Urls in settings require a port

[DavidJohnWilliams]

Describe the bug

If you use the Urls setting and don't supply a port, when starting under ASP.Net Core you receive a timeout error.

The actual error is a NRE from this line:

WireMock.Net/src/WireMock.Net.Minimal/Owin/AspNetCoreSelfHost.cs

Line 152 in cbc28c2

if (originalScheme!.StartsWith("grpc", StringComparison.OrdinalIgnoreCase))

PortUtils.TryExtract has null annotations to say that the scheme out parameter will be null if TryExtract returns false, but there is a null-forgiving operator on the next line so you get a NRE.

Expected behavior:

Either no port is allowed and the code above should not run if TryExtract returns false; or the docs should be updated to explain that port is required on entries in Urls.

Test to reproduce

• 1 - Add a url to Urls without a port
• 2 - Start the server

Other related info

Side note: The exception thrown from Start is a timeout rather than the actual exception that occurred which made debugging the issue more difficult. It would be good to solve that as well.

BTW, I am happy to create a PR for this, but I'm raising the issue first for discussion.

[StefH]

@DavidJohnWilliams
Thank you.

---

My suggestion:

• throw ArgumentException if TryExtract returns false here
• also throw for this code PortUtils.TryExtract(addresses[i] ?
• if possible ; add unit test

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Side note: The exception thrown from Start is a timeout rather than the actual exception that occurred which made debugging the issue more difficult. It would be good to solve that as well.
--> make a new issue + PR for this one

[DavidJohnWilliams]

@StefH I have gone through the code a bit more in detail and I can see why you are suggesting to throw an exception there.

A couple of questions:

1. Why does PortUtils.TryExtract use a regex instead of Uri.TryCreate?

   If we used Uri.TryCreate and a port was not supplied then it defaults to the correct port based on scheme (or -1 e.g. for grpc). This could allow more granular control over when to throw the exception if a port is not supplied.

2. Regardless of the above should we actually throw an exception in HostUrlOptions.GetDetails or AspNetCoreSelfHost.SetHttpsAndUrls as that is what is used to setup listening. And if the parsing fails there will be no listeners setup anyway.

3. If you want to keep port as mandatory, should docs be updated with valid URL format?

[StefH]

1. Actually I don't know anymore, if you can replace it by Uri.TryCreate and all unit-tests pass, you can replace it.
2. Good point, I don't know. Maybe just log an warning?
3. Normally you would configure WireMock.Net to run on a specific port, so yes I need to check + update the docs. (Do you have a link to the docs where this should be updated?)

[DavidJohnWilliams]

The docs are here: https://wiremock.org/dotnet/settings/#urls, just a one liner.

I don't mind having to include port if it's in the docs. But at the same time, most commonly I would think it will either be port 80/443 for http/s. So having default ports seems reasonable to me, and fairly easy to implement / document.

If you supply a port it works, if you don't and it can be derived from the scheme default it works, if you don't and it can't be derived you get an error.

[DavidJohnWilliams]

Looks like custom parsing using the regex is required because sometimes wildcard urls like http://*:12345 are used.

I have created a PR with an example of what I was thinking about. It solves my proposed case, and should be backward compatible with existing setups as well.

If you don't like it, I'm also happy to go back to plan A.