virtualenvwrapper functions unavailable in shell s

问题:

So, once again, I make a nice python program which makes my life ever the more easier and saves a lot of time. Ofcourse, this involves a virtualenv, made with the mkvirtualenv function of virtualenvwrapper. The project has a requirements.txt file with a few required libraries (requests too :D) and the program won't run without these libraries.

I am trying to add a bin/run-app executable shell script which would be in my path (symlink actually). Now, inside this script, I need to switch to the virtualenv before I can run this program. So I put this in

#!/bin/bash
# cd into the project directory
workon "$(cat .venv)"
python main.py

A file .venv contains the virtualenv name. But when I run this script, I get workon: command not found error.

Of course, I have the virtualenvwrapper.sh sourced in my bashrc but it doesn't seem to be available in this shell script.

So, how can I access those virtualenvwrapper functions here? Or am I doing this the wrong way? How do you launch your python tools, each of which has its own virtualenv!?

回答1:

Just source the virtualenvwrapper.sh script in your script to import the virtualenvwrapper's functions. You should then be able to use the workon function in your script.

And maybe better, you could create a shell script (you could name it venv-run.sh for example) to run any Python script into a given virtualenv, and place it in /usr/bin, /usr/local/bin, or any directory which is in your PATH.

Such a script could look like this:

#!/bin/sh
# if virtualenvwrapper.sh is in your PATH (i.e. installed with pip)
source `which virtualenvwrapper.sh`
#source /path/to/virtualenvwrapper.sh # if it's not in your PATH
workon $1
python $2
deactivate

And could be used simply like venv-run.sh my_virtualenv /path/to/script.py

回答2:

I can't find the way to trigger the commands of virtualenvwrapper in shell. But this trick can help: assume your env. name is myenv, then put following lines at the beginning of scripts:

ENV=myenv
source $WORKON_HOME/$ENV/bin/activate

回答3:

It's a known issue. As a workaround, you can make the content of the script a function and place it in either ~/.bashrc or ~/.profile

function run-app() {
  workon "$(cat .venv)"
  python main.py
} 

回答4:

If your Python script requires a particular virtualenv then put/install it in virtualenv's bin directory. If you need access to that script outside of the environment then you could make a symlink.

main.py from virtualenv's bin:

#!/path/to/virtualenv/bin/python
import yourmodule

if __name__=="__main__":
   yourmodule.main()

Symlink in your PATH:

pymain -> /path/to/virtualenv/bin/main.py

In bin/run-app:

#!/bin/sh
# cd into the project directory
pymain arg1 arg2 ...

回答5:

Apparently, I was doing this the wrong way. Instead of saving the virtualenv's name in the .venv file, I should be putting the virtualenv's directory path.

(cdvirtualenv && pwd) > .venv

and in the bin/run-app, I put

source "$(cat .venv)/bin/activate"
python main.py

And yay!

回答6:

add these lines to your .bashrc or .bash_profile

export WORKON_HOME=~/Envs
source /usr/local/bin/virtualenvwrapper.sh

and reopen your terminal and try

回答7:

You can also call the virtualenv's python executable directly. First find the path to the executable:

$ workon myenv
$ which python
/path/to/virtualenv/myenv/bin/python

Then call from your shell script:

#!/bin/bash

/path/to/virtualenv/myenv/bin/python myscript.py

回答8:

This is a super old thread and I had a similar issue. I started digging for a simpler solution out of curiousity.

gnome-terminal --working-directory='/home/exact/path/here' --tab --title="API" -- bash -ci "workon aaapi && python manage.py runserver 8001; exec bash;"

The --workingdirectory forces the tab to open there by default under the hood and the -ci forces it to work like an interactive interface, which gets around the issues with the venvwrapper not functioning as expected.

You can run as many of these in sequence. It will open tabs, give them an alias, and run the script you want.

Personally I dropped an alias into my bashrc to just do this when I type startdev in my terminal.

I like this because its easy, simple to replicate, flexible, and doesn't require any fiddling with variables and whatnot.