Introduce ActorName trait for better error messages

daemon/src/actor_name.rs

@@ -0,0 +1,3 @@
+pub trait ActorName {
+    fn actor_name() -> String;
+}

daemon/src/address_map.rs

@@ -3,6 +3,8 @@ use std::collections::HashMap;
 use std::hash::Hash;
 use xtra::{Address, Handler, Message};
 
+use crate::actor_name::ActorName;
+
 pub struct AddressMap<K, A> {
     inner: HashMap<K, xtra::Address<A>>,
 }
@@ -49,7 +51,7 @@ where
     pub async fn send<M>(&self, key: &K, msg: M) -> Result<(), NotConnected>
     where
         M: Message<Result = ()>,
-        A: Handler<M>,
+        A: Handler<M> + ActorName,
     {
         match self.inner.get(key) {
             Some(addr) if addr.is_connected() => {
@@ -58,14 +60,23 @@ where
                     .expect("we checked that we are connected");
                 Ok(())
             }
-            _ => Err(NotConnected),
+            _ => Err(NotConnected::new::<A>()),
         }
     }
 }
 
 #[derive(thiserror::Error, Debug)]
-#[error("Receiving actor is down")]
+#[error("{0} actor is down")]
-pub struct NotConnected;
+pub struct NotConnected(String);
+
+impl NotConnected {
+    pub fn new<A>() -> Self
+    where
+        A: ActorName,
+    {
+        NotConnected(A::actor_name())
+    }
+}
 
 /// A message to notify that an actor instance is stopping.
 pub struct Stopping<A> {

daemon/src/collab_settlement_taker.rs

@@ -1,3 +1,4 @@
+use crate::actor_name::ActorName;
 use crate::address_map::Stopping;
 use crate::model::cfd::{
     Cfd, CollaborativeSettlement, OrderId, SettlementKind, SettlementProposal,
@@ -192,3 +193,9 @@ impl Actor {
         self.complete(completed, ctx).await;
     }
 }
+
+impl ActorName for Actor {
+    fn actor_name() -> String {
+        "Taker collab settlement".to_string()
+    }
+}

daemon/src/lib.rs

@@ -21,6 +21,7 @@ use xtra::{Actor, Address};
 
 pub mod sqlx_ext; // Must come first because it is a macro.
 
+pub mod actor_name;
 pub mod actors;
 pub mod address_map;
 pub mod auth;

daemon/src/rollover_taker.rs

@@ -1,3 +1,4 @@
+use crate::actor_name::ActorName;
 use crate::address_map::Stopping;
 use crate::connection;
 use crate::model::cfd::{Cfd, Dlc, OrderId, Role, RollOverProposal, SettlementKind};
@@ -317,3 +318,9 @@ pub enum Completed {
 impl xtra::Message for Completed {
     type Result = Result<()>;
 }
+
+impl ActorName for Actor {
+    fn actor_name() -> String {
+        "Taker rollover".to_string()
+    }
+}

daemon/src/setup_maker.rs

@@ -1,3 +1,4 @@
+use crate::actor_name::ActorName;
 use crate::address_map::Stopping;
 use crate::model::cfd::{Cfd, CfdState, Dlc, Order, OrderId, Role};
 use crate::model::{Identity, Usd};
@@ -284,3 +285,9 @@ pub enum Completed {
 impl xtra::Message for Started {
     type Result = ();
 }
+
+impl ActorName for Actor {
+    fn actor_name() -> String {
+        "Taker contract setup".to_string()
+    }
+}