From 9e7ca7538e2f96fda9cbdc126887afc8d7d15b11 Mon Sep 17 00:00:00 2001
From: Jonas Gunz <himself@jonasgunz.de>
Date: Sun, 7 Jun 2020 20:59:48 +0200
Subject: Added parallel task execution

Parallel task execution + hostname and stderr prefix to output
---
 ltask          | 42 +++++++++++++++++++++++++++++++-----------
 tasks/example  |  5 ++++-
 tools/rexec.sh |  2 +-
 3 files changed, 36 insertions(+), 13 deletions(-)

diff --git a/ltask b/ltask
index 306e972..ee4829b 100755
--- a/ltask
+++ b/ltask
@@ -36,6 +36,8 @@ export readonly INCLUDE_DIR=$BASEDIR/libs
 TASK=
 TARGET=
 
+PARALLEL="false"
+
 HOSTS=()
 FILES=()
 INCLUDES=()
@@ -61,6 +63,8 @@ function parse_args() {
 			-H)
 				i=$((i+1))
 				HOSTS+=(${ARGV[$i]});;
+			-p)
+				PARALLEL="true";;
 			-h)
 				print_help 0;;
 			*)
@@ -79,6 +83,7 @@ Options:
 	-H HOST		Add HOST to target hosts. can be used
 			to target single hosts without defining
 			a custom target
+	-p		Force parallel execution
 	-h		print this help text
 EOF
 	exit $1
@@ -97,8 +102,8 @@ fi
 
 unset TASK_ISSET
 
-[ -f $TASK_DIR/$TASK ] && source $TASK_DIR/$TASK
 [ -f $TARGET_DIR/$TARGET ] && source $TARGET_DIR/$TARGET
+[ -f $TASK_DIR/$TASK ] && source $TASK_DIR/$TASK
 
 if [ -z $TASK_ISSET ]; then
 	perror Task did not load correctly
@@ -110,6 +115,9 @@ HOSTS_UNIQUE=($(tr ' ' '\n' <<< "${HOSTS[@]}" | sort -u))
 COUNTER=0
 HOSTCOUNT=${#HOSTS_UNIQUE[@]}
 
+[ $PARALLEL = "true" ] && AND="&"
+declare -A HOST_PID
+
 for hoststring in "${HOSTS_UNIQUE[@]}"; do
 	rexecargs=""
 	IFS=$':' read hostname port <<< "$hoststring"
@@ -121,20 +129,32 @@ for hoststring in "${HOSTS_UNIQUE[@]}"; do
 
 	rexecargs+="$hostname ${INCLUDES[@]} $TASK_DIR/$TASK"
 
-	echo
-	echo "<=== $hostname ===>"
-	echo
-	$TOOL_DIR/rexec.sh $rexecargs
-	[ $? -ne 0 ] && FAILED_HOSTS+=($hostname)
-
-	COUNTER=$(($COUNTER + 1))
-	PERCENT=$(($COUNTER * 100 / $HOSTCOUNT))
-	perror -n "\r[$COUNTER: $PERCENT%] "
+	set -o pipefail
+	eval "$TOOL_DIR/rexec.sh $rexecargs | (while read l; do echo [$hostname] \$l; done) $AND"
+	RET=$?
+
+	if [ $PARALLEL = "true" ]; then
+		HOST_PID[$hostname]=$!
+	else
+		[ $RET -ne 0 ] && FAILED_HOSTS+=($hostname)
+		COUNTER=$(($COUNTER + 1))
+		PERCENT=$(($COUNTER * 100 / $HOSTCOUNT))
+		perror -n "\r[$COUNTER: $PERCENT%] "
+	fi
 done
 
+if [ $PARALLEL = "true" ]; then
+	perror Waiting for remote tasks to finish...
+	for hostname in ${!HOST_PID[@]}; do
+		wait ${HOST_PID[$hostname]}
+		[ $? -ne 0 ] && FAILED_HOSTS+=($hostname)
+	done
+	perror Done!
+fi
+
 if [ ${#FAILED_HOSTS[@]} -gt 0 ]; then
 	perror "\n"
-	perror ${#FAILED_HOSTS[@]} hosts failed the task:
+	perror ${#FAILED_HOSTS[@]} targets failed:
 	perror ${FAILED_HOSTS[@]}
 	exit 1
 fi
diff --git a/tasks/example b/tasks/example
index bc78361..deb3c94 100644
--- a/tasks/example
+++ b/tasks/example
@@ -3,7 +3,7 @@
 function task_exec() {
 	whoami
 	hostname
-	uptime
+	uptime 1>&2
 }
 
 function task_setup() {
@@ -12,6 +12,9 @@ function task_setup() {
 	# $TOOL_DIR
 	# $INCLUDE_DIR
 
+	# Available Configuration
+	# $PARALLEL "true"/"false"
+
 	INCLUDES+=()
 
 	SSH_USER=server
diff --git a/tools/rexec.sh b/tools/rexec.sh
index 388cbc3..d60c021 100755
--- a/tools/rexec.sh
+++ b/tools/rexec.sh
@@ -86,5 +86,5 @@ parse_args
 
 [ ${#FILES[@]} -gt 0 ] && scp $SSH_OPTIONS -i $SSH_IDENTITY -P $SSH_PORT ${FILES[@]} $SSH_HOST:
 
-cat ${SCRIPT_FILES[@]} | $SSH -p $SSH_PORT -i $SSH_IDENTITY $SSH_HOST "/bin/bash 2>&1" 2>/dev/null
+cat ${SCRIPT_FILES[@]} | $SSH -p $SSH_PORT -i $SSH_IDENTITY $SSH_HOST '/bin/bash 2> >(while read line; do echo [ERR] $line; done)' 2>/dev/null
 exit $?
-- 
cgit v1.2.3