What is the "elegant" method of using BackOffPolicy

Question

I sometimes noticed that my SDK calls on my computer periodically interrupted with a 500 error, retrying the request usually fixes the error immediately. Looking at the Google documentation, it is recommended to use an exponential return technique, I wrote my own implementation that works fine, however, during debugging, I accidentally ran into the BackOffPolicy interface, with a lot of research, I even found an implementation of ExponentialBackOffPolicy.

So instead of managing it myself, I decided to better remove my implementation and let the SDK do it for me. The delay policy (according to my information) can be configured using the built-in HTTP request, so it is quite easy to use it when creating requests manually or when using batch requests, however I cannot find the easiest place to enter this value when using the main SDK, for example if I want to set a deferral policy for:

drive.files().get(id).execute(); 

I can not do something like:

 drive.files().get(id) .setBackOffPolicy(new ExponentialBackOffPolicy()) .execute(); 

I would need to do this:

 drive.files().get(id) .buildHttpRequest() .setBackOffPolicy(new ExponentialBackOffPolicy()) .execute(); 

However, if I do this, I will also need to reproduce the syntax logic of the execute method from Drive.Files.Get and convert the result to a File object, which is obviously not an ideal approach. Is there an easier way to “add” this as a whole to the request, or perhaps specify a way to override the default policy for all requests?

If not, maybe this could be introduced in a future version of the Drive SDK?

Thanks David

Answer 1

AFAIK Google, made by Exponential Backoff, is used only when loading or downloading content in the Java interface of the drive. For other queries, you need your own implementation.

What I did to implement it for any request was to complete Callable after the request and let the wrapper class handle exceptions and retry the request.

Answer 2

The Google Drive SDK documentation includes an example showing how to correctly implement exponential deferral using the Drive API:

https://developers.google.com/drive/handle-errors

Answer 3

The code for exponential delay is used here:

 boolean thisIsARetry = false; boolean keepRetrying = true; int delayTime = 2; int maxDelayTime = 4; while(keepRetrying && delayTime <= maxDelayTime) { if(thisIsARetry) { //sleep for delayTime seconds try { Thread.sleep(1000 * delayTime); delayTime *= 2; } catch (Exception e) { //print exception delayTime *= 2; continue; } } else { thisIsARetry = true; } //the actual network request or some other operation here if(ACTUAL_OPERATION_SUCCESS) { keepRetrying = false; } }