Ejemplo n.º 1
0
        public async Task Should_honour_cancellation_even_if_prior_execution_has_cached()
        {
            const string valueToReturn = "valueToReturn";
            const string executionKey  = "SomeExecutionKey";

            CachePolicy cache = Policy.CacheAsync(new StubCacheProvider(), TimeSpan.MaxValue);

            CancellationTokenSource tokenSource = new CancellationTokenSource();

            int delegateInvocations = 0;
            Func <CancellationToken, Task <string> > func = async ct =>
            {
                // delegate does not observe cancellation token; test is whether CacheEngine does.
                delegateInvocations++;
                await TaskHelper.EmptyTask.ConfigureAwait(false);

                return(valueToReturn);
            };

            (await cache.ExecuteAsync(func, new Context(executionKey), tokenSource.Token).ConfigureAwait(false)).Should().Be(valueToReturn);
            delegateInvocations.Should().Be(1);

            tokenSource.Cancel();

            cache.Awaiting(policy => policy.ExecuteAsync(func, new Context(executionKey), tokenSource.Token))
            .ShouldThrow <OperationCanceledException>();
            delegateInvocations.Should().Be(1);
        }
Ejemplo n.º 2
0
        public async Task Should_honour_cancellation_during_delegate_execution_and_not_put_to_cache()
        {
            const string valueToReturn = "valueToReturn";
            const string executionKey  = "SomeExecutionKey";

            IAsyncCacheProvider stubCacheProvider = new StubCacheProvider();
            CachePolicy         cache             = Policy.CacheAsync(stubCacheProvider, TimeSpan.MaxValue);

            CancellationTokenSource tokenSource = new CancellationTokenSource();

            Func <CancellationToken, Task <string> > func = async ct =>
            {
                tokenSource.Cancel(); // simulate cancellation raised during delegate execution
                ct.ThrowIfCancellationRequested();
                await TaskHelper.EmptyTask.ConfigureAwait(false);

                return(valueToReturn);
            };

            cache.Awaiting(policy => policy.ExecuteAsync(func, new Context(executionKey), tokenSource.Token))
            .ShouldThrow <OperationCanceledException>();

            ((string)await stubCacheProvider.GetAsync(executionKey, CancellationToken.None, false).ConfigureAwait(false)).Should().BeNull();
        }