HTTP proxy tests

[the-thing]

Changes

• simple HTTP proxy server implementation (base on Netty)
• added tests for HTTP proxy with and without SSL
• some common session and SSL code refactored

Initially I wanted to open a follow up PR that adds support for explicit proxy auth method for proxy servers that do not support response challenge, but

1. I found out that it would require MINA change as well.
2. According to RFC proxy server should (although not MUST) challenge an invalid request, so for the time being lets assume that everybody uses compliant HTTP proxy server.

https://datatracker.ietf.org/doc/html/rfc7235#section-2.1

Likewise, upon receipt of a request that omits proxy credentials or contains invalid or partial proxy credentials, a proxy that requires authentication SHOULD generate a 407 (Proxy Authentication Required) response that contains a Proxy-Authenticate header field with at least one (possibly new) challenge applicable to the proxy.

[chrjohn]

@the-thing thank you, great addition to the test suite.

[the-thing]

@chrjohn I think I have seen this write error when using HTTP proxy (close exception or something).

[chrjohn]

Which write error? #1143 ??

[the-thing]

Yes, that's the one. I think I have seen it when I was running the new tests locally. Maybe this could something be used for testing?

[chrjohn]

You mean use the http proxy to provoke the WriteToClosedSessionException? Do you think #1143 is sensible?

[the-thing]

You mean use the http proxy to provoke the WriteToClosedSessionException?

Yes. Mostly for manual testing and debugging the problem, but maybe there can be some changes to capture exceptions for unit test cases to verify if this happens. Needs investigating.

Do you think #1143 is sensible?

It does look okish, but hold on for now. I might look at this is the upcoming days / weeks (not critical right?). Also org.apache.mina.core.write.WriteToClosedSessionException contains information about the request so might be worth logging it out what failed to write if not too long etc.

[chrjohn]

No need to rush, take your time. Thanks in advance!

Also org.apache.mina.core.write.WriteToClosedSessionException contains information about the request so might be worth logging it out what failed to write if not too long etc.

100% agree.