json-crdt-repo/lib/pubsub/index.js

JSON CRDT server and syncing local-first browser client

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.pubsub = exports.PubSubBC = exports.PubSubM = void 0;
const rxjs_1 = require("rxjs");
class PubSubM {
    constructor() {
        this.bus$ = new rxjs_1.Subject();
    }
    pub(msg) {
        this.bus$.next(msg);
    }
    end() {
        this.bus$.complete();
    }
}
exports.PubSubM = PubSubM;
class PubSubBC extends PubSubM {
    constructor(bus) {
        super();
        this.bus = bus;
        const ch = (this.ch = new BroadcastChannel(bus));
        ch.onmessage = (e) => this.bus$.next(e.data);
    }
    pub(msg) {
        this.ch.postMessage(msg);
        super.pub(msg);
    }
    end() {
        this.ch.close();
        super.end();
    }
}
exports.PubSubBC = PubSubBC;
/** Cache of global in-memory pubsub instances. */
const memoryCache = {};
/**
 * Creates new cross-tab pubsub broadcast channel. Own messages are also received.
 *
 * @param bus The name of the broadcast bus, where messages will be published.
 * @returns A PubSub instance that publishes messages to the specified bus.
 */
const pubsub = (bus) => typeof BroadcastChannel !== 'undefined'
    ? new PubSubBC(bus)
    : memoryCache[bus] || (memoryCache[bus] = new PubSubM());
exports.pubsub = pubsub;