[SOLVED] Writing Shell Commands to VirtualEnv?

Issue

I hope this isn't a silly question...but, is there a way I can write commands to a virtual environment after it's been activated? For example lets say I have a Python or Bash script which does some, stuff i.e. make a virtualenv, 2. Activates it. Then 3. Executes the commands to the shell of the newly created virtual environment? For example I am doing something like this:

activate_this = subprocess.call("/bin/bash --rcfile " + "/home/" + os.getlogin() + "/mission-control/venv/bin/activate", shell=True)
        process = execfile(activate_this, dict(__file__=activate_this))
        process.communicate(subprocess.call(virtualenv.create_bootstrap_script(textwrap.dedent
            ("""
                import subprocess
                subprocess.call("pip install -r " + os.environ['VIRTUAL_ENV'] + "/requirements.txt", shell=True)
            """
            ))))

I would like to install the requirements.txt file after I activate the environment however I can't get the subprocess module to communicate with the shell after the virtual environment is created. I think it might have to do with me creating a new virtual environment via execfile, which therefore is creating a new process. Thanks in advanced!

Also I know shell=True is bad practice but as of right now I am not concerned with the possibility of unsanitized input.

Solution

First of all, thanks to @Ryne Everett for the help. So I solved this by just ditching the Python solution and creating a Bash file which I call from subprocess in my Python script. The subprocess call executes the Bash file which handles creating and executing within the virtualenv. I am not sure how to solve this using just Python. I am sure there is a way but this seems like a simpler solution. The Bash script is the following:

#!/bin/bash 

MISSION_CONTROL="$PWD"

if [ ! -d "$MISSION_CONTROL/venv" ]; then 
    virtualenv $MISSION_CONTROL/venv --no-site-packages
    echo "Welcome to Mission Control..."
    /bin/bash --rcfile $MISSION_CONTROL/venv/bin/activate
fi 

if [ -d "$MISSION_CONTROL/venv" ]; then 
    pip install -r $MISSION_CONTROL/requirements.txt 
fi

EDIT: This may also be useful for people who are trying to do something similiar: How to source virtualenv activate in a Bash script

Answered By - user2808315