Workaround for #1630

get-signal.sh

#!/usr/bin/env bash
#
# (c)2018 Christian Kujau <[email protected]>
# Get a fresh copy from https://signal.org/
#
# A (far too complicated) script to get the Ubuntu package of
# Signal on a non-Debian based Desktop, due to:
#
# > Packages for rpm-based linux distributions like Fedora #1630 
# > https://github.com/signalapp/Signal-Desktop/issues/1630
#
# PGP Key:
# https://pgp.key-server.io/pks/lookup?op=get&search=0xD980A17457F6FB06
#
set -e

BASEURL=https://updates.signal.org/desktop/apt
   DIST=dists/xenial
   DEST=/opt/Signal
umask 0022

# unset me!
# DEBUG=echo

# Kill it with fire
_die() {
	echo "$@"
	exit 1
}

# Sanity checks
command -v fzf > /dev/null || _die "### ERROR: fzf not found!"
command -v ar  > /dev/null || _die "### ERROR: ar not found!"

TEMP=$(mktemp -d)
trap 'rm -r ${TEMP}' EXIT INT TERM HUP
cd "$TEMP" || _die "Could not change to directory $TEMP"
echo "### URL: ${BASEURL}"

# Download & verify InRelease
if [ ! -f InRelease ]; then
	if curl -sLO "${BASEURL}/${DIST}/InRelease"; then
		echo "### Download ${DIST}/InRelease OK."
	else
		_die "### Download ${DIST}/InRelease FAILED."
	fi
fi

# Refresh keys once a month
if [ -f "${HOME}/.config/Signal/gpg.refresh" ]; then
	DIFF="$(( $(date +%s) - $(stat -c %Y "${HOME}/.config/Signal/gpg.refresh") ))"
	if [ ${DIFF} -gt 2592000 ]; then
		gpg --keyserver keys.openpgp.org --refresh-keys DBA36B5181D0C816F630E889D980A17457F6FB06
		gpg --tofu-policy good DBA36B5181D0C816F630E889D980A17457F6FB06
		touch "${HOME}/.config/Signal/gpg.refresh"
	fi
else
	mkdir -p "${HOME}/.config/Signal"
	touch "${HOME}/.config/Signal/gpg.refresh"
fi

# Trust on first use
if gpg --trust-model tofu --verify InRelease; then
	echo "### ${DIST}/InRelease signature verified."
	SHA256=$(grep -A5 ^SHA256 InRelease | awk '/main\/binary-amd64\/Packages.xz/ {print $1}')
else
	_die "### ${DIST}/InRelease signature FAILED."
fi

# Download & verify Packages.xz
if curl -sLO "${BASEURL}/${DIST}/main/binary-amd64/Packages.xz"; then
	echo "### Download ${DIST}/main/binary-amd64/Packages.xz OK."
else
	_die "### Download Packages.xz FAILED."
fi

if sha256sum Packages.xz | grep -q "${SHA256}"; then
	echo "### Packages.xz checksum verified."
else
	_die "### Packages.xz checksum FAILED."
fi

sudo mkdir -p ${DEST}
if [ ! -f ${DEST}/.version.txt ]; then
	echo "### Signal does not appear to be installed yet."
	echo "0" | sudo tee ${DEST}/.version.txt
fi

CURRENT=$(cat ${DEST}/.version.txt)
echo "### Available versions:"
 VERSION=$(xz -dc Packages.xz | grep -E '^Version' | sort -k2 -V | tail | fzf --no-clear --height=50% --prompt "${CURRENT}> ")
FILENAME=$(xz -dc Packages.xz | grep -E -A10 "^${VERSION}$" | awk '/^Filename/ {print $2}')
  SHA256=$(xz -dc Packages.xz | grep -E -A10 "^${VERSION}$" | awk '/^SHA256/   {print $2}')

echo
echo "### Downloading ${FILENAME}..."
if ${DEBUG} curl -LO "${BASEURL}/${FILENAME}"; then
	echo "### ${FILENAME} downloaded."
else
	_die "Failed to download package"
fi

if sha256sum signal-desktop*amd64.deb | grep --color "${SHA256}"; then
	echo "### ${FILENAME} checksum verified."
else
	_die "### ${FILENAME} checksum FAILED."
fi

# Extract the data part of the Debian package 
if ${DEBUG} ar x signal-desktop*amd64.deb data.tar.xz; then
	echo "### data.tar.xz extraction OK."
else
	_die "### data.tar.xz extraction FAILED."
fi

# Install
if [ -d ${DEST}.old ]; then
	echo "### Removing ${DEST}.old"
	${DEBUG} sudo rm -r ${DEST}.old
fi

echo "### Move ${DEST} to ${DEST}.old"
${DEBUG} sudo mv -v ${DEST} ${DEST}.old

echo "### Extracting data.tar.xz to /opt"
${DEBUG} sudo tar -C /                                   -xJf data.tar.xz ./opt

echo "### Extracting icons to /usr/share/icons"
${DEBUG} sudo tar -C / --transform="s|usr|$HOME/.local|" -xJf data.tar.xz ./usr/share/icons/

echo "### Change ownership to root:root"
${DEBUG} sudo chown -R root:root ${DEST}*

echo "### Create /usr/local/bin/signal-desktop symlink"
${DEBUG} sudo ln -svf ${DEST}/signal-desktop /usr/local/bin/signal-desktop

echo "Currently installed: ${VERSION}" | ${DEBUG} sudo tee ${DEST}/.version.txt