Hi Greg, > I'm not familiar with Python packaging, can you talk about this a bit more? I'd be happy to. PyPI (the Python Package Index) is a repo on python.org for distributing/sharing Python projects. People can publish their code onto it for others to download. If you are a Perl guy, it's a similar concept to CPAN. Since Python is an interpreted language, it is fairly trivial to distribute code in a portable way. Obviously there are complications and exceptions to everything, but I believe this is true more often than not. Python has a few different tools available for installing modules -- easy_install and pip come to mind. Both of these are essentially their own package managers, solving dependencies and such. One can do things like "easy_install matplotlib" or "easy_install python-mysql" and this package will be searched for on PyPI (and other repos) and installed into the current Python path. This has some advantages over getting your packages strictly through your distro package manager (say yum or apt). This is especially true for developers deploying webservices, or really any other situation where you might want to have multiple versions of Python, or multiple versions of applications that require different versions of the same package. I could, for example, create multiple virtual environments (which is a way for Python to make a copy of it's core binaries, minus the global modules) and have each environment run a different version of a specific module. Or commonly, to set up a testing environment in parallel to your production environment to make sure that a newer module version doesn't break everything. As for packaging, an egg file is a Python format that really is just a zip file -- containing all the Python source code, dependencies, and other info about the module. They get dropped in your site-packages folder (or on Ubuntu, dist-packages since they like to be different). So to get specific, when I use apt to install python-ceph via "apt-get install python-ceph", it's essentially dropping rbd.py and rados.py into dist-packages. I can then go into Python and do "import rbd" or "import rados". However, dropping .py files into dist-packages can be improved upon. By building a proper Python package (in the form of an .egg), you can package it all up inside of a namespace like "ceph", and then your code is more like "from ceph import rbd" and "from ceph import rados". Or just "import ceph.rbd". Also, even though there is all the versioning from dpkg/apt involved, from a Python perspective, the .py files have no version. From within Python, there is no notion of what version of rbd.py I am using. Using a .egg can solve that. That would allow one to build other python modules that depend on package "ceph", such that you can say required "ceph >= 0.48.2" or similar. There are lots of examples of projects that distribute their modules both through distro repos and PyPI. OpenStack is a good example. If you do "apt-get install python-novaclient", it's going to to grab the package from archive.ubuntu.com (and stuff it into dist-packages). But if you do easy_install python-novaclient (or use pip), it's going to grab the latest from PyPI and stuff it into the site-packages folder of whatever Python path is currently active. Not sure if that touches on what you were looking for or not. Hope so. I know it'd be a big benefit to me! I think it would be a great way to promote the Python bindings. - Travis On Sat, Nov 3, 2012 at 12:31 PM, Gregory Farnum <greg@xxxxxxxxxxx> wrote: > On Fri, Nov 2, 2012 at 8:53 PM, Travis Rhoden <trhoden@xxxxxxxxx> wrote: >> Hi folks, >> >> Are there any plans to release python-ceph to pypi? It would be nice >> to see it packaged up in distutils/egg format and added to pypi, that >> way other python packages can list it as a dependency. >> >> I know there is currently a python-ceph package in Debian, but that >> doesn't allow me to list it as a dependency in a setup.py file and >> have it installed in a virtualenv, for example. Right now I have to >> copy rbd.py into my virtualenv. >> >> Curious to know if this is something you would consider. Perhaps it >> is something I could help with. > > I'm not familiar with Python packaging, can you talk about this a bit more? > -Greg > >> >> Thanks, >> >> - Travis >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
