python3 --version
Python 3.7.3

pip3 install virtualenv
...
Collecting virtualenv
...
Successfully installed distlib-0.3.1 filelock-3.0.12 virtualenv-20.2.1

sudo apt install python3-pip python3-dev python-setuptools python-virtualenv git libyaml-dev build-essential

git clone https://github.com/foosel/OctoPrint.git

wf@pito:~/source/python/OctoPrint $ virtualenv venv
Running virtualenv with interpreter /usr/bin/python2
New python executable in /home/wf/source/python/OctoPrint/venv/bin/python2
Also creating executable in /home/wf/source/python/OctoPrint/venv/bin/python
Installing setuptools, pkg_resources, pip, wheel...done.

wf@pito:~/source/python/OctoPrint $ ./venv/bin/python setup.py install
...
Using /home/wf/OctoPrint/venv/lib/python3.7/site-packages
Finished processing dependencies for OctoPrint==1.5.1

./venv/bin/octoprint serve

sudo apt-get -y install gcc-4.7 g++-4.7
git clone -b legacy https://github.com/Ultimaker/CuraEngine.git
cd CuraEngine
make

sudo apt-get install libjpeg-dev libjpeg8-dev imagemagick libav-tools cmake
git clone https://github.com/jacksonliam/mjpg-streamer.git
cd mjpg-streamer/mjpg-streamer-experimental
make

[Desktop Entry]
Type=Application
Name=OctoPrint
Comment=OctoPrint service
NoDisplay=true
Exec=/home/wf/bin/octoprint

sudo usermod -a -G dialout $(whoami)

#!/bin/bash
# WF 2019-02-24
# Octoprint startup script

# set these variables according to your installation
mjpg=$HOME/source/cpp/mjpg-streamer
mjpg_port=8080
octo=$HOME/source/python/OctoPrint

#
# check whether the given process runs
# param #1: l_process  - the process to check
#
check_run() {
  local l_process="$1"
  pgrep -fl "$l_process"
  local l_presult=$?
  if [ $l_presult -eq 0 ]
  then
    echo "$l_process already running"
    # comment out as you like
    # either stop here
    #echo "to kill the process you might want to use"
    #echo "pkill -f $l_process"    
    #exit 1
    # or fully automatic kill
    echo "killing $l_process" 
    pkill -f "$l_process"    
  fi
}

#
# make sure the given logfile exists and is accessible
# param #1: l_logfile
#
prepare_log() {
  local l_logfile=$1
  sudo touch $l_logfile
  sudo chown $(whoami) $l_logfile
}

#
# start the webcam streamer
#
start_streamer() {
  check_run  mjpg_streamer
  cd $mjpg/mjpg-streamer-experimental
  log=/var/log/mjpeg_streamer.log
  prepare_log $log
  echo "starting mjpg_streamer logging to $log"
  nohup ./mjpg_streamer -i "input_uvc.so -d /dev/video0 -r 1920x1080" -o "output_http.so -p $mjpg_port -w ./www" >> $log 2>&1 &
}


#
# start octoprint
#
start_octoprint() {
  check_run "octoprint serve"
  log=/var/log/octoprint.log
  prepare_log $log
  cd $octo
  echo "starting octoprint logging to $log"
  nohup ./venv/bin/octoprint serve >> $log 2>&1 &
}

start_streamer
start_octoprint