You will need Python version 2.4 or better to run repoze.bfg. It has been tested under Python 2.4.5, Python 2.5.2 and Python 2.6. Development of repoze.bfg is currently done primarily under Python 2.4 and Python 2.5. repoze.bfg does not run under any version of Python before 2.4, and does not run under Python 3.X.
You will need setuptools installed on within your Python system in order to run the easy_install command.
Installation of repoze.bfg does not require the compilation of any C code, so as long as you have a Python interpreter that meets the above requirements, you do not need to have development tools installed on the target machine to install repoze.bfg.
BFG is known to run properly on all popular Unix-like systems such as Linux, MacOS X, and FreeBSD.
repoze.bfg does run on Windows systems. However, none of its developers use Windows as a primary development platform. Therefore, most of the platform-specific documentation (excepting this chapter) assumes you’re using a UNIX system. If you’re using a Windows system, you’ll need to transliterate command lines in the documentation to their Windows equivalents.
repoze.bfg is also known to run on Google’s App Engine.
It is not known whether repoze.bfg will or will not run under Jython or IronPython.
If you’d like to help make sure repoze.bfg keeps running on your favorite alternate platform, we’d love to hear from you. Please contact us via the repoze.dev maillist if you’d like to contribute.
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 2.5 interpreter, use the following command:
$ sudo apt-get install python2.5-dev
Once these steps are performed, the Python interpreter will usually be invokable via python2.5 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 never use the system Python for development purposes; always a self-compiled one. Compiling Python is 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 2.5 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://python.org/ftp/python/2.5.4/Python-2.5.4.tgz [chrism@vitaminf tmp]$ tar xvzf Python-2.5.4.tgz [chrism@vitaminf tmp]$ cd Python-2.5.4 [chrism@vitaminf Python-2.5.4]$ ./configure --prefix=$HOME/opt/Python-2.5.4 [chrism@vitaminf Python-2.5.4]$ make; make install
Once these steps are performed, the Python interpreter will be invokable via $HOME/opt/Python-2.5.4/bin/python from a shell prompt.
If your Windows system doesn’t have a Python interpreter, you’ll need to install it by downloading a Python 2.4, 2.5 or 2.6-series interpreter executable from python.org’s download section (the files labeled “Windows Installer”). Once you’ve downloaded it, double click on the executable and accept the defaults during the installation process. You may also need to download and install the Python for Windows extensions.
It is advisable to install repoze.bfg into a virtualenv in order to obtain isolation from any “system” packages you’ve got installed in your Python version (and likewise, to prevent repoze.bfg from globally installing versions of packages that are not compatible with your system Python).
To set up a virtualenv to install repoze.bfg within, first ensure that setuptools is installed. Invoke import setuptools within the Python interpreter you’d like to run repoze.bfg under:
[chrism@vitaminf bfg]$ 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 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.
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 a setuptools package 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 you want to install setuptools into.
$ sudo 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 actually create a virtual environment. To do so, invoke the following:
1 2 3
$ 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/1.1/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 2.5 for your system.
Install the Python for Windows extensions. Make sure to pick the right download for Python 2.5 and install it using the same Python installation from the previous step.
Install latest setuptools 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 2.5 installation using a command prompt:
c:\> c:\Python25\python ez_setup.py
Use that Python’s bin/easy_install to install virtualenv:
c:\> c:\Python25\Scripts\easy_install virtualenv
Use that Python’s virtualenv to make a workspace:
c:\> c:\Python25\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 and point to the BFG “1.1” index to get BFG and its direct dependencies installed:
c:\bfgenv> Scripts\easy_install -i http://dist.repoze.org/bfg/1.1/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.
When you easy_install repoze.bfg, various Zope libraries, various Chameleon libraries, WebOb, Paste, PasteScript, and PasteDeploy libraries are installed.
Additionally, as shown in the next section, PasteScript (aka paster) templates will be registered that make it easy to start a new repoze.bfg project.