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pythoninstallationvirtualenvironment

Installing pigpio into a virtual environment

I wanted to ask on how I can install a library appropriately in a virtual environment. I am currently having difficulties using a Servo library called pigpio upon installation when I activate a virtual environment on my Raspberry Pi Zero W.

The problem arise if I leave out ‘sudo’ in my bash commands in terminal (i.e.python myscript.py) since using the command ‘sudo python myscript.py’ would render another module of this script (Boto3) unavailable in the virtual environment.

The error message when I used the sudo command goes: Traceback (most recent call last): File "myscript.py", line 13, in import pigpio ImportError: No module named Boto3

On the other hand, using a non-sudo bash command results in pigpio, the Servo library module being unavailable.

I suspect the problem lies in the process of installation of pigpio library as I had to use ‘sudo make install’ in one of the steps. I think I might need to install via an alternative method that avoids global installation i.e. sudo. My understanding is that only pip can install packages into a virtualenv (from Pypi) (v.s. sudo which leads to global installation). Is there a way that I can find another way to appropriately install a library into a virtual environment?

Solution

  • The easiest way would be to uninstall all dependencies from the system wide modules: 

    sudo pip uninstall boto3 pigpio

    cd to a directory like /home/your_user and then retry installing the dependencies in the venv like:

    virtualenv venv_test
source venv_test/bin/activate
pip install boto3
cd pigpio

    Maybe a hacky edit to https://github.com/joan2937/pigpio/blob/master/Makefile#L34 to be inside your venv folder? like $(pwd)/venv_test:

    make
make install
deactivate
source venv_test/bin/activate

    It can get complicated with permissions and module paths if using --system-site-packages or something similar.

    Also be sure that you have permissions in the directory where the venv folder is. so like if you ls -ail . you should see the non-sudo user has chown craver2000:craver2000 the_dir

    You may also be able to do something like:

    sudo cp -R /path/to/dist-packages/pigpio venv_test/lib/python2.7/site-packages
sudo chown -R $USER venv_test/lib/python2.7/site-packages

    And upon further examination you might be able to just copy the pigpio file to your virtualenv like:

    deactivate
cp pigpio/pigpio.py venv_test/lib/python2.7/site-packages
source venv_test/bin/activate

    And digging a bit more here is an untested install, but hey the module imports using a venv :):

    162  sudo apt-get install build-essential
  163  git clone https://github.com/joan2937/pigpio.git
  164  pip
  165  pip install virtualenv
  166  python -m pip install virtualenv
  167  sudo pip install virtualenv
  168  sudo pip install --upgrade pip
  169  virtualenv
  170  virtualenv venv_test
  171  cd pigpio/
  172  ls
  173  nano Makefile
  174  make
  175  make install
  176  mkdir /opt/pigpio
  177  sudo mkdir /opt/pigpio
  178  chown $USER /opt/pigpio
  179  sudo chown $USER /opt/pigpio
  180  make install
  181  source ../venv_test/bin/activate
  182  ls
  183  make install
  184  sudo mkdir /usr/lib/python3.5/site-packages
  187  sudo chown $USER /usr/lib/python3.5/site-packages
  211  sudo chmod 4755 /sbin/ldconfig
  213  sudo chmod 4755 /sbin/ldconfig.real
  214  make install
  215  history