Allow parallel time check

Adds an onptional ability to run each mirror test in parallel. This
could possibly produce inaccurate results but speeds up the process for
a number of mirrors.
Thiw uses GNU parallel for parallel checks.

Signed-off-by: Dmitry Kuzmenko <dmitry.kuzmenko@dsr-corporation.com>

1 files changed, 41 insertions, 13 deletions

diff --git a/src/rankmirrors.sh.in b/src/rankmirrors.sh.in
index 9f728ee..fe4b885 100644
--- a/src/rankmirrors.sh.in
+++ b/src/rankmirrors.sh.in
@@ -42,6 +42,7 @@ usage() {
 	echo "  -u, --url           test a specific URL"
 	echo "  -v, --verbose       be verbose in output"
 	echo "  -r, --repo          specify a repository name instead of guessing"
+	echo "  -p, --parallel      run tests in parallel for all servers (may be inaccurate, depends on GNU parallel)"
 	exit 0
 }
 
@@ -98,6 +99,11 @@ getfetchurl() {
 
 # This exists to remove the need for a separate interrupt function
 finaloutput() {
+	local -a timesarray=()
+	if [[ -f "$tmpfile" ]]; then
+		readarray -t timesarray <$tmpfile
+		rm $tmpfile
+	fi
 	IFS=$'\n' read -r -d '' -a sortedarray < \
 		<(printf '%s\n' "${timesarray[@]}" | LC_COLLATE=C sort)
 
@@ -144,6 +150,7 @@ while [[ $1 ]]; do
 				[[ $2 ]] || err "Must specify repository name.";
 				TARGETREPO="$2";
 				shift 2;;
+			parallel) PARALLEL=1 ; shift ;;
 			*) err "'$1' is an invalid argument."
 		esac
 	elif [[ ${1:0:1} = - ]]; then
@@ -177,6 +184,7 @@ while [[ $1 ]]; do
 						[[ $2 ]] || err "Must specify number.";
 						NUM="$2";
 						snum=2;;
+					p) PARALLEL=1 ;;
 					*) err "'$1' is an invalid argument." ;;
 				esac
 			done
@@ -197,6 +205,7 @@ done
 [[ $MAX_TIME ]] || MAX_TIME=10
 [[ $FILE && $CHECKURL ]] && err "Cannot specify a URL and mirrorfile."
 [[ $FILE || $CHECKURL || $STDIN ]] || err "Must specify URL, mirrorfile, or stdin."
+[[ $PARALLEL ]] && ! command -v parallel >/dev/null 2>&1 && err "GNU parallel is not installed."
 
 # Single URL handling
 if [[ $CHECKURL ]]; then
@@ -215,7 +224,30 @@ elif [[ $FILE ]]; then
 	echo "# Server list generated by rankmirrors on $(date +%Y-%m-%d)"
 fi
 
-timesarray=()
+get_url_time() {
+	server=$1
+	url="$(getfetchurl "$server")"
+	[[ $url = fail ]] && err "URL '$server' is malformed."
+	time=$(gettime "$url")
+	echo "$time $server" >>$tmpfile
+
+	# Output
+	if [[ $VERBOSE && $TIMESONLY ]]; then
+		echo "$server ... $time"
+	elif [[ $VERBOSE ]]; then
+		echo "# $server ... $time"
+	elif [[ $TIMESONLY ]]; then
+		echo -n "   *"
+	fi
+}
+
+tmpfile=$(mktemp)
+if [[ $PARALLEL ]]; then
+	servers=()
+	# Exports for GNU parallel
+	export MAX_TIME ARCH TARGETREPO VERBOSE TIMESONLY tmpfile
+	export -f getfetchurl gettime get_url_time
+fi
 for line in "${linearray[@]}"; do
 	if [[ $line =~ ^[[:space:]]*# ]]; then
 		[[ $TIMESONLY ]] || echo $line
@@ -224,19 +256,15 @@ for line in "${linearray[@]}"; do
 		# Getting values and times and such
 		server="${line#*= }"
 		server="${server%%#*}"
-		url="$(getfetchurl "$server")"
-		[[ $url = fail ]] && err "URL '$URL' is malformed."
-		time=$(gettime "$url")
-		timesarray+=("$time $server")
-
-		# Output
-		if [[ $VERBOSE && $TIMESONLY ]]; then
-			echo "$server ... $time"
-		elif [[ $VERBOSE ]]; then
-			echo "# $server ... $time"
-		elif [[ $TIMESONLY ]]; then
-			echo -n "   *"
+
+		if [[ $PARALLEL ]]; then
+			servers+=($server)
+		else
+			get_url_time $server
 		fi
 	fi
 done
+if [[ $PARALLEL ]]; then
+	parallel get_url_time ::: "${servers[@]}"
+fi
 finaloutput