Retrying the request using Retrofit 2

Question

How can I add retry functionality to the requests sent by Retrofit 2 library. Something like:

service.listItems().enqueue(new Callback>         


        

Answer 1

I did something quite similar to Ashkan Sarlak, but since Retrofit 2.1 passes the Call into the onFailure method, you can simplify to one CallbackWithRetry abstract class. See:

public abstract class CallbackWithRetry implements Callback {



 private static final String TAG = "CallbackWithRetry";

  private int retryCount = 0;

  private final Logger logger;
  private final String requestName;
  private final int retryAttempts;

  protected CallbackWithRetry(@NonNull Logger logger, @NonNull String requestName, int retryAttempts) {
    this.logger = logger;
    this.requestName = requestName;
    this.retryAttempts = retryAttempts;
  }

  @Override
  public void onFailure(Call call, Throwable t) {
    if (retryCount < retryAttempts) {
      logger.e(TAG, "Retrying ", requestName, "... (", retryCount, " out of ", retryAttempts, ")");
      retry(call);

      retryCount += 1;
    } else {
      logger.e(TAG, "Failed request ", requestName, " after ", retryAttempts, " attempts");
    }
  }

  private void retry(Call call) {
    call.clone().enqueue(this);
  }
}