web-worker-helper/dist/esm/worker-farm/worker-body.js

Utilities for running tasks on worker threads

import { getTransferList } from '../utils/worker-utils/get-transfer-list';
var onMessageWrapperMap = new Map();
/**
 * Type safe wrapper for worker code
 */
var WorkerBody = /** @class */ (function () {
    function WorkerBody() {
    }
    Object.defineProperty(WorkerBody, "onmessage", {
        /*
         * (type: WorkerMessageType, payload: WorkerMessagePayload) => any
         */
        set: function (onMessage) {
            self.onmessage = function (message) {
                if (!isKnownMessage(message)) {
                    return;
                }
                // Confusingly the message itself also has a 'type' field which is always set to 'message'
                var _a = message.data, type = _a.type, payload = _a.payload;
                onMessage(type, payload);
            };
        },
        enumerable: false,
        configurable: true
    });
    WorkerBody.addEventListener = function (onMessage) {
        var onMessageWrapper = onMessageWrapperMap.get(onMessage);
        if (!onMessageWrapper) {
            onMessageWrapper = function (message) {
                if (!isKnownMessage(message)) {
                    return;
                }
                // Confusingly the message itself also has a 'type' field which is always set to 'message'
                var _a = message.data, type = _a.type, payload = _a.payload;
                onMessage(type, payload);
            };
        }
        self.addEventListener('message', onMessageWrapper);
    };
    WorkerBody.removeEventListener = function (onMessage) {
        var onMessageWrapper = onMessageWrapperMap.get(onMessage);
        onMessageWrapperMap.delete(onMessage);
        self.removeEventListener('message', onMessageWrapper);
    };
    /**
     * Send a message from a worker to creating thread (main thread)
     * 从 worker 线程发送消息到主线程
     * @param type
     * @param payload
     */
    WorkerBody.postMessage = function (type, payload) {
        if (self) {
            var data = { source: 'Worker thread', type: type, payload: payload };
            var transferList = getTransferList(payload);
            // TODO: targetOrigin, transferList
            // eslint-disable-next-line @typescript-eslint/ban-ts-comment
            // @ts-ignore
            self.postMessage(data, transferList);
        }
    };
    return WorkerBody;
}());
export default WorkerBody;
// Filter out noise messages sent to workers
function isKnownMessage(message) {
    var type = message.type, data = message.data;
    return type === 'message' && data && typeof data.source === 'string' && data.source === 'Main thread';
}