Interface ILoadWithCancellationAsync<TDestination>
- Namespace
- Wolfgang.Etl.Abstractions
- Assembly
- Wolfgang.Etl.Abstractions.dll
Defines an asynchronous loader interface for loading data of type T. A class implementing this interface is intended to be the last step in an ETL (Extract, Transform, Load) process.
public interface ILoadWithCancellationAsync<in TDestination> : ILoadAsync<TDestination> where TDestination : notnullType Parameters
TDestinationRepresents a single item to be sent to the destination of the ETL
- Inherited Members
Remarks
The loader is the last step in the ETL process and is responsible for saving data to the destination after processing. The loader is responsible for handling any exceptions that may occur during the loading process, including but not limited to communication errors, authentication errors, permission errors. The loader should be resilient and capable of retrying operations in case of transient failures. The loaded data is provided as an asynchronous stream of type TDestination, allowing for efficient writing of the data to the destination. Ideally, the loader should NOT do any transformation of the data; its sole responsibility is to save the data to the destination. However, occasionally, some minimal transformation may be necessary to ensure the data is in a suitable format for further processing. For example, if the data is being written to a CSV file, the same library that writes the CSV file may handle the conversion of objects of type TDestination to strings (rows). In this case, the pragmatic approach is to allow the loader to perform this minimal transformation.
Methods
LoadAsync(IAsyncEnumerable<TDestination>, CancellationToken)
Loads the data asynchronously.
Task LoadAsync(IAsyncEnumerable<in TDestination> items, CancellationToken token)Parameters
itemsIAsyncEnumerable<TDestination>The items to be loaded to the destination.
tokenCancellationTokenA CancellationToken to observe while waiting for the task to complete.
Returns
- Task
A task representing the asynchronous operation.
Remarks
The loader should be able to handle cancellation requests gracefully. If the caller doesn't plan on cancelling the loading, they can pass CancellationToken.None.