Function next

src/cursor/abstract_cursor.ts:554–581

Get the next available document from the cursor, returns null if no more documents are available.

()

  /** Get the next available document from the cursor, returns null if no more documents are available. */
  async next(): Promise<TSchema | null> {
    this.signal?.throwIfAborted();

    if (this.cursorId === Long.ZERO) {
      throw new MongoCursorExhaustedError();
    }

    if (this.cursorOptions.timeoutMode === CursorTimeoutMode.ITERATION && this.cursorId != null) {
      this.timeoutContext?.refresh();
    }

    try {
      do {
        const doc = this.documents?.shift(this.deserializationOptions);
        if (doc != null) {
          if (this.transform != null) return await this.transformDocument(doc);
          return doc;
        }
        await this.fetchBatch();
      } while (!this.isDead || (this.documents?.length ?? 0) !== 0);
    } finally {
      if (this.cursorOptions.timeoutMode === CursorTimeoutMode.ITERATION) {
        this.timeoutContext?.clear();
      }
    }

    return null;
  }

  /**
   * Try to get the next available document from the cursor or `null` if an empty batch is returned