@sv-kit/workerify/dist/expose.js

Headless Web Worker RPC: wrap(url), workerify(fn), expose(api). Abort, transferables, and typed proxies.

// packages/workerify/src/expose.ts
/// <reference lib="webworker" />
import { collectTransferables, toPlainError } from "./transfer";
/** 在 Worker 内调用：暴露一组方法给主线程调用 */
export function expose(api) {
    const controllers = new Map();
    self.onmessage = async (ev) => {
        const data = ev.data;
        if (!data || typeof data !== "object")
            return;
        if (data.type === "abort") {
            const c = controllers.get(data.id);
            if (c)
                c.abort(new DOMException("aborted", "AbortError"));
            return;
        }
        if (data.type !== "call")
            return;
        const { id, method, args } = data;
        const fn = api[method];
        const controller = new AbortController();
        controllers.set(id, controller);
        const reply = (msg, transfer) => self.postMessage(msg, { transfer });
        try {
            if (typeof fn !== "function") {
                throw new Error(`No such method: ${method}`);
            }
            const res = await fn(...args, { signal: controller.signal });
            // 自动挑选可转移
            const transfer = collectTransferables(res, 2);
            reply({ type: "result", id, ok: true, value: res }, transfer);
        }
        catch (err) {
            reply({ type: "result", id, ok: false, error: toPlainError(err) });
        }
        finally {
            controllers.delete(id);
        }
    };
}