Use configured lazy connect channel in sync service

lib/core/src/sync/client.rs

@@ -1,8 +1,16 @@
-use anyhow::{anyhow, Result};
+use std::time::Duration;
+
+use anyhow::{anyhow, Error, Result};
 
 use async_trait::async_trait;
 use log::debug;
 use tokio::sync::Mutex;
+use tonic::{
+    metadata::{errors::InvalidMetadataValue, Ascii, MetadataValue},
+    service::{interceptor::InterceptedService, Interceptor},
+    transport::{Channel, ClientTlsConfig, Endpoint},
+    Request, Status,
+};
 
 use super::model::sync::{
     syncer_client::SyncerClient as ProtoSyncerClient, ListChangesReply, ListChangesRequest,
@@ -18,58 +26,97 @@ pub(crate) trait SyncerClient: Send + Sync {
 }
 
 pub(crate) struct BreezSyncerClient {
-    inner: Mutex<Option<ProtoSyncerClient<tonic::transport::Channel>>>,
+    grpc_channel: Mutex<Option<Channel>>,
     api_key: Option<String>,
 }
 
 impl BreezSyncerClient {
     pub(crate) fn new(api_key: Option<String>) -> Self {
         Self {
-            inner: Default::default(),
+            grpc_channel: Mutex::new(None),
             api_key,
         }
     }
+
+    fn create_endpoint(server_url: &str) -> Result<Endpoint> {
+        Ok(Endpoint::from_shared(server_url.to_string())?
+            .http2_keep_alive_interval(Duration::new(5, 0))
+            .tcp_keepalive(Some(Duration::from_secs(5)))
+            .keep_alive_timeout(Duration::from_secs(5))
+            .keep_alive_while_idle(true)
+            .tls_config(ClientTlsConfig::new().with_enabled_roots())?)
+    }
+
+    fn api_key_metadata(&self) -> Result<Option<MetadataValue<Ascii>>, Error> {
+        match &self.api_key {
+            Some(key) => Ok(Some(format!("Bearer {key}").parse().map_err(
+                |e: InvalidMetadataValue| {
+                    anyhow!(format!(
+                        "(Breez: {:?}) Failed parse API key: {e}",
+                        self.api_key
+                    ))
+                },
+            )?)),
+            _ => Ok(None),
+        }
+    }
 }
 
 impl BreezSyncerClient {
-    fn set_api_key<T>(&self, req: T) -> Result<tonic::Request<T>> {
-        let mut req = tonic::Request::new(req);
-        if let Some(api_key) = &self.api_key {
-            let metadata = req.metadata_mut();
-            metadata.insert("authorization", format!("Bearer {}", api_key).parse()?);
-        }
-        Ok(req)
+    async fn get_client(
+        &self,
+    ) -> Result<ProtoSyncerClient<InterceptedService<Channel, ApiKeyInterceptor>>, Error> {
+        let Some(channel) = self.grpc_channel.lock().await.clone() else {
+            return Err(anyhow!("Cannot get sync client: not connected"));
+        };
+        let api_key_metadata = self.api_key_metadata()?;
+        Ok(ProtoSyncerClient::with_interceptor(
+            channel,
+            ApiKeyInterceptor { api_key_metadata },
+        ))
     }
 }
 
 #[async_trait]
 impl SyncerClient for BreezSyncerClient {
     async fn connect(&self, connect_url: String) -> Result<()> {
-        let mut client = self.inner.lock().await;
-        *client = Some(ProtoSyncerClient::connect(connect_url.clone()).await?);
+        let mut grpc_channel = self.grpc_channel.lock().await;
+        *grpc_channel = Some(Self::create_endpoint(&connect_url)?.connect_lazy());
         debug!("Successfully connected to {connect_url}");
         Ok(())
     }
 
     async fn push(&self, req: SetRecordRequest) -> Result<SetRecordReply> {
-        let Some(mut client) = self.inner.lock().await.clone() else {
-            return Err(anyhow!("Cannot run `set_record`: client not connected"));
-        };
-        let req = self.set_api_key(req)?;
-        Ok(client.set_record(req).await?.into_inner())
+        Ok(self.get_client().await?.set_record(req).await?.into_inner())
     }
 
     async fn pull(&self, req: ListChangesRequest) -> Result<ListChangesReply> {
-        let Some(mut client) = self.inner.lock().await.clone() else {
-            return Err(anyhow!("Cannot run `list_changes`: client not connected"));
-        };
-        let req = self.set_api_key(req)?;
-        Ok(client.list_changes(req).await?.into_inner())
+        Ok(self
+            .get_client()
+            .await?
+            .list_changes(req)
+            .await?
+            .into_inner())
     }
 
     async fn disconnect(&self) -> Result<()> {
-        let mut client = self.inner.lock().await;
-        *client = None;
+        let mut channel = self.grpc_channel.lock().await;
+        *channel = None;
         Ok(())
     }
 }
+
+#[derive(Clone)]
+pub struct ApiKeyInterceptor {
+    api_key_metadata: Option<MetadataValue<Ascii>>,
+}
+
+impl Interceptor for ApiKeyInterceptor {
+    fn call(&mut self, mut req: Request<()>) -> Result<Request<()>, Status> {
+        if self.api_key_metadata.clone().is_some() {
+            req.metadata_mut()
+                .insert("authorization", self.api_key_metadata.clone().unwrap());
+        }
+        Ok(req)
+    }
+}