Add support for host names in config address fields, resolve them to IP

src/util/serde.rs

@@ -0,0 +1,30 @@
+use std::net::{SocketAddr, ToSocketAddrs};
+
+use serde::de::{Error, Unexpected};
+use serde::{Deserialize, Deserializer};
+
+/// Deserialize a `Vec` into a `HashMap` by key.
+pub fn to_socket_addrs<'de, D>(d: D) -> Result<SocketAddr, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    // Deserialize string
+    let addr = String::deserialize(d)?;
+
+    // Try to socket address to resolve
+    match addr.to_socket_addrs() {
+        Ok(mut addr) => {
+            if let Some(addr) = addr.next() {
+                return Ok(addr);
+            }
+        }
+        Err(err) => {
+            dbg!(err);
+        }
+    }
+
+    // Parse raw IP address
+    addr.parse().map_err(|_| {
+        Error::invalid_value(Unexpected::Str(&addr), &"IP or resolvable host and port")
+    })
+}