Pharo image download/preparation script

new-image.sh

#!/bin/bash
#
# Easier project setup for Pharo + Iceberg + Git.
#
# This script (re)downloads and prepares a ready-to-hack Pharo image, getting all
# necessary info from a small config file committed among the project's files.
#
set -euo pipefail
IFS=$'\n\t'
# ↑ bash strict mode http://redsymbol.net/articles/unofficial-bash-strict-mode/

function die { echo "$@" 1>&2; exit 1; }

function download_to {
    [[ $# -eq 2 ]] || "Usage: ${FUNCNAME[0]} filename url"
    local dest="$1" url="$2"

    curl --silent --location --compressed --output "$dest" "$url"
    # or the same with wget
}

function pharo_fetch_image {
    [[ $# -eq 1 ]] || die "Usage: ${FUNCNAME[0]} url"
    local url="$1" downloaded tmp

    # cache in a known place and continue?
    tmp=$(mktemp -dt "pharo.XXXXXX") # should get cleaned up automatically
    download_to "${tmp}/image.zip" "$url"
    unzip -q "${tmp}/image.zip" -d "$tmp"

    downloaded="$(ls "${tmp}"/*.image)" # ensures the image file exists
    downloaded="${downloaded%.image}"
    echo "$downloaded"
}

function pharo_rename {
    [[ $# -ge 2 ]] || die "Usage: ${FUNCNAME[0]} [--copy] original new"
    local copy='mv'
    [[ "$1" = '--copy' ]] && { copy='cp'; shift; }
    local original="$1" new="$2"

    [ -e "${original}.image" ] || die "No original image: ${original}.image"
    [ ! -e "${new}.image" ] || die "Destination file already exists: ${new}.image"
    [ ! -e "${new}.changes" ] || die "Destination file already exists: ${new}.changes"

    "$copy" "${original}.image" "${new}.image"
    "$copy" "${original}.changes" "${new}.changes"
}

function pharo_delete {
    [[ $# -ge 1 ]] || die "Usage: ${FUNCNAME[0]} basename..."

    # while [[ $# -ge 1 ]]; do
    #     local name="$1"
    #     shift
    for name in "$@"; do
        rm -f "${name}.image"
        rm -f "${name}.changes"
    done
}

function pharo_backup {
    [[ $# -eq 1 ]] || die "Usage: ${FUNCNAME[0]} name"
    local name="$1" backup_stamp
    backup_stamp="backup-$(date +%Y%m%d-%H%M)"

    shopt -s nullglob
    for image in ${name}-*.image; do # match any hash
        image="${image%.image}"
        pharo_rename "${image}" "${image}.${backup_stamp}"
    done
}

function pharo_load {
    [[ $# -eq 2 ]] || die "Usage: ${FUNCNAME[0] script image}"
    local script="$1" image="$2"

    for script_file in "load.st" "${script}.load.st" "local.st" "${script}.local.st"; do
        if [[ -e "$script_file" ]]; then
            ${PHARO} "${image}.image" st --save --quit "$script_file"
        fi
    done
}

function pharo_prepare {
    [[ $# -eq 3 ]] || die "Usage: ${FUNCNAME[0] base script new}"
    local base="$1" script="$2" new="$3"

    pharo_rename --copy "$base" "$new"
    cp -f "${base}.sources" "$(dirname "$new")"
    pharo_load "$script" "$new"
}

function pharo_build_image {
    # Ensure environment variables have sensible values.
    # You can use direnv to overrides
    : "${PHARO_PROJECT:=pharo}"
    : "${PHARO:=./pharo-ui}"
    : "${PHARO_VERSION:=70}"
    : "${PHARO_FILES:="http://files.pharo.org/get-files/${PHARO_VERSION}"}"

    local fetched hash
    local -a images=("$@")

    [[ ${#images[@]} -eq 0 ]] && read -ra images < <( ls ./*.load.st )
    [[ ${#images[@]} -eq 0 ]] && images=( "$PHARO_PROJECT" )
    images=( "${images[@]%.load.st}" )

    fetched="$(pharo_fetch_image "${PHARO_FILES}/pharo.zip")"
    hash="${fetched##*-}" # strip everything but the short hex hash

    for project in "${images[@]}"; do
        pharo_delete "${project}.tmp"
        pharo_prepare "$fetched" "$project" "${project}.tmp"
    done

    for project in "${images[@]}"; do
        pharo_backup "${project}"
        pharo_rename "${project}.tmp" "${project}-${hash}"
    done
}

# run if called as a command, else we're being sourced as a library
if [[ "${BASH_SOURCE[0]}" == "$0" ]]; then
    pharo_build_image "$@"
fi