Patch a Krita appimage with a pip package

krita-pip.sh

#!/usr/bin/env bash
# Add pip packages to a Krita .appimage
# - as descriped here https://gist.github.com/Larpon/e81ed68895bdba35098d9d84688ac01e
#
# The script is working on a copy of the appimage to ensure any failed
# runs doesn't make your krita unusable
# You can patch an appimage multiple times

# TODO support installing multiple packages in one go

SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
SCRIPT_NAME="$(basename "$0")"

export PID=$$
_PWD=$(pwd)
VERSION=0.1

_PIP_PACKAGE=""

col() {
    if [[ $# -eq 0 ]] ; then return; fi

    local c=$1
    local nocolor="\033[0m"
    local color="$nocolor"

    # More colors at https://misc.flogisoft.com/bash/tip_colors_and_formatting
    if [ $c == "black" ]; then color="\e[30m"; fi
    if [ $c == "red" ]; then color="\e[31m"; fi
    if [ $c == "green" ]; then color="\e[32m"; fi
    if [ $c == "yellow" ]; then color="\e[33m"; fi
    if [ $c == "blue" ]; then color="\e[34m"; fi
    if [ $c == "magenta" ]; then color="\e[35m"; fi
    if [ $c == "cyan" ]; then color="\e[36m"; fi
    if [ $c == "light-grey" ] || [ $c == "grey" ]; then color="\e[37m"; fi
    if [ $c == "dark-grey" ]; then color="\e[90m"; fi
    if [ $c == "white" ]; then color="\e[97m"; fi
    echo -e "${color}${2}${nocolor}"
}

info() {
    echo -e "[$(col blue "INFO")] "$@
}

error() {
    >&2 echo -e "[$(col red "ERROR")] "$@
}

strip_slashes() {
    local stripped="$1"
    case $stripped in
        *[!/]*/) stripped=${stripped%"${stripped##*[!/]}"};;
    esac
    echo "$stripped"
}

ensure_path() {
    if [ ! -d "$1" ]; then
        mkdir -p "$1"
    fi
}

temp_path()
{
    local _tmp_path="/tmp/krita-pip/$1"
    ensure_path "$_tmp_path"
    echo "$(strip_slashes "$_tmp_path")"
}

cmdavail () {
    command -v "$1" >/dev/null 2>&1
}

check() {
    cmdavail $1 || { error >&2 "$2"; exit 1; }
}

trap "exit 1" TERM
die() {
    error $@
    kill -s TERM $PID
}

rms() {
    local _dir="$1"
    if [ -e "$_dir" ] && [ "$_dir" != "" ] && [ "$_dir" != "/" ]; then
        info "Removing \"$1\""
        cd "$1" && rm -rf * && cd "$_PWD"
    fi
}

usage() {
cat << EOF
VERSION: $VERSION
USAGE:
    $SCRIPT_NAME [options]

DESCRIPTION:
    Patch a Krita appimage

AUTHOR:
    Lars Pontoppidan <dev.larpon@gmail.com>

LICENSE:
    MIT license

OPTIONS:

    -h
        Print this message and exit

    -p <package_name>
        Name of pip package to add to the Krita image

EXAMPLES:
    * Patch a Krita .appimage with PIL (Pillow)
    # $SCRIPT_NAME -p pillow ./krita-4.1.7-x86_64.appimage

EOF
}

check appimagetool "This tool requires \"appimagetool\" (https://github.com/AppImage/AppImageKit)"
check pyenv "This tool requires \"pyenv\" (https://github.com/pyenv/pyenv-installer)"

while getopts ":hp:" OPTION
do
    case $OPTION in
        h ) usage && exit 0 ;;
        p ) _PIP_PACKAGE=$OPTARG ;;
        * ) usage; die "One or more options not recognized..." ;; # DEFAULT
    esac
done
shift "$(($OPTIND - 1))" # Move argument pointer to next argument.

_KRITA_APPIMAGE="$1"
rms "$(temp_path)"
if [ -f "$1" ]; then
    info "Copying \"$_KRITA_APPIMAGE\" to $(temp_path) for patching"
    cp "$1" "$(temp_path)/"
else
    die "Please provide a valid path to a Krita appimage (\"$_KRITA_APPIMAGE\" does not exist)"
fi

cd "$(temp_path)"

_KRITA_APPIMAGE="$(temp_path)/$( basename "$_KRITA_APPIMAGE" )"
info "Extracting \"$_KRITA_APPIMAGE\" to $(temp_path) for patching"
$_KRITA_APPIMAGE --appimage-extract
_KRITA_EXTRACTED_PATH="$(temp_path)/squashfs-root"

_PYTHON_ENV="$(temp_path "py")"
info "Setting up python env in \"$_PYTHON_ENV\""
cd "$_PYTHON_ENV"

# TODO auto-detect krita python version
pyenv install 3.5.2
pyenv local 3.5.2

info "Installing \"$_PIP_PACKAGE\""
pip install $_PIP_PACKAGE

info "Copying to Krita work directory"
cp -r "$PYENV_ROOT/versions/3.5.2/lib/python3.5/site-packages" "$_KRITA_EXTRACTED_PATH/usr/lib/python3.5/"

info "Removing Krita copy $_KRITA_APPIMAGE"
rm "$_KRITA_APPIMAGE"
info "Re-packaging patched Krita"
appimagetool "$_KRITA_EXTRACTED_PATH" "$_KRITA_APPIMAGE"
chmod +x "$_KRITA_APPIMAGE"
info "Patched Krita image written to $_KRITA_APPIMAGE"
info "Have a productive time!"