python

#!/usr/bin/env bash

ROOT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" || exit; pwd)

OPY_PATH=$(which opy 2> /dev/null)
PYTHON3_PATH=$(which python3 2> /dev/null)
PYTHON_PATH=$(which python 2> /dev/null)

function run_base_python
{
    if [[ -x "$OPY_PATH" ]]; then
        "$OPY_PATH" "$@"
    elif [[ -x "$PYTHON3_PATH" ]]; then
        "$PYTHON3_PATH" "$@"
    elif [[ -x "$PYTHON_PATH" ]]; then
        "$PYTHON_PATH" "$@"
    else
        echo "The python executable could not be found." 1>&2
        exit 1
    fi
}

VENV_HOME=$ROOT_DIR/.venv
VENV_PYTHON=$VENV_HOME/bin/python3

if [[ ! -d "$VENV_HOME" ]]; then
    run_base_python -m venv "$VENV_HOME"
    if [[ -x "$VENV_PYTHON" ]]; then
        "$VENV_PYTHON" -m pip install -r "$ROOT_DIR/requirements.txt"
    fi
fi
if [[ ! -x "$VENV_PYTHON" ]]; then
    echo "The venv's python executable could not be found." 1>&2
    exit 1
fi

export PYTHONPATH
PYTHONPATH=$ROOT_DIR:$PYTHONPATH

"$VENV_PYTHON" "$@"