Polly's Policy.TimeoutAsync does not work with PolicyWrap in an async context

Question

This is a FULLY working example (Copy/paste it and play around, just get the Polly Nuget)

I have the following Console app code which makes a POST request to an HTTP cli

Answer 1

Polly Timeout policy with the default TimeoutStrategy.Optimistic operates by timing-out CancellationToken, so the delegates you execute must respond to co-operative cancellation. See the Polly Timeout wiki for more detail.

Changing your execution line to the following should make the timeout work:

var response = await Policies.PolicyWrap.ExecuteAsync(
    async ct => await _httpClient.PostAsync(/* uri */, new StringContent(request), ct).ConfigureAwait(false), 
    CancellationToken.None // CancellationToken.None here indicates you have no independent cancellation control you wish to add to the cancellation provided by TimeoutPolicy. You can also pass in your own independent CancellationToken.
);

Polly async executions by default do not continue on captured synchronization context (they execute with .ConfigureAwait(false)), so this can also be shortened to:

var response = await Policies.PolicyWrap.ExecuteAsync(
    ct => _httpClient.PostAsync(/* uri */, new StringContent(request), ct), 
    CancellationToken.None
);