agent: clean up

agent/agent_cetcd.go

@@ -27,6 +27,7 @@ func startCetcd(fs *flags, t *transporterServer, req *agentpb.Request) (*exec.Cm
 	if !exist(fs.cetcdExec) {
 		return nil, fmt.Errorf("cetcd binary %q does not exist", globalFlags.cetcdExec)
 	}
+
 	peerIPs := strings.Split(req.PeerIPString, "___")
 	clientURLs := make([]string, len(peerIPs))
 	for i, u := range peerIPs {

agent/agent_consul.go

@@ -25,12 +25,14 @@ import (
 
 // startConsul starts Consul.
 func startConsul(fs *flags, t *transporterServer, req *agentpb.Request) (*exec.Cmd, error) {
-	if err := os.RemoveAll(fs.consulDataDir); err != nil {
-		return nil, err
-	}
 	if !exist(fs.consulExec) {
 		return nil, fmt.Errorf("Consul binary %q does not exist", globalFlags.consulExec)
 	}
+
+	if err := os.RemoveAll(fs.consulDataDir); err != nil {
+		return nil, err
+	}
+
 	peerIPs := strings.Split(req.PeerIPString, "___")
 
 	var flags []string

agent/agent_etcd.go

@@ -25,12 +25,14 @@ import (
 
 // startEtcd starts etcd v2 and v3.
 func startEtcd(fs *flags, t *transporterServer, req *agentpb.Request) (*exec.Cmd, error) {
-	if err := os.RemoveAll(fs.etcdDataDir); err != nil {
-		return nil, err
-	}
 	if !exist(fs.etcdExec) {
 		return nil, fmt.Errorf("etcd binary %q does not exist", globalFlags.etcdExec)
 	}
+
+	if err := os.RemoveAll(fs.etcdDataDir); err != nil {
+		return nil, err
+	}
+
 	peerIPs := strings.Split(req.PeerIPString, "___")
 
 	names := make([]string, len(peerIPs))

agent/agent_zookeeper.go

@@ -37,6 +37,9 @@ snapCount={{.SnapCount}}
 {{range .Peers}}server.{{.MyID}}={{.IP}}:2888:3888
 {{end}}
 `
+
+	// this is Zookeeper default configuration
+	// http://zookeeper.apache.org/doc/trunk/zookeeperAdmin.html
 	zkConfigDefault = ZookeeperConfig{
 		TickTime:       2000,
 		ClientPort:     "2181",