Represent channels and messages using a split "History" and "Snapshot" model.

This separates the code that figures out what happened to an entity from the code that represents it to a user, and makes it easier to compute a snapshot at a point in time (for things like bootstrap). It also makes the internal logic a bit easier to follow, since it's easier to tell whether you're working with a point in time or with the whole recorded history.

This hefty.

1 files changed, 50 insertions, 0 deletions

diff --git a/src/message/event.rs b/src/message/event.rs
new file mode 100644
index 0000000..bcc2238
--- /dev/null
+++ b/src/message/event.rs
@@ -0,0 +1,50 @@
+use super::{snapshot::Message, Id};
+use crate::{
+    channel::Channel,
+    event::{Instant, Sequenced},
+};
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
+pub struct Event {
+    #[serde(flatten)]
+    pub instant: Instant,
+    #[serde(flatten)]
+    pub kind: Kind,
+}
+
+impl Sequenced for Event {
+    fn instant(&self) -> Instant {
+        self.instant
+    }
+}
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum Kind {
+    Sent(Sent),
+    Deleted(Deleted),
+}
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
+pub struct Sent {
+    #[serde(flatten)]
+    pub message: Message,
+}
+
+impl From<Sent> for Kind {
+    fn from(event: Sent) -> Self {
+        Self::Sent(event)
+    }
+}
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize)]
+pub struct Deleted {
+    pub channel: Channel,
+    pub message: Id,
+}
+
+impl From<Deleted> for Kind {
+    fn from(event: Deleted) -> Self {
+        Self::Deleted(event)
+    }
+}