From a6a303f256e9feb8a638f5c30dd5d78e8bf23f8a Mon Sep 17 00:00:00 2001
From: Pablo Baleztena <pablo@ultharsoftware.com>
Date: Mon, 14 Oct 2024 09:55:39 -0300
Subject: [PATCH] [fabric/domain] Refactor EventStore interface and remove
 EventStream

---
 .../fabric/domain/src/events/event-store.ts   | 26 +++++++++++++------
 .../fabric/domain/src/events/event-stream.ts  | 16 ------------
 packages/fabric/domain/src/events/event.ts    |  5 ++++
 packages/fabric/domain/src/events/index.ts    |  1 -
 4 files changed, 23 insertions(+), 25 deletions(-)
 delete mode 100644 packages/fabric/domain/src/events/event-stream.ts

diff --git a/packages/fabric/domain/src/events/event-store.ts b/packages/fabric/domain/src/events/event-store.ts
index 0e31fc1..549031f 100644
--- a/packages/fabric/domain/src/events/event-store.ts
+++ b/packages/fabric/domain/src/events/event-store.ts
@@ -1,21 +1,31 @@
-import { AsyncResult, PosixDate } from "@fabric/core";
+import { AsyncResult, MaybePromise, PosixDate } from "@fabric/core";
 import { StoreQueryError } from "../errors/query-error.js";
-import { EventsFromStream, EventStream } from "./event-stream.js";
+import { UUID } from "../types/uuid.js";
+import { Event, EventFromKey } from "./event.js";
 import { StoredEvent } from "./stored-event.js";
 
-export interface EventStore<TEventStream extends EventStream> {
+export interface EventStore<TEvents extends Event> {
   /**
    * Store a new event in the event store.
    */
-  append<
-    TStreamKey extends TEventStream["name"],
-    T extends EventsFromStream<TEventStream, TStreamKey>,
-  >(
-    streamName: TStreamKey,
+  append<T extends TEvents>(
     event: T,
   ): AsyncResult<StoredEvent<T>, StoreQueryError>;
+
+  getEventsFromStream(
+    streamId: UUID,
+  ): AsyncResult<StoredEvent<TEvents>[], StoreQueryError>;
+
+  subscribe<TEventKey extends TEvents["type"]>(
+    events: TEventKey[],
+    subscriber: EventSubscriber<EventFromKey<TEvents, TEventKey>>,
+  ): void;
 }
 
+export type EventSubscriber<TEvents extends Event = Event> = (
+  event: StoredEvent<TEvents>,
+) => MaybePromise<void>;
+
 export interface EventFilterOptions {
   fromDate?: PosixDate;
   toDate?: PosixDate;
diff --git a/packages/fabric/domain/src/events/event-stream.ts b/packages/fabric/domain/src/events/event-stream.ts
deleted file mode 100644
index 9b70954..0000000
--- a/packages/fabric/domain/src/events/event-stream.ts
+++ /dev/null
@@ -1,16 +0,0 @@
-import { AsyncResult } from "@fabric/core";
-import { UUID } from "../types/uuid.js";
-import { Event } from "./event.js";
-import { StoredEvent } from "./stored-event.js";
-
-export interface EventStream<
-  TName extends string = string,
-  TEvent extends Event = Event,
-> {
-  id: UUID;
-  name: TName;
-  append<T extends TEvent>(event: Event): AsyncResult<StoredEvent<T>>;
-}
-
-export type EventsFromStream<T extends EventStream, TKey extends string> =
-  T extends EventStream<TKey, infer TEvent> ? TEvent : never;
diff --git a/packages/fabric/domain/src/events/event.ts b/packages/fabric/domain/src/events/event.ts
index e314103..d71ef0a 100644
--- a/packages/fabric/domain/src/events/event.ts
+++ b/packages/fabric/domain/src/events/event.ts
@@ -10,3 +10,8 @@ export interface Event<TTag extends string = string, TPayload = any> {
   readonly streamId: UUID;
   readonly payload: TPayload;
 }
+
+export type EventFromKey<
+  TEvents extends Event,
+  TKey extends TEvents["type"],
+> = Extract<TEvents, { type: TKey }>;
diff --git a/packages/fabric/domain/src/events/index.ts b/packages/fabric/domain/src/events/index.ts
index 7b181cc..a6fc9bd 100644
--- a/packages/fabric/domain/src/events/index.ts
+++ b/packages/fabric/domain/src/events/index.ts
@@ -1,4 +1,3 @@
 export * from "./event-store.js";
-export * from "./event-stream.js";
 export * from "./event.js";
 export * from "./stored-event.js";