feat(etcd): create unique directory on no-flag case

Tell etcd to store the log and configuration into directory in the
pattern of `${machineName}.etcd` if no directory is specified.

etcd.go

@@ -47,11 +47,6 @@ func main() {
 		log.Verbose = true
 	}
 
-	// Create data directory if it doesn't already exist.
-	if err := os.MkdirAll(config.DataDir, 0744); err != nil {
-		log.Fatalf("Unable to create path: %s", err)
-	}
-
 	// Load info object.
 	info, err := config.Info()
 	if err != nil {
@@ -66,6 +61,17 @@ func main() {
 		info.Name = host
 	}
 
+	// Setup a default directory based on the machine name
+	if config.DataDir == "" {
+		config.DataDir = info.Name + ".etcd"
+		log.Warnf("Using the directory %s as the etcd configuration directory because a directory was not specified. ", config.DataDir)
+	}
+
+	// Create data directory if it doesn't already exist.
+	if err := os.MkdirAll(config.DataDir, 0744); err != nil {
+		log.Fatalf("Unable to create path: %s", err)
+	}
+
 	// Retrieve TLS configuration.
 	tlsConfig, err := info.EtcdTLS.Config()
 	if err != nil {

server/config.go

@@ -57,7 +57,6 @@ func NewConfig() *Config {
 	c.SystemPath = DefaultSystemConfigPath
 	c.AdvertisedUrl = "127.0.0.1:4001"
 	c.AdvertisedUrl = "127.0.0.1:4001"
-	c.DataDir = "."
 	c.MaxClusterSize = 9
 	c.MaxResultBuffer = 1024
 	c.MaxRetryAttempts = 3