chore(pegboard): cache actor kv info (#4617)

Author: NathanFlurry

engine/packages/pegboard/src/ops/actor/get_for_kv.rs

@@ -8,36 +8,51 @@ pub struct Input {
 	pub actor_id: Id,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Serialize, Deserialize)]
 pub struct Output {
 	pub name: String,
 	pub namespace_id: Id,
 }
 
-// TODO: Add cache (remember to purge cache when runner changes)
 #[operation]
 pub async fn pegboard_actor_get_for_kv(
 	ctx: &OperationCtx,
 	input: &Input,
 ) -> Result<Option<Output>> {
-	ctx.udb()?
-		.run(|tx| async move {
-			let tx = tx.with_subspace(keys::subspace());
-
-			let name_key = keys::actor::NameKey::new(input.actor_id);
-			let namespace_id_key = keys::actor::NamespaceIdKey::new(input.actor_id);
-
-			let (name_entry, namespace_id_entry) = tokio::try_join!(
-				tx.read_opt(&name_key, Serializable),
-				tx.read_opt(&namespace_id_key, Serializable),
-			)?;
-
-			let (Some(name), Some(namespace_id)) = (name_entry, namespace_id_entry) else {
-				return Ok(None);
-			};
-
-			Ok(Some(Output { name, namespace_id }))
+	ctx.cache()
+		.clone()
+		.request()
+		.fetch_one_json("actor.actor_get_for_kv", input.actor_id, {
+			move |mut cache, key| async move {
+				let output = ctx
+					.udb()?
+					.run(|tx| async move {
+						let tx = tx.with_subspace(keys::subspace());
+
+						let name_key = keys::actor::NameKey::new(input.actor_id);
+						let namespace_id_key = keys::actor::NamespaceIdKey::new(input.actor_id);
+
+						let (name_entry, namespace_id_entry) = tokio::try_join!(
+							tx.read_opt(&name_key, Serializable),
+							tx.read_opt(&namespace_id_key, Serializable),
+						)?;
+
+						let (Some(name), Some(namespace_id)) = (name_entry, namespace_id_entry)
+						else {
+							return Ok(None);
+						};
+
+						Ok(Some(Output { name, namespace_id }))
+					})
+					.custom_instrument(tracing::info_span!("actor_get_for_kv_tx"))
+					.await?;
+
+				if let Some(output) = output {
+					cache.resolve(&key, output);
+				}
+
+				Ok(cache)
+			}
 		})
-		.custom_instrument(tracing::info_span!("actor_get_for_kv_tx"))
 		.await
 }