virtualenvutils 0.1.4

manage virtualenv based utilities

You can manage virtualenv based utilities with this utility. Its primary (and initial) use is to generate Bash alias`es for utilities that are installed in separate virtualenvs. In such a setup, you don’t want to extend your path with the ``bin` directory of each of the virtualenvs, as that gives you:

• a long PATH

• multiple python executables in your PATH

• all utilties that are a result of installing some Python package dependency and for which you might want to use a different version (or not all).

virtualenvutils alias dir1 dir2 scans directories, non-recursive, under dir1`, ``dir2 for virtualenvs. Any directory containing bin, lib, include subdirectories as well as a file bin/activate is considered a virtualenv.

For any of those virtualenvs it does one of following (checked in this order):

• if there is a virtualenvutils.conf file it is loaded to determine the utilties and possibly their mapping.

• if the name of the directory under dir1, etc., is e.g. do_xyx, and dir1/do_xyz/bin/do_xyz exists and is executable then this is the utility

• if there is no matching name, then all of the executable files under bin except those matching activate*, easy_install*, pip*, python*, wheel* are considered utilities, unless they have extensions matching “.so”, “.py”, or “.pyc”.

the utility then generates aliases for all utilities found this way, making sure they are unique if added by the last method, and writes those alias definitions to stdout. Any error go to stderr.

Other functionalities include:

• updating all packages for all virtualenvs

see virtualenvutils --help for the full list of subcommands

virtualenvutils.conf

The virtualenvutils.conf file, if provided, has to be in the toplevel directory of the virtualenv (i.e. next to bin, include and lib and consist of single line with or without a colon (:).

If there is no colon, then the line is considered to be the name of an executable file under that virtualenvs bin.

If there is a colon, the part before the colon is considered the name for executable under bin, for which the executable name is the part behind the colon.

Example

You want to install docker-compose in a virtualenv. If you do:

mkvirtualenv -p /opt/python3/bin/python /opt/util/docker-compose
source !$/bin/activate
pip install docker-compose
deactivate
virtualenvutils alias /opt/util

you will get:

alias docker-compose='/opt/util/docker-compose/bin/docker-compose'

If you would have specified a different final directory:

mkvirtualenv -p /opt/python3/bin/python /opt/util/compose
source !$/bin/activate
pip install docker-compose
deactivate
virtualenvutils alias /opt/util

you will get:

alias docker-compose='/opt/util/compose/bin/docker-compose'
alias jsonschema='/opt/util/compose/bin/jsonschema'

In either of these two examples you can force the way the aliases are generated (the example is based on the first):

echo 'dc:docker-compose' > /opt/util/docker-compose/virtualenvutils.conf
virtualenvutils alias /opt/util

you will get:

alias dc='/opt/util/docker-compose/bin/docker-compose'

and if you then append:

echo 'docker-compose' >> /opt/util/docker-compose/virtualenvutils.conf

will get you:

alias dc='/opt/util/docker-compose/bin/docker-compose'
alias docker-compose='/opt/util/docker-compose/bin/docker-compose'

Usage .bashrc

You would normally put something like:

/opt/util/virtualenvutils/bin/virtualenvutils alias /opt/util/ > /tmp/$$.alias
source /tmp/$$.alias
rm -f /tmp/$$.alias

in your ~/.bashrc to get the appropriate aliases loaded (of course assuming that you installed virtualenvutils in a virtualenv /opt/util/virtualenvutils, which is not necessary, as long as bash can find the utility).

Updating existing virtualenvs

You can update all packages for all virtualenv utilities by using:

virtualenvutils update /opt/util

Installing a new util

You can install one or more new virtualenv based utilities using something like:

virtualenvutils install /opt/util/{docker-compose,ruamel.yaml.cmd}

virtualenv has to be in your path for this, you can use --pkg to give a package name that differs from the final part of the path (in which case you can of course only specify one path), and with --python /opt/python/3/bin/python you can explicitly specify the python version to use.

Don’t forget that you probably have to logout and login for if you set your aliases through as scan initiated in .bashrc, before you can use the commands.