smartdata/ts/smartdata.classes.watcher.ts
2022-11-01 18:23:57 +01:00

34 lines
936 B
TypeScript

import { SmartDataDbDoc } from './smartdata.classes.doc.js';
import * as plugins from './smartdata.plugins.js';
/**
* a wrapper for the native mongodb cursor. Exposes better
*/
export class SmartdataDbWatcher<T = any> {
// STATIC
public readyDeferred = plugins.smartpromise.defer();
// INSTANCE
private changeStream: plugins.mongodb.ChangeStream<T>;
public changeSubject = new plugins.smartrx.rxjs.Subject<T>();
constructor(
changeStreamArg: plugins.mongodb.ChangeStream<T>,
smartdataDbDocArg: typeof SmartDataDbDoc
) {
this.changeStream = changeStreamArg;
this.changeStream.on('change', async (item: T) => {
this.changeSubject.next(
smartdataDbDocArg.createInstanceFromMongoDbNativeDoc(item) as any as T
);
});
plugins.smartdelay.delayFor(0).then(() => {
this.readyDeferred.resolve();
});
}
public async close() {
await this.changeStream.close();
}
}