Description

When you have virtualenv installed trough pip in Arch Linux, the ./dev_setup.sh script does not works. The installation of python-virtualenvwrapper breaks because the files already exists. The ideal solution is to fix python-virtualenvwrapper installation for Arch. For now, the Mycroft setup script can check if the lib is already installed and skip it.

Update:

Actually, we do not need virtualenv anymore for Mycroft, the ideal solution is to remove this dependency.

This is related to "Error installing dependencies using pacman on Arch linux" #1967

How to test

Simulating the error

Create a Dockerfile with the following code:

FROM archlinux:20191105
RUN pacman -Sy --needed --noconfirm python python-pip
RUN pip install virtualen
RUN pacman -S --needed --noconfirm python-virtualenvwrapper

Try to build the Dockerfile with docker build .. You should see something like:

python-virtualenv: /usr/bin/virtualenv exists in filesystem
python-virtualenv: /usr/lib/python3.8/site-packages/__pycache__/virtualenv.cpython-38.pyc exists in filesystem
python-virtualenv: /usr/lib/python3.8/site-packages/virtualenv.py exists in filesystem
python-virtualenv: /usr/lib/python3.8/site-packages/virtualenv_support/__init__.py exists in filesystem
python-virtualenv: /usr/lib/python3.8/site-packages/virtualenv_support/__pycache__/__init__.cpython-38.pyc exists in filesystem
Errors occurred, no packages were upgraded.
The command '/bin/sh -c pacman -S --needed --noconfirm python-virtualenvwrapper' returned a non-zero code: 1

Simulating the solution

Create a Dockerfile with the following code:

FROM archlinux:20191105
RUN pacman -Sy --needed --noconfirm python python-pip
RUN pip install virtualenv

RUN command -v virtualenv &> /dev/null || ( \
		pacman -S --needed --noconfirm python-virtualenvwrapper\
	)

RUN virtualenv --version

Try to build the Dockerfile with docker build .. You should see something like:

 ---> Running in 0f04d3148914
16.7.8
Removing intermediate container 0f04d3148914
 ---> c14897eb88c1
Successfully built c14897eb88c1

The 16.7.8 message shows that the virtualenv is instaled in the version 16.7.8.

Real testing

Using an Arch Linux installation, install the virtualenv with pip running pip install virtualenv. Try to run the ./dev_setup.sh after that. The setup should finish with success, and you should be able to start Mycroft. I have tested the solution on my machine (Manjaro Linux) and works ok.