fix webrtc and login

src/config.rs

@@ -50,6 +50,10 @@ host = "0.0.0.0"
 tcp_port = 8080
 # WebRTC ICE/Media UDP multiplexing port
 udp_port = 8080
+# Public IPv4 address advertised by ICE when behind NAT (forward udp_port to this server).
+# external_ip = "203.0.113.1"
+# STUN servers used when external_ip is absent; set [] to disable discovery.
+# stun_servers = ["stun:stun.l.google.com:19302"]
 
 # Optional native HTTPS (omit this section to keep plain HTTP behind a proxy).
 # [network.tls]
@@ -110,9 +114,17 @@ pub struct NetworkConfig {
     pub tcp_port: u16,
     pub udp_port: u16,
     #[serde(default)]
+    pub external_ip: Option<Ipv4Addr>,
+    #[serde(default = "default_stun_servers")]
+    pub stun_servers: Vec<String>,
+    #[serde(default)]
     pub tls: Option<TlsConfig>,
 }
 
+fn default_stun_servers() -> Vec<String> {
+    vec!["stun:stun.l.google.com:19302".to_string()]
+}
+
 #[derive(Debug, Clone, Deserialize)]
 pub struct TlsConfig {
     pub cert_path: std::path::PathBuf,
@@ -170,3 +182,38 @@ impl AppConfig {
         Self::load()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::{AppConfig, DEFAULT_CONFIG_TOML};
+    use std::net::Ipv4Addr;
+
+    #[test]
+    fn external_ip_is_optional_and_accepts_public_ipv4() {
+        let default: AppConfig = toml::from_str(DEFAULT_CONFIG_TOML).unwrap();
+        assert_eq!(default.network.external_ip, None);
+        assert_eq!(default.network.stun_servers, vec!["stun:stun.l.google.com:19302"]);
+
+        let configured = DEFAULT_CONFIG_TOML.replace(
+            "# external_ip = \"203.0.113.1\"",
+            "external_ip = \"203.0.113.1\"",
+        );
+        let config: AppConfig = toml::from_str(&configured).unwrap();
+        assert_eq!(config.network.external_ip, Some(Ipv4Addr::new(203, 0, 113, 1)));
+    }
+
+    #[test]
+    fn stun_servers_can_be_disabled_or_replaced() {
+        for (value, expected) in [
+            ("[]", vec![]),
+            ("[\"stun:example.org:3478\"]", vec!["stun:example.org:3478"]),
+        ] {
+            let text = DEFAULT_CONFIG_TOML.replace(
+                "# stun_servers = [\"stun:stun.l.google.com:19302\"]",
+                &format!("stun_servers = {value}"),
+            );
+            let config: AppConfig = toml::from_str(&text).unwrap();
+            assert_eq!(config.network.stun_servers, expected);
+        }
+    }
+}