[enh] Add update.sh script to ease the app version update

update.sh

@@ -0,0 +1,55 @@
+#!/bin/bash
+
+set -eu
+
+# check usage
+if [[ $# -ne 1 ]]; then
+  cat << EOF
+Usage: `basename $0` version
+Update the application version shipped by this package.
+EOF
+  exit 1
+fi
+
+version=$1
+
+# -- helper:
+# check that the version is set in a given file.
+check_version() {
+  grep -q "$version" "$1" \
+    && echo "[OK]" \
+    || echo "[ERROR]"
+}
+
+# set new version
+echo ":: set new version: ${version}"
+
+echo -n "- processing 'scripts/_common.sh'... "
+sed -ri "s#^(VERSION=).*#\1\"${version}\"#" \
+    ./scripts/_common.sh
+check_version "./scripts/_common.sh"
+
+echo -n "- processing 'manifest.json'... "
+sed -ri "s#(\"version\":).*#\1 \"${version}\",#" \
+    manifest.json
+check_version "./manifest.json"
+
+echo -n "- processing 'README.md'... "
+sed -ri "s#(\*\*Shipped version:\*\*).*#\1 ${version}#" \
+    README.md
+check_version "./README.md"
+
+source ./scripts/_common.sh
+
+# download and calculate the checksum
+echo ":: downloading source tarball..."
+rm -f "source.tar.gz"
+wget -O "source.tar.gz" "$WALLABAG_SOURCE_URL"
+calc_sum=$(sha256sum "source.tar.gz" | awk '{print $1}')
+
+# set new checksum
+echo ":: set new checksum: ${calc_sum}"
+sed -ri "s#^(WALLABAG_SOURCE_SHA256=).*#\1\"${calc_sum}\"#" \
+    ./scripts/_common.sh
+
+echo "DONE!"