jlogsdon · January 27, 2016 08:15
diff --git a/aws-tail.sh b/aws-tail.sh
 #!/usr/bin/env bash
 # Usage: aws-tail [options] <tag-value> <file>
 #
 # Tail the same file on servers tagged with the given tag value. Each line is prefixed with the string "[$HOST_IP]"
 # where $HOST_IP is the IP address the line came from. This file can be optionally filtered on the remote end to reduce
 # transit data.
 #
 # Note that this is not perfect: output is not synchronized across connections which can lead to one line bleeding into
 # another. For a general idea of what's going on, however, it works fantastic.
 #
 # Options:
 #   -c number of servers to listen in on. This defaults to 200 which is kind of insane if you aren't filtering.
 #   -f accepts a scalar filter value. Tags in relevant logs are great (such as RUBICON) for this.
 #   -u is for specifying the username to connect with (defaults to `whoami`).
 #
 # Example:
 #
 #   Follow production logs for the Offers facet and grep for RUBICON on the server side.
 #
 #     aws-tail -f RUBICON -u james.logsdon tapjoyserver-web_offers /mnt/log/tapjoyserver/production.log

 username=`whoami`
 count=200 # A crazy maximum really

 while getopts 'c:f:i:u:' opt; do
  case $opt in
    c) count=$OPTARG ;;
    f) filter=$OPTARG ;;
    i) identity=$OPTARG ;;
    u) username=$OPTARG ;;
  esac
 done
 shift $(($OPTIND - 1)) # Remove the parsed arguments

 search=$1
 file=$2

 hosts=$(aws ec2 describe-instances --filters "Name=tag-value,Values=${search}" | \
  jq -c -M -r '.Reservations[].Instances[].PublicIpAddress' | \
  grep -v '^null' | \
  head -n${count})

 command="tail -F ${file}"
 if [ ! -z $filter ]; then
  command+=" | grep '${filter}'"
 fi

 trap handle_int INT
 function handle_int() {
  for pid in $(jobs -p)
  do
    kill $pid
  done
 }

 for host in $hosts
 do
  ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no ${username}@${host} "${command}" &
 done

 wait
	#!/usr/bin/env bash
	# Usage: aws-tail [options] <tag-value> <file>
	#
	# Tail the same file on servers tagged with the given tag value. Each line is prefixed with the string "[$HOST_IP]"
	# where $HOST_IP is the IP address the line came from. This file can be optionally filtered on the remote end to reduce
	# transit data.
	#
	# Note that this is not perfect: output is not synchronized across connections which can lead to one line bleeding into
	# another. For a general idea of what's going on, however, it works fantastic.
	#
	# Options:
	# -c number of servers to listen in on. This defaults to 200 which is kind of insane if you aren't filtering.
	# -f accepts a scalar filter value. Tags in relevant logs are great (such as RUBICON) for this.
	# -u is for specifying the username to connect with (defaults to `whoami`).
	#
	# Example:
	#
	# Follow production logs for the Offers facet and grep for RUBICON on the server side.
	#
	# aws-tail -f RUBICON -u james.logsdon tapjoyserver-web_offers /mnt/log/tapjoyserver/production.log

	username=`whoami`
	count=200 # A crazy maximum really

	while getopts 'c:f:i:u:' opt; do
	case $opt in
	c) count=$OPTARG ;;
	f) filter=$OPTARG ;;
	i) identity=$OPTARG ;;
	u) username=$OPTARG ;;
	esac
	done
	shift $(($OPTIND - 1)) # Remove the parsed arguments

	search=$1
	file=$2

	hosts=$(aws ec2 describe-instances --filters "Name=tag-value,Values=${search}" \| \
	jq -c -M -r '.Reservations[].Instances[].PublicIpAddress' \| \
	grep -v '^null' \| \
	head -n${count})

	command="tail -F ${file}"
	if [ ! -z $filter ]; then
	command+=" \| grep '${filter}'"
	fi

	trap handle_int INT
	function handle_int() {
	for pid in $(jobs -p)
	do
	kill $pid
	done
	}

	for host in $hosts
	do
	ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no ${username}@${host} "${command}" &
	done

	wait