rxdb/src/plugins/electron/rx-storage-ipc-renderer.ts

A local-first realtime NoSQL Database for JavaScript applications - https://rxdb.info/

import { Subject } from 'rxjs';
import {
    getRxStorageRemote,
    RxStorageRemote,
    RxStorageRemoteSettings,
    MessageFromRemote
} from '../storage-remote/index.ts';
import {
    IPC_RENDERER_KEY_PREFIX
} from './electron-helper.ts';
import { PROMISE_RESOLVE_VOID } from '../utils/index.ts';

export type RxStorageIpcRendererSettings = {
    /**
     * Set the same key on both sides
     * to ensure that messages do not get mixed
     * up when you use more then one storage.
     */
    key: string;
    ipcRenderer: any;
    mode: RxStorageRemoteSettings['mode'];
};

export type RxStorageIpcRenderer = RxStorageRemote;
export function getRxStorageIpcRenderer(
    settings: RxStorageIpcRendererSettings
): RxStorageIpcRenderer {
    const channelId = [
        IPC_RENDERER_KEY_PREFIX,
        settings.key
    ].join('|');

    const storage = getRxStorageRemote({
        identifier: 'electron-ipc-renderer',
        mode: settings.mode,
        messageChannelCreator() {
            const messages$ = new Subject<MessageFromRemote>();
            const listener = (_event: any, message: any) => {
                messages$.next(message);
            };
            settings.ipcRenderer.on(channelId, listener);
            settings.ipcRenderer.postMessage(
                channelId,
                false
            );
            return Promise.resolve({
                messages$,
                send(msg) {
                    settings.ipcRenderer.postMessage(
                        channelId,
                        msg
                    );
                },
                close() {
                    settings.ipcRenderer.removeListener(channelId, listener);
                    return PROMISE_RESOLVE_VOID;
                }
            });
        },
    });
    return storage;
}