run-stat-flowd-tuple

#
#  Synopsis:
#	Generate a tuple of stats in schema/$1/run/flowd.{pid,gyr}
#  Description:
#	For flowd, the stats sum the columns in the *.fdr records.
#
#	<green>	is the sum of all *.fdr records with both processes and
#	queries in an OK state.  <yellow> is currently 0 and <red> is the
#	sum of flows with at least 1 query of process not OK.
#
#	See the particular etc/*.flow file for what is OK or not OK.
#
#		State
#		OK		flowd verified running
#		OFFL		flowd offline, run/*.{pid,gyr} empty
#		YETI		flowd seems to exist but not seen by pgrep
#		ZOMBI		flowd online run/*.{pid,gyr} not empty
#  Usage:
#	sbin/run-stat-flowd-tuple flowd 
#	sbin/run-stat-flowd-tuple flowd>wework
#  Exit Status:
#	0	gyr tuple written
#	1	unexpected error, no tuple written
#  Note:
#	Despartley need to need simplify and unifiy with similar script in
#	blobio/sbin/run-stat-flowd-tuple!
#

STALE_AFTER=61		#  need to derive heartbeat values in etc/<schema>.flow

die()
{
	echo "$(basename $0): ERROR: $@" >&2
	exit 1
}

test $# = 1 || die "wrong number of arguments: got $#, expected 1"
SCHEMA=$1	#  process name (flowd or flowd>tag)
test -n "$SETSPACE_ROOT" || die "env not defined: SETSPACE_ROOT"
cd $SETSPACE_ROOT || die "cd SETSPACE_ROOT failed: exit status=$?"

SCHEMA_DIR=schema/$SCHEMA
test -d $SCHEMA_DIR || die "no schema dir: $SCHEMA_DIR"
cd $SCHEMA_DIR || die "cd schema dir ($SCHEMA_DIR) failed: exit status=$?"

FLOW_PATH=etc/$SCHEMA.flow	#  path to <schema>/etc/<schema>.flow file

PID_PATH=run/flowd.pid		#  path to $RUN_PATH/flowd.pid
PID_MTIME=null			#  most recent write to $RUN_PATH/flowd.pid

BOOT_EPOCH=null			#  tail -1 $RUN_PATH/flowd.pid
				#  can be overriden by value in "run/flowd.gyr"
BOOT_GYR='null	null	null'

RECENT_EPOCH=null		#  epoch of most recent GYR sample
RECENT_GYR='null	null	null'

GYR_PATH=run/flowd.gyr

#
#  The service is enabled if etc/<schema>.flow exists. The state
#  (UP,DOWN,ZOMBI,YETI) of the flowd process is determined by the
#  existence, values in, or modify time of the files run/flowd.{pid,gyr}.
#
if [ -e $FLOW_PATH ]; then
	if [ -e $PID_PATH ];  then
		if [ -s $PID_PATH ];  then
			if file-stale-mtime $STALE_AFTER $PID_PATH;  then
				_P=$(pgrep -F $PID_PATH >/dev/null)
				STATUS=$?
				case $STATUS in
				0)
					STATE=YETI
					;;
				1)
					#  pgrep grumbles about a syntax error
					#  in pidfile, yet still exits with
					#  status 1.
					test -n "$_P"			&&
						die "pgrep failed: $_P"
					STATE=ZOMBI
					;;
				*)
					die "pgrep failed: exit status=$STATUS"\
						"$_P"
					;;
				esac
			else
				STATE=UP
			fi
		else
			STATE=ZOMBI		#  empty pid file
		fi
	else
		STATE=DOWN
		if [ -e $GYR_PATH ];  then	#  exit did not zap flowd.gyr
			STATE=ZOMBI
		fi
	fi
else
	STATE=OFFL
	if [ -e $PID_PATH -o -e $GYR_PATH ];  then
		STATE=ZOMBI
	fi
fi

if [ -e $PID_PATH ];  then
	if [ -s $PID_PATH ];  then
		BOOT_EPOCH=$(tail -1 $PID_PATH)
	fi
fi

#  is -s test redundant with above -s test?
if [ -s $PID_PATH ];  then
	PID_MTIME=$(file-stat-mtime $PID_PATH)
	BOOT_EPOCH=$(tail -1 $PID_PATH)
fi

if [ -e $GYR_PATH ];  then
	if [ -s $GYR_PATH ];  then
		BOOT_EPOCH=$(grep '^boot	' $GYR_PATH | cut -f2)
		BOOT_GYR=$(grep '^boot	' $GYR_PATH | cut -f3-5)
		RECENT_EPOCH=$(grep '^recent	' $GYR_PATH | cut -f2)
		RECENT_GYR=$(grep '^recent	' $GYR_PATH | cut -f3-5)
	elif [ $STATE = UP ];  then
		STATE=YETI
	fi
elif [ $STATE = UP ];  then
	STATE=YETI
fi

cat <<END
$SCHEMA	$STATE	$BOOT_EPOCH	$BOOT_GYR	$RECENT_EPOCH	$RECENT_GYR
END