#!/bin/bash
#
# Distributed perftest.
# Runs perftest clients on multiple hosts using ssh.
# 

set -e
usage() {
cat <<EOF
usage: $0 <perftest-args> -- <client-hosts ...> [ --- <broker hosts...> ]
Client & broker hosts can also be set in env vars CLIENTS and BROKERS.

Run perftest with clients running on the clients and brokers running
on the specified hosts. Clients are assigned to client hosts round
robin: publishers first, then subscribers. If there are multiple
brokers (for cluster tests) clients connect to them round robin.

Broker hosts can be listed with -b in perftest-args or after ---
at the end of the arguments.

Error: $*
EOF
exit 1
}

TESTDIR=${TESTDIR:-$PWD}	# Absolute path to test exes on all hosts.

collect() { eval $COLLECT=\""\$$COLLECT $*"\"; }
NPUBS=1
NSUBS=1
COLLECT=ARGS
while test $# -gt 0; do
    case $1 in
	--publish|--subscribe|--setup|--control) usage "Don't pass perftest action flags: $1" ;;
	--npubs) collect $1 $2; NPUBS=$2; shift 2 ;;
	--nsubs) collect $1 $2; NSUBS=$2; shift 2 ;;
	-s|--summary) collect $1; QUIET=yes; shift 1 ;;
	-b|--broker) BROKERS="$BROKERS $2"; shift 2;;
	--) COLLECT=CLIENTARG; shift ;;
	---) COLLECT=BROKERARG; shift;;
	*) collect $1; shift ;;
    esac
done

CLIENTS=${CLIENTARG:-$CLIENTS}
if [ -z "$CLIENTS" ]; then usage "No client hosts listed after --"; fi
BROKERS=${BROKERARG:-$BROKERS}
if [ -z "$BROKERS" ]; then usage "No brokers specified"; fi

PERFTEST="$TESTDIR/perftest $ARGS"

CLIENTS=($CLIENTS)
BROKERS=($BROKERS)
start() {
    CLIENT=${CLIENTS[i % ${#CLIENTS[*]}]}
    BROKER=${BROKERS[i % ${#BROKERS[*]}]}
    ARGS="$* --broker $BROKER"
    cmd="ssh -n $CLIENT $PERFTEST $ARGS"
    test -z "$QUIET" && echo "Client $i: $cmd"
    $cmd &
}

$PERFTEST --setup -b ${BROKERS[0]}
for (( i=0 ; i < $NPUBS ; ++i)); do start --publish; done
for (( ; i < $NPUBS+$NSUBS ; ++i)); do start --subscribe; done
$PERFTEST --control  -b ${BROKERS[0]}