You will need Python version 2.4 or better to run repoze.bfg.
repoze.bfg is known to run on all popular Unix-like systems such as Linux, MacOS X, and FreeBSD as well as on Windows platforms. It is also known to run on Google’s App Engine and Jython.
repoze.bfg installation does not require the compilation of any C code, so you need only a Python interpreter that meets the requirements mentioned.
If your system doesn’t have a Python interpreter, and you’re on UNIX, you can either install Python using your operating system’s package manager or you can install Python from source fairly easily on any UNIX system that has development tools.
You can use your system’s “package manager” to install Python. Every system’s package manager is slightly different, but the “flavor” of them is usually the same.
For example, on an Ubuntu Linux system, to use the system package manager to install a Python 2.6 interpreter, use the following command:
$ sudo apt-get install python2.6-dev
Once these steps are performed, the Python interpreter will usually be invokable via python2.6 from a shell prompt.
It’s useful to use a Python interpreter that isn’t the “system” Python interpreter to develop your software. The authors of repoze.bfg tend not to use the system Python for development purposes; always a self-compiled one. Compiling Python is usually easy, and often the “system” Python is compiled with options that aren’t optimal for web development.
To compile software on your UNIX system, typically you need development tools. Often these can be installed via the package manager. For example, this works to do so on an Ubuntu Linux system:
$ sudo apt-get install build-essential
On Mac OS X, installing XCode has much the same effect.
Once you’ve got development tools installed on your system, On the same system, to install a Python 2.6 interpreter from source, use the following commands:
[chrism@vitaminf ~]$ cd ~ [chrism@vitaminf ~]$ mkdir tmp [chrism@vitaminf ~]$ mkdir opt [chrism@vitaminf ~]$ cd tmp [chrism@vitaminf tmp]$ cd tmp [chrism@vitaminf tmp]$ wget \ http://www.python.org/ftp/python/2.6.4/Python-2.6.4.tgz [chrism@vitaminf tmp]$ tar xvzf Python-2.6.4.tgz [chrism@vitaminf tmp]$ cd Python-2.6.4 [chrism@vitaminf Python-2.6.4]$ ./configure \ --prefix=$HOME/opt/Python-2.6.4 [chrism@vitaminf Python-2.6.4]$ make; make install
Once these steps are performed, the Python interpreter will be invokable via $HOME/opt/Python-2.6.4/bin/python from a shell prompt.
If your Windows system doesn’t have a Python interpreter, you’ll need to install it by downloading a Python 2.6-series interpreter executable from python.org’s download section (the files labeled “Windows Installer”). Once you’ve downloaded it, double click on the executable and accept the defaults during the installation process. You may also need to download and install the Python for Windows extensions.
After you install Python on Windows, you may need to add the C:\Python26 directory to your environment’s Path in order to make it possible to invoke Python from a command prompt by typing python. To do so, right click My Computer, select Properties –> Advanced Tab –> Environment Variables and add that directory to the end of the Path environment variable.
It is best practice to install repoze.bfg into a “virtual” Python environment in order to obtain isolation from any “system” packages you’ve got installed in your Python version. This can be done by using the virtualenv package. Using a virtualenv will also prevent repoze.bfg from globally installing versions of packages that are not compatible with your system Python.
To set up a virtualenv in which to install repoze.bfg, first ensure that setuptools is installed. Invoke import setuptools within the Python interpreter you’d like to run repoze.bfg under:
[chrism@vitaminf bfg]$ python Python 2.4.5 (#1, Aug 29 2008, 12:27:37) [GCC 4.0.1 (Apple Inc. build 5465)] on darwin Type "help", "copyright", "credits" or "license" for more information. >>> import setuptools
If running import setuptools does not raise an ImportError, it means that setuptools is already installed into your Python interpreter. If import setuptools fails, you will need to install setuptools manually. Note that above we’re using a Python 2.4-series interpreter on Mac OS X; your output may differ if you’re using a later Python version or a different platform.
If you are using a “system” Python (one installed by your OS distributor or a 3rd-party packager such as Fink or MacPorts), you can usually install the setuptools package by using your system’s package manager. If you cannot do this, or if you’re using a self-installed version of Python, you will need to install setuptools “by hand”. Installing setuptools “by hand” is always a reasonable thing to do, even if your package manager already has a pre-chewed version of setuptools for installation.
To install setuptools by hand, first download ez_setup.py then invoke it using the Python interpreter into which you want to install setuptools.
$ python ez_setup.py
Once this command is invoked, setuptools should be installed on your system. If the command fails due to permission errors, you may need to be the administrative user on your system to successfully invoke the script. To remediate this, you may need to do:
$ sudo python ez_setup.py
$ easy_install virtualenv
This command should succeed, and tell you that the virtualenv package is now installed. If it fails due to permission errors, you may need to install it as your system’s administrative user. For example:
$ sudo easy_install virtualenv
Once the virtualenv package is installed in your Python, you can then create a virtual environment. To do so, invoke the following:
$ virtualenv --no-site-packages bfgenv New python executable in bfgenv/bin/python Installing setuptools.............done.
Using --no-site-packages when generating your virtualenv is very important. This flag provides the necessary isolation for running the set of packages required by repoze.bfg. If you do not specify --no-site-packages, it’s possible that repoze.bfg will not install properly into the virtualenv, or, even if it does, may not run properly, depending on the packages you’ve already got installed into your Python’s “main” site-packages dir.
If you’re on UNIX, do not use sudo to run the virtualenv script. It’s perfectly acceptable (and desirable) to create a virtualenv as a normal user.
You should perform any following commands that mention a “bin” directory from within the bfgenv virtualenv dir.
After you’ve got your bfgenv virtualenv installed, you may install repoze.bfg itself using the following commands from within the virtualenv (bfgenv) directory:
$ bin/easy_install -i http://dist.repoze.org/bfg/current/simple \ repoze.bfg
This command will take longer than the previous ones to complete, as it downloads and installs a number of dependencies.
Install, or find Python 2.6 for your system.
Install the Python for Windows extensions. Make sure to pick the right download for Python 2.6 and install it using the same Python installation from the previous step.
Install latest setuptools distribution into the Python you obtained/installed/found in the step above: download ez_setup.py and run it using the python interpreter of your Python 2.6 installation using a command prompt:
c:\> c:\Python26\python ez_setup.py
Use that Python’s bin/easy_install to install virtualenv:
c:\> c:\Python26\Scripts\easy_install virtualenv
Use that Python’s virtualenv to make a workspace:
c:\> c:\Python26\Scripts\virtualenv --no-site-packages bfgenv
Switch to the bfgenv directory:
c:\> cd bfgenv
(Optional) Consider using bin\activate.bat to make your shell environment wired to use the virtualenv.
Use easy_install pointed at the “current” index to get repoze.bfg and its direct dependencies installed:
c:\bfgenv> Scripts\easy_install -i \ http://dist.repoze.org/bfg/current/simple repoze.bfg
Running repoze.bfg on Google’s App Engine documents the steps required to install a repoze.bfg application on Google App Engine.
repoze.bfg is known to work under Jython version 2.5.1. Install Jython, and then follow the installation steps for repoze.bfg on your platform described in one of the sections entitled Installing repoze.bfg on a UNIX System or Installing repoze.bfg on a Windows System above, replacing the python command with jython as necessary. The steps are exactly the same except you should use the jython command name instead of the python command name.
One caveat exists to using repoze.bfg under Jython: the Chameleon templating engine, which is the default templating engine for repoze.bfg does not work on Jython.
The repoze.bfg.jinja2 distribution provides templating for repoze.bfg using the Jinja2 templating system. You may install it like so using the easy_install command for Jython:
$ easy_install repoze.bfg.jinja2
Once this is done, you can use this command to get started with a repoze.bfg sample application that uses the Jinja2 templating engine:
$ paster create -t bfg_jinja2_starter
See the chapter entitled Creating a repoze.bfg Project for more information about the paster create command.
When you easy_install repoze.bfg, various Zope libraries, various Chameleon libraries, WebOb, Paste, PasteScript, and PasteDeploy libraries are installed.
Additionally, as chronicled in Creating a repoze.bfg Project, PasteScript (aka paster) templates will be registered that make it easy to start a new repoze.bfg project.