Today I had the brilliant idea of building a presence logger for Skype for Business. I wanted to do preliminary research to see how viable this idea would be. Reading through the Skype documentation, it seemed like there is a nice Web SDK that can be used to build a simple application. Unfortunately, I was not able to get past the authentication phase. I presume that this was because of the CORS restriction. For any development with the UCWA server, the requesting domain needs to be specifically authorized. Since I don't have this access and don't have a way to authorize the domain, I have paused my research until I can get a hold of the test server. I wanted to capture the research I have done with some useful links. Total time spent on this research 3.5 hours.
Notes
Playing with Postman to get responses from the server, obtained a URL with /PassiveAuth/PassiveAuth.aspx
when attempted to perform a POST to the endpoint WebTicket/oauthtoken
with form-ended input ```
[{"key":"grant_type","value":"urn:microsoft.rtc:passive","description":"","type":"text","enabled":true}]
Just while I was typing this out, I realized I was authenticating with the wrong credentials. I was using the wrong domain. Such is the power of writing things down. I was able to get an access token making a direct call to the REST API via Postman, however, the web SDK got stuck. This could be because I'm running a basic non-async python server or because of CORS related issues when the request is made via the browser adding originating errors.
Sadly this came to an end as I could not get a response from the server following this guide after step 7. This was because the originating host is not whitelisted as described here.
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Conclusion
The required API for building this kind of API is the UCWA API. In order to use it, the requesting server URL, that is passed via the X-Ms-Origin
header needs to be set up on the Lync/UCWA server.
Links
- https://www.matthewproctor.com/skype-web-sdk-creating-a-presence-dashboard
- https://www.matthewproctor.com/pluralsight-skype-web-sdk-getting-started
- https://github.com/OfficeDev/skype-web-sdk-samples/issues/9
- https://www.reddit.com/r/skype4b/comments/5d6z6l/skype_for_business_web_passive_authentication/
- https://blog.thoughtstuff.co.uk/2018/07/skype-for-business-server-2019-preparation-for-developers/