seanmcgary / proxy-watcher

Companion process to watch etcd for nodes joining/leaving a cluster

proxy-watcher

Proxy-watcher is a NodeJS module that is designed to be deployed with a load balancer to listen for nodes joining and leaving the cluster.

Proxy-watcher works by watching a key through etcd, creating an updated config, and reloading your load balancer automatically. When looking at nodes in etcd, it expects the following structure as the value (as a JSON string)

{
	host: 'my-nodes-hostname-or-ip-address',
	port: 1234
}

Environment Variables/Config

PROXY_WATCHER_ETCD_SECURE=false

# etcd node to connect to
PROXY_WATCHER_ETCD_CLUSTER_HOST="127.0.0.1"
PROXY_WATCHER_ETCD_CLUSTER_PORT="4001"

# the path/key to watch in etcd
PROXY_WATCHER_ETCD_PATH="/some_dir"

# the config file to write out to
PROXY_WATCHER_CONFIG_PATH="/etc/haproxy/haproxy.conf"

# the command used to reload your proxy/load balancer
PROXY_WATCHER_RELOAD_COMMAND="sudo service haproxy reload"

Running proxy watcher

node proxy-watcher <path to config template>