Set-up installation script for virtual environment without usage of container.

video_prediction_tools/env_setup/install_venv.sh

+#!/usr/bin/env bash
+#
+# __authors__ = Bing Gong, Michael Langguth
+# __date__  = '2022_02_28'
+# __last_update__  = '2022_02_28' by Michael Langguth
+#
+# **************** Description ****************
+# This auxiliary script sets up the virtual environment OUTSIDE singularity container.
+# **************** Description ****************
+
+# set some basic variables
+BASE_DIR="$(pwd)"
+VENV_DIR=$1
+VENV_NAME="$(basename "${VENV_DIR}")"
+VENV_BASE="$(dirname "${VENV_DIR}")"
+WORKING_DIR="$(dirname "${VENV_BASE}")"
+VENV_REQ=${BASE_DIR}/requirements_nocontainer.txt
+
+# sanity checks
+
+# check if directory to virtual environment is parsed
+if [ -z "$1" ]; then
+  echo "ERROR: Provide a name to set up the virtual environment."
+  return
+fi
+
+# check if virtual environment is not already existing
+if [ -d "$1" ]; then
+  echo "ERROR: Target directory of virtual environment ${1} already exists. Chosse another directory path."
+  return
+fi
+
+# check for requirement-file
+if [ ! -f "${VENV_REQ}" ]; then
+  echo "ERROR: Cannot find requirement-file '${VENV_REQ}' to set up virtual environment."
+  return
+fi
+
+# get Python-version
+PYTHON_VERSION=$(python3 -c 'import sys; version=sys.version_info[:2]; print("{0}.{1}".format(*version))')
+
+# create or change to  base directory for virtual environment (i.e. where the virtualenv-module is placed)
+if ! [[ -d "${VENV_BASE}" ]]; then
+  mkdir "${VENV_BASE}"
+  # Install virtualenv in this directory
+  echo "Installing virtualenv under ${VENV_BASE}..."
+  pip install --target="${VENV_BASE}/" virtualenv
+  # Change into the base-directory of virtual environments...
+  cd "${VENV_BASE}" || return
+else
+  # Change into the base-directory of virtual environments...
+  cd "${VENV_BASE}" || return
+  if ! python -m virtualenv --version >/dev/null; then
+    echo "ERROR: Base directory for virtual environment exists, but virtualenv-module is unavailable."
+    exit
+  fi
+  echo "Virtualenv is already installed."
+fi
+
+
+# Set-up virtual environment in base directory for virtual environments
+python3 -m virtualenv "${VENV_NAME}"
+# Activate virtual environment and install required packages
+echo "Activating virtual environment ${VENV_NAME} to install required Python modules..."
+ACT_VENV="${VENV_DIR}/bin/activate"
+source "${VENV_DIR}/bin/activate"
+# set PYTHONPATH...
+export PYTHONPATH=${WORKING_DIR}/virtual_envs/${VENV_NAME}/lib/python${PYTHON_VERSION}/site-packages:$PYTHONPATH
+export PYTHONPATH=${WORKING_DIR}:$PYTHONPATH
+export PYTHONPATH=${WORKING_DIR}/utils:$PYTHONPATH
+export PYTHONPATH=${WORKING_DIR}/model_modules:$PYTHONPATH
+export PYTHONPATH=${WORKING_DIR}/postprocess:$PYTHONPATH
+# ... also ensure that PYTHONPATH is appended when activating the virtual environment...
+echo 'export PYTHONPATH='${WORKING_DIR}'/virtual_envs/'${VENV_NAME}'/lib/python'${PYTHON_VERSION}'/site-packages:$PYTHONPATH' >> ${ACT_VENV}
+echo 'export PYTHONPATH='${WORKING_DIR}':$PYTHONPATH' >> ${ACT_VENV}
+echo 'export PYTHONPATH='${WORKING_DIR}'/utils:$PYTHONPATH' >> ${ACT_VENV}
+echo 'export PYTHONPATH='${WORKING_DIR}'/model_modules:$PYTHONPATH' >> ${ACT_VENV}
+echo 'export PYTHONPATH='${WORKING_DIR}'/postprocess:$PYTHONPATH' >> ${ACT_VENV}
+# ... install requirements
+pip install --no-cache-dir -r "${VENV_REQ}"
+
+# get back to basic directory
+cd "${BASE_DIR}" || exit
+
+
+