From 4b2af055dce4f2a186c727d3df6e30e573faa78c Mon Sep 17 00:00:00 2001
From: Jesse de Wit <witdejesse@hotmail.com>
Date: Tue, 29 Oct 2024 12:02:46 +0100
Subject: [PATCH] reconnect breez server on hibernation

---
 libs/sdk-common/Cargo.toml          |  2 +-
 libs/sdk-common/src/breez_server.rs | 25 +++++++++++++++++--------
 libs/sdk-core/src/breez_services.rs | 14 ++++++++++++++
 tools/sdk-cli/Cargo.lock            |  1 +
 4 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/libs/sdk-common/Cargo.toml b/libs/sdk-common/Cargo.toml
index 585918449..d124fe9e8 100644
--- a/libs/sdk-common/Cargo.toml
+++ b/libs/sdk-common/Cargo.toml
@@ -22,6 +22,7 @@ serde = { workspace = true }
 serde_json = { workspace = true }
 strum_macros = { workspace = true }
 thiserror = { workspace = true }
+tokio = { workspace = true }
 tonic = { workspace = true, features = [
     "tls",
     "transport",
@@ -35,7 +36,6 @@ urlencoding = { version = "2.1.3" }
 [dev-dependencies]
 bitcoin = { workspace = true, features = ["rand"] }
 mockito = { workspace = true }
-tokio = { workspace = true }
 once_cell = { workspace = true }
 
 [build-dependencies]
diff --git a/libs/sdk-common/src/breez_server.rs b/libs/sdk-common/src/breez_server.rs
index cc7ca0b4f..f1e10b6a2 100644
--- a/libs/sdk-common/src/breez_server.rs
+++ b/libs/sdk-common/src/breez_server.rs
@@ -1,5 +1,6 @@
 use anyhow::Result;
 use log::trace;
+use tokio::sync::Mutex;
 use tonic::codegen::InterceptedService;
 use tonic::metadata::errors::InvalidMetadataValue;
 use tonic::metadata::{Ascii, MetadataValue};
@@ -20,18 +21,26 @@ pub static PRODUCTION_BREEZSERVER_URL: &str = "https://bs1.breez.technology:443"
 pub static STAGING_BREEZSERVER_URL: &str = "https://bs1-st.breez.technology:443";
 
 pub struct BreezServer {
-    grpc_channel: Channel,
+    grpc_channel: Mutex<Channel>,
     api_key: Option<String>,
+    server_url: String,
 }
 
 impl BreezServer {
     pub fn new(server_url: String, api_key: Option<String>) -> Result<Self> {
         Ok(Self {
-            grpc_channel: Endpoint::from_shared(server_url)?.connect_lazy(),
+            grpc_channel: Mutex::new(Endpoint::from_shared(server_url.clone())?.connect_lazy()),
             api_key,
+            server_url,
         })
     }
 
+    pub async fn reconnect(&self) -> Result<()> {
+        *self.grpc_channel.lock().await =
+            Endpoint::from_shared(self.server_url.clone())?.connect_lazy();
+        Ok(())
+    }
+
     fn api_key_metadata(&self) -> Result<Option<MetadataValue<Ascii>>, ServiceConnectivityError> {
         match &self.api_key {
             Some(key) => Ok(Some(format!("Bearer {key}").parse().map_err(
@@ -54,22 +63,22 @@ impl BreezServer {
     > {
         let api_key_metadata = self.api_key_metadata()?;
         let with_interceptor = ChannelOpenerClient::with_interceptor(
-            self.grpc_channel.clone(),
+            self.grpc_channel.lock().await.clone(),
             ApiKeyInterceptor { api_key_metadata },
         );
         Ok(with_interceptor)
     }
 
     pub async fn get_payment_notifier_client(&self) -> PaymentNotifierClient<Channel> {
-        PaymentNotifierClient::new(self.grpc_channel.clone())
+        PaymentNotifierClient::new(self.grpc_channel.lock().await.clone())
     }
 
     pub async fn get_information_client(&self) -> InformationClient<Channel> {
-        InformationClient::new(self.grpc_channel.clone())
+        InformationClient::new(self.grpc_channel.lock().await.clone())
     }
 
     pub async fn get_signer_client(&self) -> SignerClient<Channel> {
-        SignerClient::new(self.grpc_channel.clone())
+        SignerClient::new(self.grpc_channel.lock().await.clone())
     }
 
     pub async fn get_support_client(
@@ -80,13 +89,13 @@ impl BreezServer {
     > {
         let api_key_metadata = self.api_key_metadata()?;
         Ok(SupportClient::with_interceptor(
-            self.grpc_channel.clone(),
+            self.grpc_channel.lock().await.clone(),
             ApiKeyInterceptor { api_key_metadata },
         ))
     }
 
     pub async fn get_swapper_client(&self) -> SwapperClient<Channel> {
-        SwapperClient::new(self.grpc_channel.clone())
+        SwapperClient::new(self.grpc_channel.lock().await.clone())
     }
 
     pub async fn ping(&self) -> Result<String> {
diff --git a/libs/sdk-core/src/breez_services.rs b/libs/sdk-core/src/breez_services.rs
index c6c9022b5..e16e5d4d2 100644
--- a/libs/sdk-core/src/breez_services.rs
+++ b/libs/sdk-core/src/breez_services.rs
@@ -2465,6 +2465,20 @@ impl BreezServicesBuilder {
             }
         });
 
+        // Reconnect breez server on hibernation.
+        let cloned_breez_server = breez_server.clone();
+        let mut cloned_hibernation_receiver = hibernation_receiver.clone();
+        tokio::spawn(async move {
+            loop {
+                if cloned_hibernation_receiver.changed().await.is_err() {
+                    return;
+                }
+
+                debug!("Reconnect hibernation: reconnecting breez server");
+                let _ = cloned_breez_server.reconnect().await;
+            }
+        });
+
         let current_lsp_id = persister.get_lsp_id()?;
         if current_lsp_id.is_none() && self.config.default_lsp_id.is_some() {
             persister.set_lsp(self.config.default_lsp_id.clone().unwrap(), None)?;
diff --git a/tools/sdk-cli/Cargo.lock b/tools/sdk-cli/Cargo.lock
index 36d4140ca..9e5daeffa 100644
--- a/tools/sdk-cli/Cargo.lock
+++ b/tools/sdk-cli/Cargo.lock
@@ -2996,6 +2996,7 @@ dependencies = [
  "serde_json",
  "strum_macros",
  "thiserror",
+ "tokio",
  "tonic",
  "tonic-build",
  "url",