Hi Olek,
Disclaimer: I'm not an expert so am just speaking from my experience so far:
API Apps now have the social media login stuff. The top requested feature is 1st class support for custom authentication as well. Currently it seems there is no support to modify the social media login experience - this means you cannot add your
own claims - such as your own app user id. MS are blurring mobile app and api app and web app together into some funky mixed product. I imagine, in reality, mobile apps will be removed eventually and api apps will have a more dynamic set-up, meaning
you can add that funky table access stuff in Mobile Services if you choose to.
Yes you can use them all from javascript. Here is a link for you that you will need, and the most important snippet:https://azure.microsoft.com/en-gb/blog/announcing-app-service-authentication-authorization/
"Your application can trigger the same redirect itself by navigating the user to the /.auth/login/<provider> endpoint of your site, where
<provider> is one of aad, facebook, google, microsoftaccount, and twitter."
and
"submit an HTTP POST to the same endpoint with the provider token in a JSON body under the key “access_token” (or “authenticationToken” for Microsoft Account)"
HOWEVER - this doesn't work fully, because the gateway that the new app service sits behind generates CORS errors even when everything is fully configured and working correctly.
I don't know about .Net Core, though the rest is perfectly fine and compatible.
Doing swagger is trivial. Find the Nuget package, install it and you're almost done already. There are documents online about this - it's all very straight forward.
I would like to give a summary though. DO NOT USE the new app service mobile apps and api apps yet. They are very pre-release and you will run into a lot of problems and you won't get support for it yet. For example, the whole api app integrating
with logic apps thing - outright doesn't work. Social media login: doesn't work because of aforementioned CORS error. No hook, event or framework to control it either. The new app service is going to be fantastic, but hold fire on using
it until it's more developed.