From f914eefbdd613ac433bf99067941c8d6d1f9f9c5 Mon Sep 17 00:00:00 2001
From: Yevhenii Babichenko <eugene.babichenko@iohk.io>
Date: Wed, 20 Nov 2019 19:39:00 +0200
Subject: [PATCH] avoid empty vectors in TrustedAddress::to_addresses

---
 jormungandr/src/settings/start/config.rs | 29 +++++++++++++++---------
 jormungandr/src/settings/start/mod.rs    | 16 ++++++++-----
 2 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/jormungandr/src/settings/start/config.rs b/jormungandr/src/settings/start/config.rs
index 62808cc1b5..6578c630b8 100644
--- a/jormungandr/src/settings/start/config.rs
+++ b/jormungandr/src/settings/start/config.rs
@@ -222,7 +222,7 @@ custom_error! {pub AddressError
 }
 
 impl TrustedAddress {
-    pub fn to_addresses(&self) -> Result<Vec<Address>, AddressError> {
+    pub fn to_addresses(&self) -> Result<Option<Vec<Address>>, AddressError> {
         use multiaddr::AddrComponent;
         use std::iter::FromIterator;
         use trust_dns_proto::rr::{record_data::RData, RecordType};
@@ -254,20 +254,27 @@ impl TrustedAddress {
                 .collect(),
             Some(AddrComponent::IP4(addr)) => vec![AddrComponent::IP4(addr)],
             Some(AddrComponent::IP6(addr)) => vec![AddrComponent::IP6(addr)],
-            _ => Vec::new(),
+            _ => return Ok(None),
         };
 
+        if addresses.is_empty() {
+            return Ok(None);
+        }
+
         if let Some(AddrComponent::TCP(port)) = components.next() {
-            Ok(addresses
-                .into_iter()
-                .map(|addr| {
-                    let new_components = vec![addr, AddrComponent::TCP(port)];
-                    let new_multiaddr = multiaddr::Multiaddr::from_iter(new_components.into_iter());
-                    Address(poldercast::Address::new(new_multiaddr).unwrap())
-                })
-                .collect())
+            Ok(Some(
+                addresses
+                    .into_iter()
+                    .map(|addr| {
+                        let new_components = vec![addr, AddrComponent::TCP(port)];
+                        let new_multiaddr =
+                            multiaddr::Multiaddr::from_iter(new_components.into_iter());
+                        Address(poldercast::Address::new(new_multiaddr).unwrap())
+                    })
+                    .collect(),
+            ))
         } else {
-            Ok(Vec::new())
+            Ok(None)
         }
     }
 }
diff --git a/jormungandr/src/settings/start/mod.rs b/jormungandr/src/settings/start/mod.rs
index 2bb03b5e28..cfac2c7191 100644
--- a/jormungandr/src/settings/start/mod.rs
+++ b/jormungandr/src/settings/start/mod.rs
@@ -182,6 +182,8 @@ fn generate_network(
     command_arguments: &StartArguments,
     config: &Option<Config>,
 ) -> Result<network::Configuration, Error> {
+    use crate::settings::start::network::TrustedPeer;
+
     let mut p2p = if let Some(cfg) = config {
         cfg.p2p.clone()
     } else {
@@ -235,14 +237,16 @@ fn generate_network(
             .unwrap_or(vec![])
             .into_iter()
             .filter_map(|tp| {
-                tp.address.to_addresses().ok().map(|addrs| {
-                    addrs.into_iter().map(move |address| {
-                        crate::settings::start::network::TrustedPeer {
+                tp.address
+                    .to_addresses()
+                    .ok()
+                    .and_then(std::convert::identity)
+                    .map(|addrs| {
+                        addrs.into_iter().map(move |addr| TrustedPeer {
                             id: tp.id.clone(),
-                            address: address.0,
-                        }
+                            address: addr.0,
+                        })
                     })
-                })
             })
             .flatten()
             .collect(),