set default value for local_network_id

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "chaindev"
-version = "0.50.2"
+version = "0.51.0"
 edition = "2021"
 authors = ["hui.fan@mail.ru"]
 description = "Powerful development and testing utils for blockchain developers."

src/common/hosts.rs

@@ -10,11 +10,15 @@ use std::{
 #[derive(Clone, Debug, Ord, PartialOrd, Eq, PartialEq, Serialize, Deserialize)]
 pub struct HostAddr {
     pub local_ip: String,
-    #[serde(default)]
+    #[serde(default = "default_local_network_id")]
     pub local_network_id: String,
     pub ext_ip: Option<String>,
 }
 
+fn default_local_network_id() -> String {
+    "default_mlm_mmm_lqm_qmzl_9527".to_owned()
+}
+
 impl HostAddr {
     #[inline(always)]
     pub fn connection_addr(&self) -> &str {
@@ -24,8 +28,7 @@ impl HostAddr {
     /// Use the local ip to get better performance,
     /// if they are locating in the same local network
     pub fn connection_addr_x(&self, local_network_id: &str) -> &str {
-        if !self.local_network_id.is_empty()
-            && self.local_network_id == local_network_id
+        if self.local_network_id == local_network_id
         {
             &self.local_ip
         } else {