Faulty mapping of UserClaims in IdentityResource, ApiResource and ApiScope

[tbureck]

When mapping from one of IdentityResource, ApiResource or ApiScope entities to their corresponding models, the UserClaims will not be mapped correctly. Instead of containing a list of claims, the property will contain a single list entry with the claim type being its value.

E.g. IdentityResource contains claims of type IdentityClaim. When mapping it, the resulting model will contain a single entry with value "IdentityServer4.MongoDB.Entities.IdentityClaim".

I didn't understand it to all detail, but I think this is because AutoMapper neglects the Select(x => x.Type) part of the expression determining what to map. Hence, it will try to map a UserClaim object to string by calling its ToString method. This results in its FQCN being mapped into the resulting collection.

There are two workarounds for this. Either implement a ToString method for the claim types or configure AutoMapper to map UserClaim objects to string by using its Type property. In a small POC I've chosen the latter because I think this is a pure mapping issue and should be resolved there.

This issue exists for documenting purposes, a PR is already in the making.