Howto cancel async retries

[leozilla]

Can you add a short example howto cancel async retries.

I was surprised that canceling the returned CompletableFuture does not cancel the retries.
Am I using the library wrong or is this intended?
How do I cancel the retry in the following example, do I need to add a canceled flag and check this in the future method?

scheduler = Executors.newScheduledThreadPool(1);
executor = Executors.newCachedThreadPool();

CompletableFuture<Proxy> proxyFuture = Failsafe.with(proxyRetryPolicy)
                       .with(scheduler)
                       .future(asyncExecution -> {
                           return CompletableFuture.supplyAsync(proxySupplier, executor);
                       });

// does not cancel the retry .. keeps retrying
proxyFuture.cancel(false);
proxyFuture.cancel(true);

[jhalterman]

@leozilla Just pushed a fix for this. This issue has to do with performing an execution on via .future specifically where the resulting CompletableFuture cancellation was not propagated to the associated FailsafeFuture which would stop continued execution. Maybe you can give this a try and let me know if it resolves your problem. I pushed a test case here:

https://github.com/jhalterman/failsafe/blob/732746b013bb93f3d3d29ac3f026af19ef3cc532/src/test/java/net/jodah/failsafe/issues/Issue52.java#L36-L59

[leozilla]

Ah, thanks!
I did not expect this to be a bug otherwise I would have tried to fix it myself.
Anyway I try your fix now and let you know how it worked out.

[jhalterman]

You should be able to just pull master and mvn package to give it a try. Tnx.

[jhalterman]

Going to close this now ahead of the next release. @leozilla if the fix ends up not looking good on your end, feel free to re-open.

[jhalterman]

Released 0.9.3 with this fix.

[leozilla]

Sorry for the delay, it works for me.
Just one more minor thing.
The test ExecutionTest#shouldSupportMaxDuration() breaks randomly on windows with oracle jdk 1.8.0_91
Reason seems to be the Thread.sleep is exactly as long as the max duration.

Fails

public void shouldSupportMaxDuration() throws Exception {
    Execution exec = new Execution(new RetryPolicy().withMaxDuration(100, TimeUnit.MILLISECONDS));
    assertTrue(exec.canRetryOn(e));
    assertTrue(exec.canRetryOn(e));
    Thread.sleep(100); // <--
    assertFalse(exec.canRetryOn(e));
    assertTrue(exec.isComplete());
  }

Succeeds (although still a little ugly)

public void shouldSupportMaxDuration() throws Exception {
    Execution exec = new Execution(new RetryPolicy().withMaxDuration(100, TimeUnit.MILLISECONDS));
    assertTrue(exec.canRetryOn(e));
    assertTrue(exec.canRetryOn(e));
    Thread.sleep(105); // <--
    assertFalse(exec.canRetryOn(e));
    assertTrue(exec.isComplete());
  }

Should I provide a fix/PR for it?

[jhalterman]

Yea, that would be a good change. PR welcome :)