Use blank peer list if saved peer list cannot be read. (#426)

* Use blank peer list if saved peer list cannot be read.

* Format corrections

* The delete operation is not needed.

p2p/address-book/src/lib.rs

@@ -67,8 +67,11 @@ pub async fn init_address_book<Z: BorshNetworkZone>(
         Ok(res) => res,
         Err(e) if e.kind() == ErrorKind::NotFound => (vec![], vec![]),
         Err(e) => {
-            tracing::error!("Failed to open peer list, {}", e);
-            panic!("{e}");
+            tracing::error!(
+                "Error: Failed to open peer list,\n{},\nstarting with an empty list",
+                e
+            );
+            (vec![], vec![])
         }
     };
 

p2p/address-book/src/store.rs

@@ -41,10 +41,15 @@ pub(crate) fn save_peers_to_disk<Z: BorshNetworkZone>(
 
     let dir = cfg.peer_store_directory.clone();
     let file = dir.join(Z::NAME);
+    let mut tmp_file = file.clone();
+    tmp_file.set_extension("tmp");
 
     spawn_blocking(move || {
         fs::create_dir_all(dir)?;
-        fs::write(&file, &data)
+        match fs::write(&tmp_file, &data) {
+            Ok(_) => fs::rename(tmp_file, file),
+            Err(x) => Err(x),
+        }
     })
 }