Add timeout to systemd script, stop child units and document absolute and relative folder names

.gitignore

@@ -25,3 +25,7 @@ debian/.debhelper
 obj-x86_64-linux-gnu/
 
 .idea
+
+systemd/grive-timer\@.service
+
+systemd/grive-changes\@.service

README.md

@@ -80,22 +80,32 @@ Google Drive clients on other platforms (it misses the almost instantious
 download of changed files in the google drive).
 
 Grive installs such a basic solution which uses inotify-tools together with
-systemd timer and services. You can enable it for a folder in your `$HOME`
-directory (in this case the `$HOME/google-drive`):
+systemd timer and services. You can enable it for a directory. The name can
+either be an absolute path or one relative to `${HOME}`. Let's use
+`${HOME}/google-drive` (so relative: `google-drive`):
 
 First install the `inotify-tools` (seems to be named like that in all major distros): 
 test that it works by calling `inotifywait -h`.
 
-Prepare a Google Drive folder in your $HOME directory with `grive -a`.
+Prepare a Google Drive folder in your `${HOME}` directory with:
 
 ```bash
-# 'google-drive' is the name of your Google Drive folder in your $HOME directory
+mkdir -p ${HOME}/google-drive
+cd ${HOME}/google-drive
+grive -a
+```
+
+Afterwards, the scheduled sync can be enabled via:
+
+```bash
+# 'google-drive' is in this case the relative name of your Google Drive folder
+# in your ${HOME} directory
 systemctl --user enable grive@$(systemd-escape google-drive).service
 systemctl --user start grive@$(systemd-escape google-drive).service
 ```
 
-You can enable and start this unit for multiple folders in your `$HOME`
-directory if you need to sync with multiple google accounts.
+You can enable and start this unit for multiple folders if you need to sync
+with multiple google accounts.
 
 You can also only enable the time based syncing or the changes based syncing
 by only directly enabling and starting the corresponding unit:

systemd/grive-sync.sh

@@ -1,24 +1,42 @@
 #!/bin/bash
 
 # Copyright (C) 2009 Przemyslaw Pawelczyk <[email protected]>
-#           (C) 2017 Jan Schulz <[email protected]>             
+#           (C) 2017 Jan Katins <[email protected]>
 ##
 ## This script is licensed under the terms of the MIT license.
 ## https://opensource.org/licenses/MIT
 
 # Fail on all errors
 set -o pipefail
 
+abort() {
+    echo >&2 "${*}";
+    exit 1;
+}
+
+check_command(){
+    type ${1} >/dev/null 2>&1 || abort "I require '${1}' command but it's not available. Aborting."
+}
+
 # We always start in the current users home directory so that names always start there
-cd ~
+cd ${HOME} || abort "Cannot switch to HOME dir: ${HOME}"
 
+check_command flock
+check_command timeout
+check_command inotifywait
+check_command ping
 
 ### ARGUMENT PARSING ###
 SCRIPT="${0}"
-DIRECTORY=$(systemd-escape --unescape -- "$2")
+DIRECTORY=$(systemd-escape --unescape -- "${2}")
+
+# Defaults:
+# let grive run for 20min and then abort, assuming that it hangs. This might be wrong for big syncs,
+# but we will restart...
+GRIVE_TIMEOUT="${GRIVE_TIMEOUT:-20m}"
 
-if [[ -z "$DIRECTORY" ]] || [[ ! -d "$DIRECTORY" ]] ; then
-	echo "Need a directory name in the current users home directory as second argument. Aborting."
+if [[ -z "${DIRECTORY}" ]] || [[ ! -d "${DIRECTORY}" ]] ; then
+	echo "Need a directory name (absolute or relative to the current users home directory) as second argument. Got ${DIRECTORY}. Aborting."
 	exit 1
 fi
 
@@ -39,7 +57,7 @@ fi
 
 
 ### LOCKFILE BOILERPLATE ###
-LOCKFILE="/run/user/"$(id -u)"/"$(basename "$0")"_"${DIRECTORY//\//_}""
+LOCKFILE="/run/user/$(id -u)/$(basename "$0")_${DIRECTORY//\//_}"
 LOCKFD=99
 
 # PRIVATE
@@ -57,13 +75,13 @@ shlock()            { _lock s; }   # obtain a shared lock
 unlock()            { _lock u; }   # drop a lock
 
 ### SYNC SCRIPT ###
-# Idea: only let one script run, but if the sync script is called a second time 
+# Idea: only let one script run, but if the sync script is called a second time
 # make sure we sync a second time, too
 
 sync_directory() {
 	_directory="${1}"
 
-	reset_timer_and_exit() { echo "Retriggered google drive sync ('${_directory}')" && touch -m $LOCKFILE && exit; }
+	reset_timer_and_exit() { echo "Retriggered google drive sync ('${_directory}')" && touch -m "${LOCKFILE}" && exit; }
 
 	exlock_now || reset_timer_and_exit
 
@@ -79,11 +97,12 @@ sync_directory() {
 	TIME_AT_START=0
 	TIME_AT_END=1
 	while [[ "${TIME_AT_START}" -lt "${TIME_AT_END}" ]]; do
-	    echo "Syncing '${_directory}'..." 
-	    TIME_AT_START="$(stat -c %Y "$LOCKFILE")"
-	    grive -p "${_directory}" 2>&1 | grep -v -E "^Reading local directories$|^Reading remote server file list$|^Synchronizing files$|^Finished!$"
-	    TIME_AT_END="$(stat -c %Y "$LOCKFILE")"
-	    echo "Sync of '${_directory}' done." 
+	    echo "Syncing '${_directory}'..."
+	    TIME_AT_START="$(stat -c %Y "${LOCKFILE}")"
+	    # brace group: only error in case grive fails or hung, not because grep filtered out everything when nothing needed to be synced...
+	    timeout "${GRIVE_TIMEOUT}" grive -p "${_directory}" 2>&1 | { grep -v -E "^Reading local directories$|^Reading remote server file list$|^Synchronizing files$|^Finished!$" || true ; }
+	    TIME_AT_END="$(stat -c %Y "${LOCKFILE}")"
+	    echo "Sync of '${_directory}' done."
 	done
 
 	# always exit ok, so that we never go into a wrong systemd state
@@ -97,15 +116,13 @@ sync_directory() {
 listen_directory() {
 	_directory="${1}"
 
-	type inotifywait >/dev/null 2>&1 || { echo >&2 "I require inotifywait but it's not installed. Aborting."; exit 1; }
-
 	echo "Listening for changes in '${_directory}'"
 
 	while true #run indefinitely
-	do 
+	do
 		# Use a different call to not need to change exit into return
-		inotifywait -q -r -e modify,attrib,close_write,move,create,delete --exclude ".grive_state|.grive" "${_directory}" > /dev/null 2>&1 && ${SCRIPT} sync $(systemd-escape "${_directory}")
-		#echo ${SCRIPT} "${_directory}"
+		# Ignore errors
+		inotifywait -q -r -e modify,attrib,close_write,move,create,delete --exclude ".grive_state|.grive" "${_directory}" > /dev/null 2>&1 && ${SCRIPT} sync "$(systemd-escape "${_directory}")" || continue
 	done
 
 	# always exit ok, so that we never go into a wrong systemd state

systemd/grive@.service

@@ -1,6 +1,7 @@
 [Unit]
 Description=Google drive sync (main)
 Requires=grive-timer@%i.timer grive-changes@%i.service
+PropagatesStopTo=grive-timer@%i.timer grive-changes@%i.service
 
 # dummy service
 [Service]