Merge pull request #16701 from vitorgalvao/find_sparkle_appcast

developer scripts: add find_sparkle_appcast

developer/bin/find_sparkle_appcast

@@ -0,0 +1,77 @@
+#!/bin/bash
+#
+# find_sparkle_appcast
+#
+
+###
+### functions
+###
+
+usage() {
+  local program exit_status
+
+  program="$(basename "$0")"
+  exit_status="$1"
+
+  echo "usage: ${program} <path_to_app>"
+  exit "${exit_status}"
+}
+
+absolute_path() {
+  echo "$(cd "$(dirname "$1")" && pwd)/$(basename "$1")"
+}
+
+appcast_found_error() {
+  local error_reason="$1"
+
+  echo "An appcast was found, but it ${error_reason}. You should:
+
+  1. Check your internet connection.
+  2. Try again later.
+  3. Contact the developer."
+
+  exit 1
+}
+
+###
+### main
+###
+
+# exit if no argument (or more than one) was given
+if [[ -z "$1" ]] || [[ -n "$2" ]]; then
+  usage 1
+fi
+
+# get plist
+path_to_app="$(absolute_path "$1")"
+path_to_plist="${path_to_app}/Contents/Info.plist"
+
+if [[ ! -f "${path_to_plist}" ]]; then
+  echo 'You need to use this on a .app bundle. Please verify your target.'
+  usage 1
+fi
+
+# get appcast
+appcast_url="$(defaults read "${path_to_plist}" 'SUFeedURL' 2>/dev/null)"
+
+if [[ -z "${appcast_url}" ]]; then
+  echo 'It appears this app does not have a Sparkle appcast.'
+  exit 0
+fi
+
+# vaidate appcast
+appcast_http_response="$(curl --silent --head --write-out '%{http_code}' "${appcast_url}" -o /dev/null)"
+[[ "${appcast_http_response}" != '200' ]] && appcast_found_error 'returned a non-200 (OK) HTTP response code.'
+
+appcast_sha=$(curl --silent "${appcast_url}" | shasum --algorithm 256 | awk '{ print $1 }')
+[[ "${appcast_sha}" == 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855' ]] && appcast_found_error 'seems to be empty'
+
+# output appcast
+echo "A Sparkle appcast was found. You sould add it to your cask as
+
+appcast '${appcast_url}',
+        :sha256 => '${appcast_sha}'
+
+You should likely also add 'auto_updates true'"
+
+exit 0