#!/bin/bash
set -e -o pipefail
if [ $# -lt 2 ]; then
  cat 1>&2 <<EOF
Usage: $0 SSname cmd [-x] [-np n] [-f file] [...args]
Where name is the name of a VM scale set.

Runs cmd on every machine in a scale set,
 passing args and, 
  if -f, one line from file per worker
  unless -x, worker id
 by doing as it were
  [ echo line-from-file |] ssh machine "$cmd [id] "$args"" 
EOF
  exit 1
fi
group=cc
name=$1
cmd="$2"
shift 2
if [ "$1" = "-x" ]
then
 id=-x
 shift
else
 id=
fi
if [ "$1" = "-np" ]
then
 np=$2
 shift
 shift
else
 np=$(az vmss get-instance-view -g $group -n $name | jq '.virtualMachine.statusesSummary | .[0].count')
fi
echo "|$name|$cmd|$@|$np|" 1>&2
me=$(az vm list-ip-addresses -g cc -n Deb1 | jq -r '.[0].virtualMachine.network.publicIpAddresses|.[0].ipAddress')
echo me=$me 1>&2
if [ "$1" = "-f" ]
then
 file=$2
 shift 2
 tfile=$(mktemp)
 split -n r/$np -u --filter="cat > $tfile\$\$" $file &
 # Wait for fifos to be built
 while [ $np -gt $(ls ${tfile}* | wc -l) ]; do echo -n . 1>&2; sleep 1; done
 echo 1>&2
 wc -l ${tfile}* 1>&2
else
 file=/dev/null
fi
echo "|$np|$file|$tfile|" 1>&2
paste -d ' ' \
 <(if [ "$file" = "/dev/null" ]
   then yes /dev/null|head -$np
   else
     echo ${tfile}?* | tr ' ' '\012' # the name of the file of
                                    # input lines for each worker
   fi
  ) \
 <(az vmss list-instance-connection-info -g $group -n $name | tr -s ',": ' '\t' | \
    tail -n +2 | head -$np |cut -f 3-5 | \
  while read i ip port
   do
    echo $i $port $ip
   done) | \
 parallel --gnu --colsep ' ' -j $np "$(dirname "$0")"/internal/invoke.sh $id $me "$cmd" {} "$@" || { r=$? ; echo parallel exited with status=$r 1>&2;}
if [ "${tfile}" ]; then rm ${tfile}*; fi