#! /bin/sh

# debug
set -x
set -v

# Get initial cluster data from metadata
NAME_PREFIX="$(cat /etc/etcd/name_prefix)"
INIT_CLUSTER="$(cat /etc/etcd/init_cluster)"

# Wait till we have an IP address
IP=""
while [ -z "$IP" ]; do
    IP=$(ifconfig eth0 2>/dev/null|awk '/inet addr:/ {print $2}'|sed 's/addr://')
    sleep 1
done

# Where to store data
DATADIR=/var/lib/etcd

# Name is NAME_PREFIX+last octet of IP address
NUM=$(echo ${IP} | cut -d . -f 4)
NAME=${NAME_PREFIX}${NUM}

# We currently have no easy way to determine if we join a cluster for
# the first time or if we got restarted and need to join an existing
# cluster. So we first try joining a *new* cluster. This fails if we
# had already joined it previously. As a fallback we then try to join
# an existing cluster.

# Try to join an new cluster
/usr/local/bin/etcd \
    --name ${NAME} \
    --debug \
    --log-package-levels etcdmain=DEBUG,etcdserver=DEBUG \
    --data-dir $DATADIR \
    --initial-advertise-peer-urls http://${IP}:2380 \
    --listen-peer-urls http://${IP}:2380 \
    --listen-client-urls http://${IP}:2379,http://127.0.0.1:2379 \
    --advertise-client-urls http://${IP}:2379 \
    --initial-cluster-token etcd-cluster-1 \
    --initial-cluster ${INIT_CLUSTER} \
    --initial-cluster-state new

[ $? -eq 0 ] && exit 0

# Try to join an existing cluster
/usr/local/bin/etcd \
    --name ${NAME} \
    --debug \
    --log-package-levels etcdmain=DEBUG,etcdserver=DEBUG \
    --data-dir $DATADIR \
    --initial-advertise-peer-urls http://${IP}:2380 \
    --listen-peer-urls http://${IP}:2380 \
    --listen-client-urls http://${IP}:2379,http://127.0.0.1:2379 \
    --advertise-client-urls http://${IP}:2379 \
    --initial-cluster ${INIT_CLUSTER} \
    --initial-cluster-state existing