Text Analytics Transparent Proxy Thoughts

layers.cs

// This is the convenience layer that customers interact with.
// This should look almost exactly like the current API:
//   https://apiview.dev/Assemblies/Review/2d2a87eaa70a43b8860f1c4e7135494b
//
// Because it isn't interacting with the swagger types, we probably need to clone the
// current implementation and use it as template.
//
public class TextAnalyticsClient
{
    TransportClient _transport = this.serviceVersion switch
    {
        v3.0 => new LegacyTransportClient(),
        v3.1 => new LegacyTransportclient(),
        2022-03-01 => new LanguageTransportClient()
    };

    public Task<DoAThing> SomeMethod(SomeType input)
    {
        await _transport.SomeMethod(SomeType input);
    }
}

// This is a neutral abstraction of the "second convenience" level.  It
// exists just to make the convenience layer's life easier.
//
// This is based on types from the convenience layer and looks very
// similar to the 5.2.0 API.
//
internal abstract class TransportClient
{
    public abstract Task<DoAThing> SomeMethod(SomeType input);
}

// This is the thing that knows how to take the convenience layer types
// and translate them into the Legacy swagger format.  This will look pretty
// similar to the legacy convenience layer.
//
internal class LegacyTransportClient
{
    public Task<DoAThing> SomeMethod(SomeType input)
    {
        OldType oldType = TranslateSomeType(input);
        OldThing oldResult = legacyRestClient.InvokeSomeMethod(oldType);

        return TranslateToDoAThing(oldResult);
    }
}

// This is the thing that knows how to take the convenience types
// and translate them into the Language swagger format.
//
// This looks like what a convenience layer would look like if we built one
// just for the new Language swagger.   But in our case, we're using it internally
// rather than exposing it.
//
internal class LanguageTransportClient
{
    public Task<DoAThing> SomeMethod(SomeType input)
    {
        NewType newType = TranslateSomeType(input);
        NewThing newResult = languageRestClient.InvokeSomeMethod(newType);

        return TranslateToDoAThing(newResult);
    }
}