new GatewaySetup variant to reuse the connection

clients/native/src/commands/init.rs

@@ -174,7 +174,7 @@ pub(crate) async fn execute(args: &Init) -> Result<(), ClientError> {
     let details_store =
         OnDiskGatewayDetails::new(&config.storage_paths.common_paths.gateway_details);
     let init_details = nym_client_core::init::setup_gateway(
-        &gateway_setup,
+        gateway_setup,
         &key_store,
         &details_store,
         register_gateway,

clients/socks5/src/commands/init.rs

@@ -186,7 +186,7 @@ pub(crate) async fn execute(args: &Init) -> Result<(), Socks5ClientError> {
     let details_store =
         OnDiskGatewayDetails::new(&config.storage_paths.common_paths.gateway_details);
     let init_details = nym_client_core::init::setup_gateway(
-        &gateway_setup,
+        gateway_setup,
         &key_store,
         &details_store,
         register_gateway,

clients/webassembly/src/helpers.rs

@@ -89,7 +89,7 @@ async fn setup_gateway(
         GatewaySetup::new_fresh(chosen_gateway.clone(), None)
     };
 
-    setup_gateway_from(&setup, client_store, client_store, false, Some(gateways))
+    setup_gateway_from(setup, client_store, client_store, false, Some(gateways))
         .await
         .map_err(Into::into)
 }

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

@@ -455,17 +455,23 @@ where
         Ok(mem_store)
     }
 
-    async fn initialise_keys_and_gateway(&self) -> Result<InitialisationResult, ClientCoreError>
+    async fn initialise_keys_and_gateway(
+        setup_method: GatewaySetup,
+        key_store: &S::KeyStore,
+        details_store: &S::GatewayDetailsStore,
+        overwrite_data: bool,
+        validator_servers: Option<&[Url]>,
+    ) -> Result<InitialisationResult, ClientCoreError>
     where
         <S::KeyStore as KeyStore>::StorageError: Sync + Send,
         <S::GatewayDetailsStore as GatewayDetailsStore>::StorageError: Sync + Send,
     {
         setup_gateway(
-            &self.setup_method,
-            self.client_store.key_store(),
-            self.client_store.gateway_details_store(),
-            false,
-            Some(&self.config.client.nym_api_urls),
+            setup_method,
+            key_store,
+            details_store,
+            overwrite_data,
+            validator_servers,
         )
         .await
     }
@@ -481,7 +487,14 @@ where
         info!("Starting nym client");
 
         // derive (or load) client keys and gateway configuration
-        let init_res = self.initialise_keys_and_gateway().await?;
+        let init_res = Self::initialise_keys_and_gateway(
+            self.setup_method,
+            self.client_store.key_store(),
+            self.client_store.gateway_details_store(),
+            false,
+            Some(&self.config.client.nym_api_urls),
+        )
+        .await?;
 
         let (reply_storage_backend, credential_store) = self.client_store.into_runtime_stores();
 

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

@@ -97,7 +97,6 @@ impl InitialisationDetails {
     }
 }
 
-#[derive(Debug, Clone)]
 pub enum GatewaySetup {
     /// The gateway specification MUST BE loaded from the underlying storage.
     MustLoad,
@@ -115,6 +114,13 @@ pub enum GatewaySetup {
         /// Full gateway configuration
         details: PersistedGatewayDetails,
     },
+    ReuseConnection {
+        /// The authenticated ephemeral client that was created during `init`
+        authenticated_ephemeral_client: GatewayClient<InitOnly>,
+
+        /// Details of this pre-initialised client
+        details: InitialisationDetails,
+    },
 }
 
 impl From<PersistedGatewayDetails> for GatewaySetup {
@@ -289,7 +295,7 @@ fn ensure_valid_details(
 }
 
 pub async fn setup_gateway_from<K, D>(
-    setup: &GatewaySetup,
+    setup: GatewaySetup,
     key_store: &K,
     details_store: &D,
     overwrite_data: bool,
@@ -301,6 +307,20 @@ where
     K::StorageError: Send + Sync + 'static,
     D::StorageError: Send + Sync + 'static,
 {
+    // I don't like how we can't deal with this variant in the match below, but we need to take ownership of internal values.
+    if let GatewaySetup::ReuseConnection {
+        authenticated_ephemeral_client,
+        details,
+    } = setup
+    {
+        // if we have already performed the full setup, forward the details.
+        // it's up to the caller to ensure persistence
+        return Ok(InitialisationResult {
+            details,
+            authenticated_ephemeral_client: Some(authenticated_ephemeral_client),
+        });
+    }
+
     let mut rng = OsRng;
 
     // try load gateway details
@@ -309,7 +329,7 @@ where
     // try load keys and decide what to do based on the GatewaySetup
     let mut managed_keys = match ManagedKeys::try_load(key_store).await {
         Ok(loaded_keys) => {
-            match setup {
+            match &setup {
                 GatewaySetup::MustLoad => {
                     // get EVERYTHING from the storage
                     let details = loaded_details?;
@@ -376,6 +396,9 @@ where
                         return Err(ClientCoreError::ForbiddenKeyOverwrite);
                     }
                 }
+                GatewaySetup::ReuseConnection { .. } => {
+                    unreachable!("the reuse connection variant was already manually covered")
+                }
             }
         }
         Err(_) => {
@@ -419,7 +442,7 @@ where
 }
 
 pub async fn setup_gateway<K, D>(
-    setup: &GatewaySetup,
+    setup: GatewaySetup,
     key_store: &K,
     details_store: &D,
     overwrite_data: bool,

common/client-libs/gateway-client/src/client.rs

@@ -809,6 +809,12 @@ impl GatewayClient<InitOnly, EphemeralCredentialStorage> {
         bandwidth_controller: Option<BandwidthController<C, St>>,
         shutdown: TaskClient,
     ) -> GatewayClient<C, St> {
+        // invariants that can't be broken
+        // (unless somebody decided to expose some field that wasn't meant to be exposed)
+        assert!(self.authenticated);
+        assert!(self.connection.is_available());
+        assert!(self.shared_key.is_some());
+
         GatewayClient {
             authenticated: self.authenticated,
             disabled_credentials_mode: self.disabled_credentials_mode,

nym-connect/desktop/src-tauri/src/config/mod.rs

@@ -183,7 +183,7 @@ pub async fn init_socks5_config(provider_address: String, chosen_gateway_id: Str
     let details_store =
         OnDiskGatewayDetails::new(&config.storage_paths.common_paths.gateway_details);
     let init_details = nym_client_core::init::setup_gateway(
-        &gateway_setup,
+        gateway_setup,
         &key_store,
         &details_store,
         register_gateway,

sdk/rust/nym-sdk/src/mixnet/client.rs

@@ -323,7 +323,7 @@ where
 
         // this will perform necessary key and details load and optional store
         let _init_result = nym_client_core::init::setup_gateway(
-            &gateway_setup,
+            gateway_setup,
             self.storage.key_store(),
             self.storage.gateway_details_store(),
             !self.config.key_mode.is_keep(),

service-providers/network-requester/src/cli/init.rs

@@ -149,7 +149,7 @@ pub(crate) async fn execute(args: &Init) -> Result<(), NetworkRequesterError> {
     let details_store =
         OnDiskGatewayDetails::new(&config.storage_paths.common_paths.gateway_details);
     let init_details = nym_client_core::init::setup_gateway(
-        &gateway_setup,
+        gateway_setup,
         &key_store,
         &details_store,
         register_gateway,