Use a two-tier hierarchy for events.

This will make it much easier to slot in new event types (login events!).

5 files changed, 33 insertions, 36 deletions

diff --git a/src/channel/event.rs b/src/channel/event.rs
index 9f2e263..f3dca3e 100644
--- a/src/channel/event.rs
+++ b/src/channel/event.rs
@@ -5,33 +5,30 @@ use crate::{
 };
 
 #[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
-pub struct Event {
-    #[serde(flatten)]
-    pub instant: Instant,
-    #[serde(flatten)]
-    pub kind: Kind,
+#[serde(tag = "event", rename_all = "snake_case")]
+pub enum Event {
+    Created(Created),
+    Deleted(Deleted),
 }
 
 impl Sequenced for Event {
     fn instant(&self) -> Instant {
-        self.instant
+        match self {
+            Self::Created(event) => event.instant,
+            Self::Deleted(event) => event.instant,
+        }
     }
 }
 
 #[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
-#[serde(tag = "type", rename_all = "snake_case")]
-pub enum Kind {
-    Created(Created),
-    Deleted(Deleted),
-}
-
-#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
 pub struct Created {
     #[serde(flatten)]
+    pub instant: Instant,
+    #[serde(flatten)]
     pub channel: Channel,
 }
 
-impl From<Created> for Kind {
+impl From<Created> for Event {
     fn from(event: Created) -> Self {
         Self::Created(event)
     }
@@ -39,10 +36,12 @@ impl From<Created> for Kind {
 
 #[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
 pub struct Deleted {
+    #[serde(flatten)]
+    pub instant: Instant,
     pub id: channel::Id,
 }
 
-impl From<Deleted> for Kind {
+impl From<Deleted> for Event {
     fn from(event: Deleted) -> Self {
         Self::Deleted(event)
     }
diff --git a/src/channel/history.rs b/src/channel/history.rs
index 0499927..78b3437 100644
--- a/src/channel/history.rs
+++ b/src/channel/history.rs
@@ -40,22 +40,20 @@ impl History {
     }
 
     fn created(&self) -> Event {
-        Event {
+        Created {
             instant: self.created,
-            kind: Created {
-                channel: self.channel.clone(),
-            }
-            .into(),
+            channel: self.channel.clone(),
         }
+        .into()
     }
 
     fn deleted(&self) -> Option<Event> {
-        self.deleted.map(|instant| Event {
-            instant,
-            kind: Deleted {
+        self.deleted.map(|instant| {
+            Deleted {
+                instant,
                 id: self.channel.id.clone(),
             }
-            .into(),
+            .into()
         })
     }
 }
diff --git a/src/channel/routes/test/on_create.rs b/src/channel/routes/test/on_create.rs
index ed49017..8c3c62b 100644
--- a/src/channel/routes/test/on_create.rs
+++ b/src/channel/routes/test/on_create.rs
@@ -2,7 +2,7 @@ use axum::extract::{Json, State};
 use futures::stream::StreamExt as _;
 
 use crate::{
-    channel::{app, routes},
+    channel::{self, app, routes},
     event,
     test::fixtures::{self, future::Immediately as _},
 };
@@ -53,8 +53,8 @@ async fn new_channel() {
         .expect("creation event published");
 
     assert!(matches!(
-        event.kind,
-        event::Kind::ChannelCreated(event)
+        event,
+        event::Event::Channel(channel::Event::Created(event))
             if event.channel == response_channel
     ));
 }
diff --git a/src/channel/routes/test/on_send.rs b/src/channel/routes/test/on_send.rs
index 3297093..d2acc48 100644
--- a/src/channel/routes/test/on_send.rs
+++ b/src/channel/routes/test/on_send.rs
@@ -4,8 +4,8 @@ use futures::stream::StreamExt;
 use crate::{
     channel,
     channel::routes,
-    event,
-    message::app::SendError,
+    event::{self, Sequenced},
+    message::{self, app::SendError},
     test::fixtures::{self, future::Immediately as _},
 };
 
@@ -53,10 +53,10 @@ async fn messages_in_order() {
     let events = events.collect::<Vec<_>>().immediately().await;
 
     for ((sent_at, message), event) in requests.into_iter().zip(events) {
-        assert_eq!(*sent_at, event.instant.at);
+        assert_eq!(*sent_at, event.at());
         assert!(matches!(
-            event.kind,
-            event::Kind::MessageSent(event)
+            event,
+            event::Event::Message(message::Event::Sent(event))
                 if event.message.sender == sender
                     && event.message.body == message
         ));
diff --git a/src/channel/snapshot.rs b/src/channel/snapshot.rs
index afef2fb..d4d1d27 100644
--- a/src/channel/snapshot.rs
+++ b/src/channel/snapshot.rs
@@ -1,5 +1,5 @@
 use super::{
-    event::{Created, Event, Kind},
+    event::{Created, Event},
     Id,
 };
 
@@ -11,9 +11,9 @@ pub struct Channel {
 
 impl Channel {
     fn apply(state: Option<Self>, event: Event) -> Option<Self> {
-        match (state, event.kind) {
-            (None, Kind::Created(event)) => Some(event.into()),
-            (Some(channel), Kind::Deleted(event)) if channel.id == event.id => None,
+        match (state, event) {
+            (None, Event::Created(event)) => Some(event.into()),
+            (Some(channel), Event::Deleted(event)) if channel.id == event.id => None,
             (state, event) => panic!("invalid channel event {event:#?} for state {state:#?}"),
         }
     }