Make `WalletInfo` in feed optional

In case the wallet sync fails, we replace the value with `None` to
indicate to the UI that we don't have an up-to-date wallet information.
In case the sync works again at some point, we will replace it with
`Some` again.

Making this optional also allows us to start up the system without
syncing the wallet, a step towards https://github.com/itchysats/itchysats/discussions/753.

daemon/src/maker.rs

@@ -5,7 +5,6 @@ use bdk::{bitcoin, FeeRate};
 use clap::{Parser, Subcommand};
 use daemon::auth::{self, MAKER_USERNAME};
 use daemon::model::cfd::Role;
-use daemon::model::WalletInfo;
 use daemon::seed::Seed;
 use daemon::tokio_ext::FutureExt;
 use daemon::{
@@ -205,7 +204,7 @@ async fn main() -> Result<()> {
         "ddd4636845a90185991826be5a494cde9f4a6947b1727217afedc6292fa4caf7",
     )?;
 
-    let (wallet_feed_sender, wallet_feed_receiver) = watch::channel::<WalletInfo>(wallet_info);
+    let (wallet_feed_sender, wallet_feed_receiver) = watch::channel(Some(wallet_info));
 
     let figment = rocket::Config::figment()
         .merge(("address", opts.http_address.ip()))

daemon/src/routes_maker.rs

@@ -29,7 +29,7 @@ pub type Maker = xtra::Address<
 #[rocket::get("/feed")]
 pub async fn maker_feed(
     rx: &State<Feeds>,
-    rx_wallet: &State<watch::Receiver<WalletInfo>>,
+    rx_wallet: &State<watch::Receiver<Option<WalletInfo>>>,
     _auth: Authenticated,
 ) -> EventStream![] {
     let rx = rx.inner();

daemon/src/routes_taker.rs

@@ -25,7 +25,7 @@ type Taker = xtra::Address<taker_cfd::Actor<oracle::Actor, monitor::Actor, walle
 #[rocket::get("/feed")]
 pub async fn feed(
     rx: &State<Feeds>,
-    rx_wallet: &State<watch::Receiver<WalletInfo>>,
+    rx_wallet: &State<watch::Receiver<Option<WalletInfo>>>,
     rx_maker_status: &State<watch::Receiver<ConnectionStatus>>,
 ) -> EventStream![] {
     let rx = rx.inner();

daemon/src/taker.rs

@@ -5,7 +5,7 @@ use bdk::{bitcoin, FeeRate};
 use clap::{Parser, Subcommand};
 use daemon::connection::connect;
 use daemon::model::cfd::Role;
-use daemon::model::{Identity, WalletInfo};
+use daemon::model::Identity;
 use daemon::seed::Seed;
 use daemon::tokio_ext::FutureExt;
 use daemon::{
@@ -204,7 +204,7 @@ async fn main() -> Result<()> {
         "ddd4636845a90185991826be5a494cde9f4a6947b1727217afedc6292fa4caf7",
     )?;
 
-    let (wallet_feed_sender, wallet_feed_receiver) = watch::channel::<WalletInfo>(wallet_info);
+    let (wallet_feed_sender, wallet_feed_receiver) = watch::channel(Some(wallet_info));
 
     let mut tasks = Tasks::default();
 

daemon/src/to_sse_event.rs

@@ -46,13 +46,13 @@ pub struct WalletInfo {
     last_updated_at: Timestamp,
 }
 
-impl ToSseEvent for model::WalletInfo {
+impl ToSseEvent for Option<model::WalletInfo> {
     fn to_sse_event(&self) -> Event {
-        let wallet_info = WalletInfo {
-            balance: self.balance,
-            address: self.address.to_string(),
-            last_updated_at: self.last_updated_at,
-        };
+        let wallet_info = self.as_ref().map(|wallet_info| WalletInfo {
+            balance: wallet_info.balance,
+            address: wallet_info.address.to_string(),
+            last_updated_at: wallet_info.last_updated_at,
+        });
 
         Event::json(&wallet_info).event("wallet")
     }

daemon/src/wallet_sync.rs

@@ -5,7 +5,7 @@ use tokio::sync::watch;
 use tokio::time::sleep;
 use xtra::Address;
 
-pub async fn new(wallet: Address<wallet::Actor>, sender: watch::Sender<WalletInfo>) {
+pub async fn new(wallet: Address<wallet::Actor>, sender: watch::Sender<Option<WalletInfo>>) {
     loop {
         sleep(Duration::from_secs(10)).await;
 
@@ -14,10 +14,10 @@ pub async fn new(wallet: Address<wallet::Actor>, sender: watch::Sender<WalletInf
             .await
             .expect("Wallet actor to be available")
         {
-            Ok(info) => info,
+            Ok(info) => Some(info),
             Err(e) => {
                 tracing::warn!("Failed to sync wallet: {:#}", e);
-                continue;
+                None
             }
         };