Multi-file request support

[dotfortun3-code]

When uploading multiple files, an InvalidOperationException would occur when the request is forwarded. Copying the content to a MemoryStream first stops the exception from occurring.

Updated ToHttpContent helper function to copy files to a MemoryStream to prevent InvalidOperationException from occuring when multiple files are sent.

[twitchax]

Hey, sorry for the delay.

Can you add a passing / failing test that exercise this case, and the counter case?

[twitchax]

Hi @dotfortun3-code, I cannot repro this issue in the test. I have added more files to the CanProxyControllerPostWithFormAndFilesRequest test. Is there any way you can provide more context, or add a test that fails due to this issue?

[walterancona]

try to create an api with a multiform/form-data body in post, that accepts a IFormFileCollection in the body. You'll see instantly the problem.

[twitchax]

Ok, cool. I will try to get to this. If possible, it would be extremely helpful if you could add the test that would have failed, but is fixed by this PR, so that it remains covered.

[dotfortun3-code]

I can probably take a look at adding the test soon-ish. I just had a baby a few weeks ago so I've been a little tied up haha!

[twitchax]

Woohoo! Congrats!

[walterancona]

Congratulations!!! The problem is that the test passes, but in real cases the api gives back 200, but the files are not uploaded in the folder, so maybe this should be checked in the test. I've tried it but not succeeded.

[CosimoPiscopo]

@dotfortun3-code Congrats! I notice that the fix doesn't work with text/csv files. It seems like it doesn't read the file content. I fixed this by setting the position of the Memory Stream to the beginnig before creating the Stream Content:

ms.Seek(0, SeekOrigin.Begin);
var content = new StreamContent(ms);