public async Task evicts_handlers_after_timeout()
{
var createdHandlers = new List <HttpMessageHandler>();
HttpMessageHandler createHandler()
{
var handler =
new DelegateHandler((message, token) => Task.FromResult(new HttpResponseMessage()));
createdHandlers.Add(handler);
return(handler);
}
var factory = new RoundRobinHttpClientFactory(1, createHandler, TimeSpan.FromSeconds(5));
var clients = Enumerable.Range(0, 10).Select(i => factory.GetClient()).ToList();
clients.Count.ShouldBe(10);
createdHandlers.Count.ShouldBe(1);
await Task.Delay(TimeSpan.FromSeconds(6));
clients = Enumerable.Range(0, 10).Select(i => factory.GetClient()).ToList();
clients.Count.ShouldBe(10);
createdHandlers.Count.ShouldBe(2);
}
async Task CreateAndDisposeClientWithGarbageCollection(RoundRobinHttpClientFactory factory,
Func <HttpClient, Task> clientInvoker = null)
{
var client = factory.GetClient();
if (clientInvoker != null)
{
await clientInvoker(client);
}
client.Dispose();
}
public void creates_as_many_handlers_as_requested_count()
{
var createdHandlers = new List <HttpMessageHandler>();
HttpMessageHandler createHandler()
{
var handler =
new DelegateHandler((message, token) => Task.FromResult(new HttpResponseMessage()));
createdHandlers.Add(handler);
return(handler);
}
var factory = new RoundRobinHttpClientFactory(5, createHandler, Timeout.InfiniteTimeSpan);
var clients = Enumerable.Range(0, 10).Select(i => factory.GetClient()).ToList();
clients.Distinct().Count().ShouldBe(10);
createdHandlers.Count.ShouldBe(5);
}
public async Task evicts_503_handlers_temporarily()
{
var activeHandler = new DelegateHandler((message, token) => Task.FromResult(new HttpResponseMessage
{
StatusCode = HttpStatusCode.OK,
Content = new StringContent("active")
}));
int timedOut = 0;
var retryHandler = new DelegateHandler((message, token) =>
{
if (Interlocked.Exchange(ref timedOut, 1) == 0)
{
return(Task.FromResult(new HttpResponseMessage()
{
StatusCode = HttpStatusCode.ServiceUnavailable,
Headers = { RetryAfter = new RetryConditionHeaderValue(TimeSpan.FromSeconds(5)) }
}));
}
return(Task.FromResult(new HttpResponseMessage()
{
StatusCode = HttpStatusCode.OK,
Content = new StringContent("reactivated")
}));
});
var handlerIndex = 0;
var factory = new RoundRobinHttpClientFactory(2, () => handlerIndex++ *2 == 0 ? activeHandler : retryHandler);
var responsesBefore = await execute();
await Task.Delay(TimeSpan.FromSeconds(6));
var responsesAfter = await execute();
responsesBefore.Count(r => r.response.StatusCode == HttpStatusCode.ServiceUnavailable).ShouldBe(1);
responsesBefore.Any(r => r.content == "reactivated").ShouldBeFalse();
responsesAfter.All(r => r.response.StatusCode == HttpStatusCode.OK).ShouldBeTrue();
responsesAfter.Count(r => r.content == "reactivated").ShouldBe(5);
responsesAfter.Count(r => r.content == "active").ShouldBe(5);
async Task <List <(HttpResponseMessage response, string content)> > execute()
{
List <(HttpResponseMessage httpResponseMessage, string content)> response = new List <(HttpResponseMessage httpResponseMessage, string content)>();
for (int i = 0; i < 10; i++)
{
using (var client = factory.GetClient())
{
var httpResponseMessage = await client.SendAsync(new HttpRequestMessage(HttpMethod.Get, "http://nowhere.example/path"));
var content = httpResponseMessage.Content == null
? null
: await httpResponseMessage.Content?.ReadAsStringAsync();
response.Add((httpResponseMessage, content));
}
}
return(response);
}
}