Get a client library
The client is available via Nuget.
The library has several packages with the prefix Digipost.Signature.Api.Client. If you are using the portal cases, use Digipost.Signature.Api.Client.Portal, and for direct cases, use Digipost.Signature.Api.Client.Direct.
If you want to download signed documents from the archive, use Digipost.Signature.Api.Client.Archive.
Source code is available on GitHub (digipost/signature-api-client-dotnet).
The client is available via Maven (no.digipost.signature:signature-api-client-java).
Javadoc is available at javadoc.io.
Source code is available on GitHub (digipost/signature-api-client-java).