Bug 41513 - NSUrlSession does not auto follow redirects
Summary: NSUrlSession does not auto follow redirects
Status: RESOLVED ANSWERED
Alias: None
Product: iOS
Classification: Xamarin
Component: Xamarin.iOS.dll ()
Version: XI 9.8 (tvOS / C7)
Hardware: PC Windows
: --- normal
Target Milestone: Future Cycle (TBD)
Assignee: Sebastien Pouliot
URL:
Depends on:
Blocks:
 
Reported: 2016-06-05 08:34 UTC by softlion
Modified: 2016-07-20 13:17 UTC (History)
5 users (show)

Tags:
Is this bug a regression?: ---
Last known good build:

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RESOLVED ANSWERED

Description softlion 2016-06-05 08:34:26 UTC
NSUrlSession should auto follow 302 calls.
Althoug HttpClient auto follow redirect is true (default), NSUrlSession does not follow 302.
Comment 2 softlion 2016-06-06 08:30:49 UTC
Well the problem is not with NSUrlSession, it is when i use HttpClient and in xamarin options i check "use NSUrlSession".

AUtoFollowHttpRedirect property is at true in my HttpClientHandler.
Comment 3 Rolf Bjarne Kvinge [MSFT] 2016-06-06 08:37:14 UTC
OK, that's a different problem that initially stated.
Comment 4 Sebastien Pouliot 2016-06-08 17:50:56 UTC
There is no `AUtoFollowHttpRedirect` property in HttpClientHandler, so I guess you likely mean `AllowAutoRedirect` or `HttpWebRequest.AllowAutoRedirect` (which is not related to HttpClient).

This should be handled by the underlying ModernHttpClient code [1] but I'll double check from an app.

[1] https://github.com/xamarin/ModernHttpClient/blob/master/src/ModernHttpClient/iOS/NSUrlSessionHandler.cs#L417
Comment 5 Sebastien Pouliot 2016-06-09 01:58:27 UTC
Unlike the other handlers, `NSUrlSessionHandler.AllowAutoRedirect` defaults to `false`. I'll fix this so it's easier to swap handlers without code changes.

However, once set to `true`, the handler did it's expected job. If you get different results please attach a self-contained test case to the bug report and we'll look into it again.


public Task<string> Get302 (HttpMessageHandler handler)
{
	var client = new HttpClient (handler);
	return Task.Run (async () => await client.GetStringAsync ("https://greenbytes.de/tech/tc/httpredirects/t302loc.asis"));
}

[Test]
public void NS302 ()
{
	var handler = new NSUrlSessionHandler ();
	handler.AllowAutoRedirect = true;
	var result = Get302 (handler);
	result.Wait ();
	Assert.That (result.Result, Contains.Substring ("You have reached the target"), "true");

	handler = new NSUrlSessionHandler ();
	handler.AllowAutoRedirect = false;
	result = Get302 (handler);
	try {
		result.Wait ();
	} catch (AggregateException ae) {
		var inner = ae.InnerException;
		Assert.That (inner is HttpRequestException, "HttpRequestException");
		Assert.That (inner.Message, Contains.Substring ("302 (Found)"), "302");
	}
}
Comment 6 Sebastien Pouliot 2016-06-09 13:37:15 UTC
> Unlike the other handlers, `NSUrlSessionHandler.AllowAutoRedirect` defaults to `false`. 
> I'll fix this so it's easier to swap handlers without code changes.

^ now tracked in #41656
Comment 7 Vincent Dondain [MSFT] 2016-07-20 13:17:49 UTC
Sebastien seems to have addressed the issue in comment5 and bug #41656 is now fixed.

If you are still experiencing this issue please provide all the requested information 
and re-open the bug report. Thanks!