public async Task BreakCircuitAndThrow()
{
var mockLogger = new Mock <ILogger>();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("Breaking circuit")))).Verifiable();
var pollyService = new PollyService(mockLogger.Object, 10);
for (int i = 0; i < 10; i++)
{
try
{
var posts = await pollyService.GetWithPolicy <string>(
PolicyTypes.CircuitBreaker,
async() =>
{
await Task.Delay(40);
throw new Exception("BOEM");
},
null).ConfigureAwait(false);
}
catch (Exception ex)
{
// expected
}
}
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("Breaking circuit"))), Times.AtLeast(1));
}
public async Task BreakCircuitRetryAndFinallyReturnFallbackData()
{
var mockLogger = new Mock <ILogger>();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("FallbackPolicy invoked")))).Verifiable();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("Breaking circuit")))).Verifiable();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked")))).Verifiable();
var pollyService = new PollyService(mockLogger.Object);
for (int i = 0; i < 10; i++)
{
try
{
var data = await pollyService.GetWithPolicy <string>(
PolicyTypes.CircuitBreakerWithRetryAndFallBack,
() => throw new Exception("BOEM"),
() => Task.FromResult("test")).ConfigureAwait(false);
data.Should().Be("test");
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("FallbackPolicy invoked"))), Times.AtLeastOnce());
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked"))), Times.Exactly(3));
}
catch (Exception ex)
{
// expected
}
}
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("Breaking circuit"))), Times.AtLeastOnce());
}
public async Task ReturnFallbackData()
{
var mockLogger = new Mock <ILogger>();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("FallbackPolicy invoked")))).Verifiable();
var pollyService = new PollyService(mockLogger.Object);
var result = await pollyService.GetWithPolicy <string>(PolicyTypes.Fallback,
() => throw new Exception("BOEM"),
() => Task.FromResult("test")
);
result.Should().Be("test");
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("FallbackPolicy invoked"))), Times.Exactly(1));
}
public void RetryThreeTimesBeforeThrowing()
{
var mockLogger = new Mock <ILogger>();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked")))).Verifiable();
var pollyService = new PollyService(mockLogger.Object);
var action = new Func <Task>(async() =>
await pollyService.GetWithPolicy <string>(PolicyTypes.Retry,
() => throw new Exception("BOEM"),
null
));
action.Should().Throw <Exception>().WithMessage("BOEM");
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked"))), Times.Exactly(3));
}
public async Task RetryThreeTimesAndReturnFallbackData()
{
var mockLogger = new Mock <ILogger>();
mockLogger.Setup(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked")))).Verifiable();
var pollyService = new PollyService(mockLogger.Object);
var data = await pollyService.GetWithPolicy <string>(
PolicyTypes.RetryWithFallBack,
() => throw new Exception("BOEM"),
() => Task.FromResult("test")).ConfigureAwait(false);
data.Should().Be("test");
mockLogger.Verify(x => x.Write(It.Is <string>(y => y.Equals("RetryPolicy invoked"))), Times.Exactly(3));
}
private const int FALLBACK_DELAY = 1; // 0 gives issues with json-server
public async Task GetAllPostsWithRetry()
{
try
{
_logger.Write(Program.SEPARATOR);
_logger.Write($"Getting all posts with retry");
var posts = await _pollyService.GetWithPolicy <IEnumerable <Post> >(
PolicyTypes.Retry,
() => _remoteApiService.GetAllPostsAsync(DELAY), null).ConfigureAwait(false);
_logger.Write($"result count: {posts.Count()}");
}
catch (Exception)
{
_logger.Write("Expected exception, timeout");
}
}
public void ThrowWhenFallbackIsNull(PolicyTypes type) => new Func <Task>(async() => await _pollyService.GetWithPolicy <string>(type, () => default(Task <string>), null)) .Should().Throw <ArgumentNullException>();