envie 0.4.0

Bash helpers for navigating and managing Python VirtualEnvs.

envie is an ultra lightweight set of Bash functions aiming to increase your productivity when dealing with everyday VirtualEnv tasks, like: creating, destroying, listing and switching environments.

Summary

• mkenv [<env>|"env"] [<pyexec>|"python"] - Create virtualenv in <env> based on Python version <pyexec>.

• rmenv - Destroy the active environment.

• cdenv - Interactively activate the closest environment (looking down, then up, with lsupenv).

• lsenv [<start>|"." [<avoid>]] - List all environments below <start> directory, skipping <avoid> subdir.

• lsupenv - Find the closest environments by first looking down and then dir-by-dir up the tree, starting with cwd.

• envie init - Run (once) to enable (faster) searches with locate.

• envie update - Run to re-index directories searched with updatedb.

• envie register | unregister - Add/remove source statement to/from your .bashrc.

Examples

Create/destroy

To create a new VirtualEnv in the current directory, just type mkenv <envname>. This results with new environment created and activated in ./<envname>. When done with this environment, just type rmenv to destroy the active env.

stevie@caracal:~/demo$ ls
stevie@caracal:~/demo$ mkenv env
Creating python environment in 'env'.
Using Python 2.7.9 (/usr/bin/python).
(env)stevie@caracal:~/demo$ ls
env
(env)stevie@caracal:~/demo$ pip freeze
argparse==1.2.1
wsgiref==0.1.2
(env)stevie@caracal:~/demo$ rmenv
stevie@caracal:~/demo$ ls
stevie@caracal:~/demo$

Change/activate environment

Use cdenv to activate the closest environment, tree-wise. We first look down the tree, then up the tree. If a single Python environment is found, it’s automatically activated. In case the multiple environments are found, a choice is presented to user.

stevie@caracal:~/demo$ ls -F
env/ project/ file1 file2 ...
stevie@caracal:~/demo$ cdenv
(env)stevie@caracal:~/demo$

Assume the following tree exists:

~/demo
  |_ project1
  |  |_ env
  |  |  |_ ...
  |  |_ src
  |     |_ ...
  |_ project2
  |  |_ env
  |     |_ ...

Now, consider you work in ~/demo/project1/src/deep/path/to/module, but keep the environment in the env parallel to src. Instead of manually switching to env and activating it with something like source ../../../../../env/bin/activate, just type cdenv (cde<TAB> should actually do it, if you use tab completion):

stevie@caracal:~/demo/project1/src/deep/path/to/module$ cdenv
(env)stevie@caracal:~/demo/project1/src/deep/path/to/module$ which python
/home/stevie/demo/project1/env/bin/python

On the other hand, if there are multiple environments to choose from, you’ll get a prompt:

stevie@caracal:~/demo$ cdenv
1) ./project1/env
2) ./project2/env
#? 2
(env)stevie@caracal:~/demo$ which python
/home/stevie/demo/project2/env/bin/python

Search/list environments

To search down the tree for valid Python VirtualEnvs, use lsenv. Likewise, to search up the tree, level by level, use lsupenv. cdenv uses lsupenv when searching to environment to activate.

Install

For convenience, envie is packaged and distributed as a Python package. To install, simply type:

$ sudo pip install envie
$ envie register

The second line above will add a sourcing statement for envie to your .bashrc file.

Enable faster search

By default, envie uses the find command to search for environments. That approach is pretty fast when searching shallow trees. However, if you have a deeper directory trees, it’s often faster to use a pre-built directory index (i.e. the locate command). To enable a combined locate/find approach to search, run:

$ envie init
Indexing environments in '/home/stevie'...Done.

In the combined approach, if find doesn’t finish within 100ms, search via find is aborted and locate is allowed to finish (faster).