nym-connect: select gateway based on latency in medium mode

common/client-core/src/client/topology_control/geo_aware_provider.rs

@@ -303,7 +303,7 @@ impl GeoAwareTopologyProvider {
         filter_on: GroupBy,
     ) -> GeoAwareTopologyProvider {
         log::info!(
-            "Creating geo-aware topology provider with filter on {:?}",
+            "Creating geo-aware topology provider with filter on {}",
             filter_on
         );
         nym_api_urls.shuffle(&mut thread_rng());

common/client-core/src/config/mod.rs

@@ -498,6 +498,15 @@ pub enum GroupBy {
     NymAddress(Recipient),
 }
 
+impl std::fmt::Display for GroupBy {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            GroupBy::CountryGroup(group) => write!(f, "group: {}", group),
+            GroupBy::NymAddress(address) => write!(f, "address: {}", address),
+        }
+    }
+}
+
 impl Default for Topology {
     fn default() -> Self {
         Topology {

common/client-core/src/init/helpers.rs

@@ -149,7 +149,7 @@ async fn measure_latency(gateway: &gateway::Node) -> Result<GatewayWithLatency,
     Ok(GatewayWithLatency::new(gateway, avg))
 }
 
-pub(super) async fn choose_gateway_by_latency<R: Rng>(
+pub async fn choose_gateway_by_latency<R: Rng>(
     rng: &mut R,
     gateways: &[gateway::Node],
 ) -> Result<gateway::Node, ClientCoreError> {

nym-connect/desktop/Cargo.lock

@@ -4014,8 +4014,10 @@ dependencies = [
  "nym-socks5-client-core",
  "nym-sphinx",
  "nym-task",
+ "nym-topology",
  "nym-validator-client",
  "pretty_env_logger",
+ "rand 0.7.3",
  "rand 0.8.5",
  "reqwest",
  "rust-embed",

nym-connect/desktop/Cargo.toml

@@ -1,2 +1,3 @@
 [workspace]
 members = ["src-tauri"]
+resolver = "2"

nym-connect/desktop/src-tauri/Cargo.toml

@@ -30,6 +30,7 @@ itertools = "0.10.5"
 log = { version = "0.4", features = ["serde"] }
 pretty_env_logger = "0.4.0"
 rand = "0.8"
+rand-07 = { package = "rand", version = "0.7.3" }
 reqwest = { version = "0.11.18", features = ["json", "socks"] }
 rust-embed = { version = "6.4.2", features = ["include-exclude"] }
 serde = { version = "1.0", features = ["derive"] }
@@ -58,6 +59,7 @@ nym-bin-common = { path = "../../../common/bin-common"}
 nym-socks5-client-core = { path = "../../../common/socks5-client-core" }
 nym-sphinx = { path = "../../../common/nymsphinx" }
 nym-task = { path = "../../../common/task" }
+nym-topology = { path = "../../../common/topology" }
 nym-validator-client = { path = "../../../common/client-libs/validator-client" }
 
 [dev-dependencies]

nym-connect/desktop/src-tauri/src/main.rs

@@ -86,8 +86,10 @@ fn main() {
             crate::operations::connection::status::get_connection_status,
             crate::operations::connection::status::get_gateway_connection_status,
             crate::operations::connection::status::start_connection_health_check_task,
-            crate::operations::directory::get_services,
+            crate::operations::directory::get_gateway_with_low_latency,
+            crate::operations::directory::get_gateway_with_low_latency_from_list,
             crate::operations::directory::get_gateways,
+            crate::operations::directory::get_services,
             crate::operations::export::export_keys,
             crate::operations::window::hide_window,
             crate::operations::growth::test_and_earn::growth_tne_get_client_id,

nym-connect/desktop/src-tauri/src/operations/directory/mod.rs

@@ -11,6 +11,7 @@ use nym_api_requests::models::GatewayBondAnnotated;
 use nym_bin_common::version_checker::is_minor_version_compatible;
 use nym_config::defaults::var_names::{NETWORK_NAME, NYM_API};
 use nym_contracts_common::types::Percent;
+use nym_topology::gateway;
 use nym_validator_client::nym_api::Client as ApiClient;
 use std::str::FromStr;
 use std::sync::Arc;
@@ -164,3 +165,41 @@ pub async fn get_gateways() -> Result<Vec<Gateway>> {
 
     Ok(filtered_gateways)
 }
+
+async fn select_gateway_by_latency(gateways: Vec<GatewayBondAnnotated>) -> Result<gateway::Node> {
+    let gateways_as_nodes: Vec<gateway::Node> = gateways
+        .into_iter()
+        .filter_map(|g| g.gateway_bond.try_into().ok())
+        .collect();
+
+    let mut rng = rand_07::rngs::OsRng;
+    let selected_gateway =
+        nym_client_core::init::helpers::choose_gateway_by_latency(&mut rng, &gateways_as_nodes)
+            .await?;
+    Ok(selected_gateway)
+}
+
+#[tauri::command]
+pub async fn get_gateway_with_low_latency() -> Result<Gateway> {
+    let all_gateways = fetch_gateways().await?;
+    let selected_gateway = select_gateway_by_latency(all_gateways).await?;
+    Ok(Gateway {
+        identity: selected_gateway.identity().to_base58_string(),
+    })
+}
+
+#[tauri::command]
+pub async fn get_gateway_with_low_latency_from_list(gateways: Vec<Gateway>) -> Result<Gateway> {
+    log::debug!("Selecting a gateway with low latency");
+    let gateways = gateways.into_iter().map(|g| g.identity).collect_vec();
+    let all_gateways = fetch_gateways().await?;
+    let gateways_union_set: Vec<GatewayBondAnnotated> = all_gateways
+        .into_iter()
+        .filter(|g| gateways.contains(g.identity()))
+        .collect();
+    let selected_gateway = select_gateway_by_latency(gateways_union_set).await?;
+    log::debug!("Selected gateway: {}", selected_gateway);
+    Ok(Gateway {
+        identity: selected_gateway.identity().to_base58_string(),
+    })
+}

nym-connect/desktop/src-tauri/src/tasks.rs

@@ -57,7 +57,7 @@ fn override_config_from_env(config: &mut Config, privacy_level: &PrivacyLevel) {
             .provider_mix_address
             .parse()
             .expect("failed to parse provider mix address");
-        log::warn!("Using geo-aware mixnode selection baseon the location of: {address}");
+        log::warn!("Using geo-aware mixnode selection based on the location of: {address}");
         config
             .core
             .base

nym-connect/desktop/src/context/main.tsx

@@ -214,7 +214,12 @@ export const ClientContextProvider: FCWithChildren = ({ children }) => {
 
   const setGateway = async () => {
     if (gateways) {
-      const randomGateway = getRandomFromList(gateways);
+      let randomGateway;
+      if (userData?.privacy_level === 'Medium') {
+        randomGateway = await invoke<Gateway>('get_gateway_with_low_latency_from_list', { gateways });
+      } else {
+        randomGateway = getRandomFromList(gateways);
+      }
       const withUserDefinitions = await buildGateway(randomGateway);
       await invoke('set_gateway', {
         gateway: shouldUseUserGateway ? userDefinedGateway.address : withUserDefinitions.identity,