symbolic links instead of file copies, ensuring that imports of the library or use of the command-line tool will always refer to your checkout.

For information on the hows and whys of Fabric development, including which branches may be of interest and how you can help out, please see the Development page.

ActivePython and PyPM

Windows users who already have ActiveState’s ActivePython distribution installed may find Fabric is best installed with its package manager, PyPM. Below is example output from an installation of Fabric via pypm:

C:\> pypm install fabric
The following packages will be installed into "%APPDATA%\Python" (2.7):
 paramiko-1.7.8 pycrypto-2.4 fabric-1.3.0
Get: [pypm-free.activestate.com] fabric 1.3.0
Get: [pypm-free.activestate.com] paramiko 1.7.8
Get: [pypm-free.activestate.com] pycrypto 2.4
Installing paramiko-1.7.8
Installing pycrypto-2.4
Installing fabric-1.3.0
Fixing script %APPDATA%\Python\Scripts\fab-script.py
C:\>