smartdata/ts/smartdata.classes.cursor.ts

import * as plugins from './smartdata.plugins';

/**
 * a wrapper for the native mongodb cursor. Exposes better 
 */
export class SmartdataDbCursor<T = any> {
  // STATIC

  // INSTANCE
  public mongodbCursor: plugins.mongodb.FindCursor<T>;
  constructor(cursorArg: plugins.mongodb.FindCursor<T>) {
    this.mongodbCursor = cursorArg
  };

  public async next(closeAtEnd = true) {
    const result = await this.mongodbCursor.next();
    if (!result && closeAtEnd) {
      await this.close();
    };
    return result;
  };

  public async forEach(forEachFuncArg: (itemArg: T) => Promise<any>, closeCursorAtEnd = true) {
    let currentValue: T;
    do {
      currentValue = await this.mongodbCursor.next();
      if (currentValue) {
        await forEachFuncArg(currentValue);
      }
    } while (currentValue);
    if (closeCursorAtEnd) {
      await this.close();
    }
  }

  public async close() {
    await this.mongodbCursor.close();
  }
}