Adding support for authentication per binding

Author: darkl

src/netstandard/WampSharp/WAMP2/V2/Authentication/Host/WampMultiAuthenticationHost.cs

@@ -0,0 +1,113 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using WampSharp.V2.Authentication;
+using WampSharp.V2.Binding;
+using WampSharp.V2.Binding.Transports;
+using WampSharp.V2.Core;
+using WampSharp.V2.Realm;
+
+// ReSharper disable once CheckNamespace
+namespace WampSharp.V2
+{
+    /// <summary>
+    /// An implementation of <see cref="IWampHost"/> that supports authentication.
+    /// </summary>
+    public class WampMultiAuthenticationHost : WampHost, IWampMultiAuthenticationHost
+    {
+        private readonly IWampSessionAuthenticatorFactory mDefaultAuthenticatorFactory;
+
+        /// <summary>
+        /// Initializes a new instance of <see cref="WampMultiAuthenticationHost"/> given the
+        /// <see cref="IWampSessionAuthenticatorFactory"/> to use.
+        /// </summary>
+        /// <param name="defaultAuthenticatorFactory">A default <see cref="IWampSessionAuthenticatorFactory"/> that will be used for the overload <see cref="RegisterTransport(IWampTransport,IEnumerable{WampSharp.V2.Binding.IWampBinding})"/></param>
+        /// <param name="realmContainer">The <see cref="IWampRealmContainer"/> associated with this
+        /// host.</param>
+        /// <param name="uriValidator">The <see cref="IWampUriValidator"/> used to validate uris.</param>
+        public WampMultiAuthenticationHost(IWampSessionAuthenticatorFactory defaultAuthenticatorFactory = null,
+                                           IWampRealmContainer realmContainer = null,
+                                           IWampUriValidator uriValidator = null)
+            : base(realmContainer, uriValidator)
+        {
+            mDefaultAuthenticatorFactory = defaultAuthenticatorFactory;
+        }
+
+        public void RegisterTransport(IWampTransport transport, IDictionary<IWampBinding, IWampSessionAuthenticatorFactory> bindingToAuthenticatorFactory)
+        {
+            IEnumerable<IWampBinding> authenticationBindings =
+                bindingToAuthenticatorFactory
+                    .Select(binding =>
+                                CreateAuthenticationBinding((dynamic) binding.Key,
+                                                            binding.Value))
+                    .Cast<IWampBinding>()
+                    .Where(x => x != null);
+
+            base.RegisterTransport(transport, authenticationBindings);
+        }
+
+        public override void RegisterTransport(IWampTransport transport, IEnumerable<IWampBinding> bindings)
+        {
+            if (mDefaultAuthenticatorFactory == null)
+            {
+                ThrowHelper.NoDefaultSessionAuthenticatorWasProvided();
+            }
+
+            IDictionary<IWampBinding, IWampSessionAuthenticatorFactory> bindingToDefaultAuthenticator = 
+                bindings.ToDictionary(x => x, x => mDefaultAuthenticatorFactory);
+
+            RegisterTransport(transport, bindingToDefaultAuthenticator);
+        }
+
+        private IWampBinding CreateAuthenticationBinding<TMessage>
+            (IWampTextBinding<TMessage> binding, IWampSessionAuthenticatorFactory authenticatorFactory)
+        {
+            ThrowHelper.ValidateSessionAuthenticatorFactoryWasProvided(authenticatorFactory, binding);
+            return new WampAuthenticationTextBinding<TMessage>(binding, authenticatorFactory, this.UriValidator);
+        }
+
+        private IWampBinding CreateAuthenticationBinding<TMessage>
+            (IWampBinaryBinding<TMessage> binding, IWampSessionAuthenticatorFactory authenticatorFactory)
+        {
+            ThrowHelper.ValidateSessionAuthenticatorFactoryWasProvided(authenticatorFactory, binding);
+            return new WampAuthenticationBinaryBinding<TMessage>(binding, authenticatorFactory, this.UriValidator);
+        }
+
+        private IWampBinding CreateAuthenticationBinding<TMessage>
+            (IWampBinding<TMessage> binding, IWampSessionAuthenticatorFactory authenticatorFactory)
+        {
+            ThrowHelper.ValidateSessionAuthenticatorFactoryWasProvided(authenticatorFactory, binding);
+            return new WampAuthenticationBinding<TMessage>(binding, authenticatorFactory, this.UriValidator);
+        }
+
+        /// <summary>
+        /// Fallback in case that binding doesn't implement
+        /// IWampBinding{TMessage}
+        /// </summary>
+        /// <param name="binding"></param>
+        /// <param name="authenticatorFactory"></param>
+        /// <returns></returns>
+        private IWampBinding CreateAuthenticationBinding(IWampBinding binding, IWampSessionAuthenticatorFactory authenticatorFactory)
+        {
+            return null;
+        }
+
+        private static class ThrowHelper
+        {
+            public static void ValidateSessionAuthenticatorFactoryWasProvided(IWampSessionAuthenticatorFactory authenticatorFactory, IWampBinding binding)
+            {
+                if (authenticatorFactory == null)
+                {
+                    throw new
+                        ArgumentException($"No IWampSessionAuthenticatorFactory was provided for the binding named '{binding.Name}'.");
+                }
+            }
+
+            public static void NoDefaultSessionAuthenticatorWasProvided()
+            {
+                throw new
+                    ArgumentException("No default IWampSessionAuthenticatorFactory was provided. Either provide a default IWampSessionAuthenticatorFactory in the constructor, or call RegisterTransport with the desired IWampSessionAuthenticatorFactory");
+            }
+        }
+    }
+}

src/netstandard/WampSharp/WAMP2/V2/Authentication/IWampMultiAuthenticationHost.cs

@@ -0,0 +1,12 @@
+using System.Collections.Generic;
+using WampSharp.V2.Binding;
+using WampSharp.V2.Binding.Transports;
+
+namespace WampSharp.V2.Authentication
+{
+    public interface IWampMultiAuthenticationHost : IWampHost
+    {
+        void RegisterTransport(IWampTransport transport,
+                               IDictionary<IWampBinding, IWampSessionAuthenticatorFactory> bindingToAuthenticatorFactory);
+    }
+}