bin/python-venv.sh

   1 #!/usr/bin/env bash
   2 set -eu
   3
   4 readonly requirements_file=$1
   5 shift
   6
   7 venv_dir="$(dirname "$requirements_file")"/.venv
   8 readonly venv_dir
   9 readonly venv_req=$venv_dir/requirements.txt
  10 readonly venv_python_version=$venv_dir/python-version.txt
  11
  12 if [ -d "$venv_dir" ]
  13 then
  14   if [ ! -r "$venv_python_version" ]
  15   then
  16     echo "Python environment predates Python version checks."
  17     echo "It might be invalid and needs to be regenerated."
  18     rm -rf "$venv_dir"
  19   elif ! cmp --quiet <(python --version) "$venv_python_version"
  20   then
  21     old=$(cat "$venv_python_version")
  22     new=$(python --version)
  23     echo "Python version has changed ($old -> $new)."
  24     echo "Python environment needs to be regenerated."
  25     unset old new
  26     rm -rf "$venv_dir"
  27   fi
  28 fi
  29
  30 if ! [ -r "$venv_dir/bin/activate" ]
  31 then
  32   echo "Creating Python environment..."
  33   python -m venv "$venv_dir"
  34   python --version > "$venv_python_version"
  35 fi
  36
  37 # shellcheck disable=1091
  38 source "$venv_dir/bin/activate"
  39
  40 if ! cmp --quiet "$requirements_file" "$venv_req"
  41 then
  42   echo "$(realpath --relative-to="$PWD" "$requirements_file") has changed, re-installing..."
  43   pip --disable-pip-version-check install --requirement "$requirements_file"
  44   cp "$requirements_file" "$venv_req"
  45 fi
  46
  47 python "$@"