Introduce drop-in replacement for tokio::spawn that logs errors

Otherwise, any errors occurring within these tasks are silently
ignored.

daemon/src/maker.rs

@@ -42,6 +42,7 @@ mod seed;
 mod send_to_socket;
 mod setup_contract;
 mod to_sse_event;
+mod tokio_ext;
 mod wallet;
 mod wallet_sync;
 mod wire;

daemon/src/oracle.rs

@@ -1,6 +1,7 @@
 use crate::actors::log_error;
 use crate::model::cfd::{Cfd, CfdState};
 use crate::model::BitMexPriceEventId;
+use crate::tokio_ext;
 use anyhow::{Context, Result};
 use async_trait::async_trait;
 use cfd_protocol::secp256k1_zkp::{schnorrsig, SecretKey};
@@ -111,7 +112,7 @@ where
 
         for event_id in self.pending_announcements.iter().cloned() {
             let this = this.clone();
-            tokio::spawn(async move {
+            tokio_ext::spawn_fallible(async move {
                 let url = event_id.to_olivia_url();
 
                 tracing::debug!("Fetching announcement for {}", event_id);

daemon/src/taker.rs

@@ -42,6 +42,7 @@ mod send_to_socket;
 mod setup_contract;
 mod taker_cfd;
 mod to_sse_event;
+mod tokio_ext;
 mod wallet;
 mod wallet_sync;
 mod wire;

daemon/src/tokio_ext.rs

@@ -0,0 +1,14 @@
+use std::fmt;
+use std::future::Future;
+
+pub fn spawn_fallible<F, E>(future: F)
+where
+    F: Future<Output = Result<(), E>> + Send + 'static,
+    E: fmt::Display,
+{
+    tokio::spawn(async move {
+        if let Err(e) = future.await {
+            tracing::warn!("Task failed: {:#}", e);
+        }
+    });
+}