Initialize NetworkCredentials in EmailConnectionInfo

[adriangutowski]

Fixes #90

[adriangutowski]

@nblumhardt,
could you take a look at my PR?

[nblumhardt]

Thanks for the PR! I'm not sure whether this change will prevent the use of default credentials in environments that depend on them - unfortunately I'm short of time to investigate.

Any other maintainers currently following this repo with some bandwidth? :-)

[adriangutowski]

@nblumhardt,
thank you for your prompt reply. I did some research into this - and apparently it should not be an issue. Take a look at this:
https://stackoverflow.com/a/14130274/7980221

If we are talking about the following null check, then you are right.

serilog-sinks-email/src/Serilog.Sinks.Email/Sinks/Email/EmailSink.cs

Lines 135 to 138 in 5fb82c6

	if (_connectionInfo.NetworkCredentials == null)
	smtpClient.UseDefaultCredentials = true;
	else
	smtpClient.Credentials = _connectionInfo.NetworkCredentials;

I need more time to investigate. I will get back to you as soon as I have the solution.

[adriangutowski]

@nblumhardt,
how about setting the default value for NetworkCredentials to CredentialCache.DefaultNetworkCredentials? Could you take a look at my latest commit (26a2d4e)?

[nblumhardt]

Sorry Adrian, I don't have any environment in which to test these things, so this has been sitting on my TODO list for a while. Can you share any details of what testing/investigation you've done? (E.g. why do you think this will preserve the existing behavior?)

Many thanks,
Nick

[nblumhardt]

Closing this one as stale, but thanks for sending the PR!