python - How to source virtualenv activate in a Bash script

Question

How do you create a Bash script to activate a Python virtualenv?

I have a directory structure like:

.env
    bin
        activate
        ...other virtualenv files...
src
    shell.sh
    ...my code...

I can activate my virtualenv by:

user@localhost:src$ . ../.env/bin/activate
(.env)user@localhost:src$

However, doing the same from a Bash script does nothing:

user@localhost:src$ cat shell.sh
#!/bin/bash
. ../.env/bin/activate
user@localhost:src$ ./shell.sh
user@localhost:src$ 

What am I doing wrong?

Answer 1

When you source, you're loading the activate script into your active shell.

When you do it in a script, you load it into that shell which exits when your script finishes and you're back to your original, unactivated shell.

Your best option would be to do it in a function

activate () {
  . ../.env/bin/activate
}

or an alias

alias activate=". ../.env/bin/activate"

Hope this helps.