setup_env.sh

#!/bin/bash

SCRIPT_DIR="$(cd "$(dirname "$0")"; pwd -P)"
VIRTUALENV_DIR="${SCRIPT_DIR}/env"

SED=$([[ $(command -v gsed) ]] && echo -n "gsed" || echo -n "sed")

if [ -z "${PYTHON_EXECUTABLE}" ]; then
	if [[ $(command -v python3) ]]; then
		PYTHON_EXECUTABLE=python3
	elif [[ $(command -v python) ]]; then
		PYTHON_VERSION=$(python --version 2>&1 | $SED -r 's/^Python //g')
		PYTHON_VERSION_MAJOR=$(echo "${PYTHON_VERSION}" | cut -d'.' -f1)
		if [ "${PYTHON_VERSION_MAJOR}" -lt 3 ]; then
			echo "Required Python version is at least 3.0 (yours is ${PYTHON_VERSION}). Please install appropriate version of Python or set PYTHON_EXECUTABLE in your environment to your Python interpreter." >&2
			exit 1
		fi
		PYTHON_EXECUTABLE=python
	else
		echo "Could not locate Python with any known name (python3, python). Make sure you have Python 3+ installed and set PYTHON_EXECUTABLE in your environment to your Python interpreter." >&2
		exit 1
	fi
else
	PYTHON_VERSION=$(${PYTHON_EXECUTABLE} --version 2>&1 | $SED -r 's/^Python //g')
	PYTHON_VERSION_MAJOR=$(echo "${PYTHON_VERSION}" | cut -d'.' -f1)
	if [ "${PYTHON_VERSION_MAJOR}" -lt 3 ]; then
		echo "Required Python version is at least 3.0 (yours is ${PYTHON_VERSION}). Please install appropriate version of Python or set PYTHON_EXECUTABLE in your environment to your Python interpreter." >&2
		exit 1
	fi
fi

if [[ $("${PYTHON_EXECUTABLE}" -c 'import venv;print("OK")' 2>/dev/null) ]]; then
	"${PYTHON_EXECUTABLE}" -m venv "${VIRTUALENV_DIR}"
elif [[ $(command -v virtualenv) ]]; then
	virtualenv -p "${PYTHON_EXECUTABLE}" "${VIRTUALENV_DIR}"
else
	echo "Neither venv or virtualenv found on your system. Please install one of these virtual environments for Python." >&2
	exit 1
fi

source "${SCRIPT_DIR}/use_env.sh"
pip install wheel
pip install -r "${SCRIPT_DIR}/requirements.txt"