Bug 44978 - HttpClientHandler.SendAsync should throw HttpRequestException for proxy auth failure
Summary: HttpClientHandler.SendAsync should throw HttpRequestException for proxy auth ...
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Net.Http ()
Version: 4.8.0 (C9)
Hardware: PC Mac OS
: --- normal
Target Milestone: Untriaged
Assignee: Marek Safar
Depends on: 19594
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Reported: 2016-10-03 14:21 UTC by Matt Ward
Modified: 2016-10-06 10:17 UTC (History)
1 user (show)

Is this bug a regression?: No
Last known good build:

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Description Matt Ward 2016-10-03 14:21:28 UTC
NuGet v3 fails to request proxy credentials in Mono because the HttpClient's HttpClientHandler throws a WebException instead of throwing a HttpRequestException with the WebException set as its InnerException.

On Windows a HttpRequestException is thrown with the error message: "An error occurred while sending the request." and the WebException is set as the HttpRequestException's InnerException.

Tests for this problem are available from the following GitHub repository:


NuGet v3.4.4 (unpatched for Mono) catches the HttpRequestException here:


NuGet v3.5 has been patched for Mono with the following commit which checks that the exception thrown is a WebException:

Comment 1 Marek Safar 2016-10-05 15:59:06 UTC
Fixed in master and 4.8 branch
Comment 2 Matt Ward 2016-10-06 10:17:33 UTC
This fix looks good to me.

There seems to be another different problem where credentials for the proxy are not accepted for https package sources. Package sources that use http are OK. Mono 4.4.1 is also OK. I will look into this other problem and open a new bug with a test repro.