This is a simple Go program that generates a text file suitable for the swarm file discovery backend
go get -u github.com/ejholmes/swarm-ecs/cmd/swarm-ecs
List the hosts within the cluster:
$ swarm-ecs list
<node_ip1:2375>
<node_ip2:2375>
<node_ip3:2375>Periodically write it to a file that swarm is watching:
$ swarm manage -H tcp://<swarm_ip:swarm_port> file:///tmp/my_cluster &
$ while true; do swarm-ecs list > /tmp/my_cluster; sleep 1; done