download-atom-release.sh

#!/bin/bash

set -e

SELECTOR='string(//*[local-name()="entry"]/*[local-name()="title"][not(contains(text(), "beta"))])'
INSTALLED="dpkg-query -W -f '\${Version}' atom"
ARTIFACT='atom-amd64.deb'
INSTALL='sudo dpkg --skip-same-version --install'

version=$(
  curl --silent https://github.com/atom/atom/tags.atom |
    xmllint --xpath "$SELECTOR" -
)

test -z "$version" && {
  echo "Latest version not found" >&2
  exit 1
}

installed=$( eval "$INSTALLED" )

test "$version" = "$installed" && {
  echo "Version $version already installed"
  exit
}

url="https://github.com/atom/atom/releases/download/v$version/$ARTIFACT"
file=$( mktemp --tmpdir atomXXXX.deb )
cmd="$INSTALL $file"

echo "Downloading $url to $file ..."
curl -L -o "$file" "$url"

echo "Running install: $cmd"
eval "$cmd"

echo "Removing temporary file: $file"
rm -f "$file"