Help with JazzOAuthClient

[forsmann]

Hello,
I'm trying to use JazzRootServicesHelper. I'm getting this error: Unable to access the Jazz rootservices document at:

However, when i put the url in the browser i get the rdf file. It's an https site. I put this in the code:

            ServicePointManager.ServerCertificateValidationCallback +=
                (sender, cert, chain, sslPolicyErrors) => true;

Any ideas?

[berezovskyi]

Hi @forsmann,

The message you specified should be printed on RootServicesException re exception. What message does it come with and what is its nested exception?

You disable cert validation, does it mean your server has a self-signed TLS cert? Does your code work if you fetch rootservices from https://oslc.itm.kth.se/ccm? Please note that the library appends /rootservices on its own. Also, the way you disable cert validation is a bit different from passing a lambda to the oslc4net client, did you make sure your delegate gets called in the process?

I am assuming you are on .NET Framework (4.8?) due to Jazz project not having been ported to .NET 6+ yet. What version of the OSLC4Net.Client are you using? 0.3.0-alpha?

On a side note, only https://github.com/OSLC/oslc4net/blob/main/OSLC4Net_NETFramework/OSLC4Net.Client.Jazz/Oslc/Jazz/JazzOAuthClient.cs requires .NET Framework. I am thinking to split OSLC4Net.Client.Jazz into:

• OSLC4Net.Client.Jazz that will be .NET 6+ compatible and have all the code except for https://github.com/OSLC/oslc4net/blob/main/OSLC4Net_NETFramework/OSLC4Net.Client.Jazz/Oslc/Jazz/JazzOAuthClient.cs, and
• OSLC4Net.Client.Jazz.OAuth10a that will only contain the https://github.com/OSLC/oslc4net/blob/main/OSLC4Net_NETFramework/OSLC4Net.Client.Jazz/Oslc/Jazz/JazzOAuthClient.cs class. It will remain to be .NET Framework dependent because DotNetOpenAuth only targets .NET Framework and I am not planning to fork&port it to .NET 6+ because it's using an obsolete OAuth1.0a mechanism.

This should make Jazz client usable in .NET 6+, esp. if you rely on Jazz Forms auth (OIDC support is not yet part of oslc4net).

[berezovskyi]

And to be clear, OSLC4Net.Client.Jazz will not work under .NET (Core) 3.1 because .NET 3.1 is newer than .NET Framework 4.8. More on this under https://en.wikipedia.org/wiki/.NET#History. Everything under https://github.com/OSLC/oslc4net/tree/main/OSLC4Net_SDK except for test projects targets netstandard2.0 and will run on any reasonably modern dotnet, whether .net framework 4.8, or mono, or .net core 3.1 (don't use it in prod, it does not get security updates), or (best) under dotnet6 or dotnet8.

[forsmann]

I think I was headed down the wrong path. I would like to use .net core if possible. I see that OSLC4net_SDK should work. I just didn't see an example of how to use OAuth and get root services using this. Maybe you can help.

[berezovskyi]

A few points:

• There is no need to have OAuth to get OSLC root services. The root services document includes bootstrap information, possibly for oauth endpoints, and thus shall be accessible without auth.
• To get the root services document, you should use https://github.com/OSLC/oslc4net/blob/main/OSLC4Net_NETFramework/OSLC4Net.Client.Jazz/Oslc/Jazz/JazzRootServicesHelper.cs For now, that class is located in the project that only targets legacy .NET Framework / Mono. We would need to split the OAuth out of that project to make JazzRootServicesHelper directly usable in .net core.
• There is no way to support OAuth1.0a oslc4net code in .net core because that code depends on https://www.nuget.org/packages/DotNetOpenAuth.OAuth.Consumer/4.3.4.13329#supportedframeworks-body-tab and it does not support .net core. Possible solutions (from simplest to ):
  • use Jazz Forms auth
  • use OAuth 2 / OIDC (using RestSharp or only via ASP.NET Core as shown in https://github.com/magnusstuhr/httpclient-seamless-openid-oauth2/tree/main )
  • rewrite the OAuth1.0a code in oslc4net to use RestSharp that provides OAuth 1 and 2 clients: https://restsharp.dev/authenticators.html#oauth1 – I will be happy to review and merge the PR if you are ready to help out with this
  • fork DotNetOpenAuth.OAuth.Consumer and port that code to netstandard2.0 or net6.0+ (questionable from security POV, that library is dead for at least 7 10 years).

[berezovskyi]

What OSLC application are you integrating with? Is it IBM Jazz?

[forsmann]

IBM DOORS. I just got the Dot Net framework version building in Mono. Going to try it.