feat: worker-relay pkg

packages/worker-relay/src/interface.ts

@@ -0,0 +1,63 @@
+import debug from "debug";
+import { NostrEvent, ReqCommand, WorkerMessage } from "./types";
+import { v4 as uuid } from "uuid";
+
+export class WorkerRelayInterface {
+  #worker: Worker;
+  #log = (msg: any) => console.debug(msg);
+  #commandQueue: Map<string, (v: unknown) => void> = new Map();
+
+  constructor(path: string) {
+    this.#log(`Module path: ${path}`);
+    this.#worker = new Worker(path, { type: "module" });
+    this.#worker.onmessage = e => {
+      const cmd = e.data as WorkerMessage<any>;
+      if (cmd.cmd === "reply") {
+        const q = this.#commandQueue.get(cmd.id);
+        q?.(cmd);
+        this.#commandQueue.delete(cmd.id);
+      }
+    };
+  }
+
+  async init() {
+    return await this.#workerRpc<void, boolean>("init");
+  }
+
+  async open() {
+    return await this.#workerRpc<void, boolean>("open");
+  }
+
+  async migrate() {
+    return await this.#workerRpc<void, boolean>("migrate");
+  }
+
+  async event(ev: NostrEvent) {
+    return await this.#workerRpc<NostrEvent, boolean>("event", ev);
+  }
+
+  async req(req: ReqCommand) {
+    return await this.#workerRpc<ReqCommand, Array<NostrEvent>>("req", req);
+  }
+
+  #workerRpc<T, R>(cmd: string, args?: T, timeout = 5_000) {
+    const id = uuid();
+    const msg = {
+      id,
+      cmd,
+      args,
+    } as WorkerMessage<T>;
+    this.#worker.postMessage(msg);
+    return new Promise<R>((resolve, reject) => {
+      let t: ReturnType<typeof setTimeout>;
+      this.#commandQueue.set(id, v => {
+        clearTimeout(t);
+        const cmdReply = v as WorkerMessage<R>;
+        resolve(cmdReply.args);
+      });
+      t = setTimeout(() => {
+        reject("timeout");
+      }, timeout);
+    });
+  }
+}