Add subscribe and publish utils

packages/net2/src/publish.ts

@@ -0,0 +1,46 @@
+import {EventEmitter} from "events"
+import {on} from "@welshman/lib"
+import {SignedEvent} from "@welshman/util"
+import {RelayMessage, isRelayOkMessage} from "./message.js"
+import {AbstractAdapter, AdapterEventType} from "./adapter.js"
+import {TypedEmitter} from "./util.js"
+
+export enum PublishEventType {
+  Ok = "publish:event:ok",
+}
+
+export type PublishEvents = {
+  [PublishEventType.Ok]: (id: string, ok: boolean, detail: string, url: string) => void
+}
+
+export class Publish extends (EventEmitter as new () => TypedEmitter<PublishEvents>) {
+  _unsubscriber: () => void
+
+  constructor(
+    readonly adapter: AbstractAdapter,
+    readonly event: SignedEvent,
+    readonly verb = "EVENT",
+  ) {
+    super()
+
+    this._unsubscriber = on(
+      adapter,
+      AdapterEventType.Receive,
+      (message: RelayMessage, url: string) => {
+        if (isRelayOkMessage(message)) {
+          const [_, id, ok, detail] = message
+
+          if (id === event.id) {
+            this.emit(PublishEventType.Ok, id, ok, detail, url)
+          }
+        }
+      },
+    )
+
+    adapter.send([verb, event])
+  }
+
+  close() {
+    this._unsubscriber()
+  }
+}