envie 0.4.4

Bash helpers for navigating and managing Python VirtualEnvs.

At its core, envie is a set of Bash functions aiming to increase your productivity when dealing with mundane VirtualEnv tasks, like: creating, destroying, listing, switching and activating environments.

But envie really shines when it comes to auto-discovery and auto-activation of VirtualEnvs relevant to your project (or executable). Just say:

~/work/project-x$ envie manage.py migrate

~/work/project-y$ envie python tests.py

~$ envie python playground/plucky/tests/tests.py

or use it in a hash bang:

#!/usr/bin/env envie
import os
print(os.getenv("VIRTUAL_ENV"))

and in each of these cases the Python script will be executed in the closest virtual environment (for the definition of the closest environment see below, section Change/activate environment).

Summary

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

• rmenv - Destroy the active environment.

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

• lsenv [-f|-l] [<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.

• cdenv - cd to the base dir of the currently active virtualenv ($VIRTUAL_ENV).

• envie <script>, envie python <script> - Run python script in the closest virtual environment.

• envie exec <command> - Execute arbitrary command/builtin/file/alias/function in the closest virtual environment.

• 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 chenv 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$ chenv
(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 chenv (cde<TAB> should actually do it, if you use tab completion):

stevie@caracal:~/demo/project1/src/deep/path/to/module$ chenv
(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$ chenv
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. chenv uses lsupenv when searching for 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 400ms, search via find is aborted and locate is allowed to finish (faster).

To re-index environments, run:

$ envie update

To force find or locate, use -f and -l flags of lsenv.