Adjustments to interfaces to improve the mockability and faking of NATS for unit testing in consumer apps.

src/NATS.Client/AsyncSub.cs

@@ -84,8 +84,7 @@ internal override bool processMsg(Msg msg)
                 {
                     if (localHandler != null)
                     {
-                        var msgHandlerEventArgs = new MsgHandlerEventArgs();
-                        msgHandlerEventArgs.msg = msg;
+                        var msgHandlerEventArgs = new MsgHandlerEventArgs(msg);
 
                         localHandler(this, msgHandlerEventArgs);
                     }

src/NATS.Client/ConnectionFactory.cs

@@ -18,7 +18,7 @@ namespace NATS.Client
     /// <summary>
     /// Provides factory methods to create connections to NATS Servers.
     /// </summary>
-    public sealed class ConnectionFactory
+    public sealed class ConnectionFactory : IConnectionFactory
     {
         /// <summary>
         /// Initializes a new instance of the <see cref="ConnectionFactory"/> class,

src/NATS.Client/EncodedConn.cs

@@ -234,7 +234,7 @@ public void msgHandlerToEncoderHandler(Object sender, MsgHandlerEventArgs args)
                 EncodedMessageEventArgs ehev = new EncodedMessageEventArgs();
                 try
                 {
-                    byte[] data = args.msg != null ? args.msg.Data : null;
+                    byte[] data = args.Message != null ? args.Message.Data : null;
                     ehev.obj = c.onDeserialize(data);
                 }
                 catch (Exception ex)
@@ -243,9 +243,9 @@ public void msgHandlerToEncoderHandler(Object sender, MsgHandlerEventArgs args)
                     return;
                 }
 
-                ehev.subject = args.msg.Subject;
-                ehev.reply = args.msg.Reply;
-                ehev.msg = args.msg;
+                ehev.subject = args.Message.Subject;
+                ehev.reply = args.Message.Reply;
+                ehev.msg = args.Message;
 
                 try
                 {

src/NATS.Client/IConnectionFactory.cs

@@ -0,0 +1,156 @@
+// Copyright 2015-2022 The NATS Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+
+namespace NATS.Client
+{
+    public interface IConnectionFactory
+    {
+        /// <summary>
+        /// Attempt to connect to the NATS server referenced by <paramref name="url"/>.
+        /// </summary>
+        /// <remarks>
+        /// <para><paramref name="url"/> can contain username/password semantics.
+        /// Comma seperated arrays are also supported, e.g. <c>&quot;urlA, urlB&quot;</c>.</para>
+        /// </remarks>
+        /// <param name="url">A string containing the URL (or URLs) to the NATS Server. See the Remarks
+        /// section for more information.</param>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IConnection CreateConnection(string url);
+
+        /// <summary>
+        /// Attempt to connect to the NATS server referenced by <paramref name="url"/> with NATS 2.0 credentials.
+        /// </summary>
+        /// <remarks>
+        /// <para><paramref name="url"/>
+        /// Comma seperated arrays are also supported, e.g. <c>&quot;urlA, urlB&quot;</c>.</para>
+        /// </remarks>
+        /// <param name="url">A string containing the URL (or URLs) to the NATS Server. See the Remarks
+        /// section for more information.</param>
+        /// <param name="credentialsPath">The full path to a chained credentials file.</param>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IConnection CreateConnection(string url, string credentialsPath);
+
+        /// <summary>
+        /// Attempt to connect to the NATS server referenced by <paramref name="url"/> with NATS 2.0 credentials.
+        /// </summary>
+        /// <remarks>
+        /// <para><paramref name="url"/>
+        /// Comma seperated arrays are also supported, e.g. <c>&quot;urlA, urlB&quot;</c>.</para>
+        /// </remarks>
+        /// <param name="url">A string containing the URL (or URLs) to the NATS Server. See the Remarks
+        /// section for more information.</param>
+        /// <param name="jwt">The path to a user's public JWT credentials.</param>
+        /// <param name="privateNkey">The path to a file for user user's private Nkey seed.</param>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IConnection CreateConnection(string url, string jwt, string privateNkey);
+
+        /// <summary>
+        /// Create a connection to the NATs server using the default options.
+        /// </summary>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        /// <seealso cref="ConnectionFactory.GetDefaultOptions"/>
+        IConnection CreateConnection();
+
+        /// <summary>
+        /// Create a connection to a NATS Server defined by the given options.
+        /// </summary>
+        /// <param name="opts">The NATS client options to use for this connection.</param>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IConnection CreateConnection(Options opts);
+
+        /// <summary>
+        /// Attempt to connect to the NATS server using TLS referenced by <paramref name="url"/>.
+        /// </summary>
+        /// <remarks>
+        /// <para><paramref name="url"/> can contain username/password semantics.
+        /// Comma seperated arrays are also supported, e.g. urlA, urlB.</para>
+        /// </remarks>
+        /// <param name="url">A string containing the URL (or URLs) to the NATS Server. See the Remarks
+        /// section for more information.</param>
+        /// <returns>An <see cref="IConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IConnection CreateSecureConnection(string url);
+
+        /// <summary>
+        /// Attempt to connect to the NATS server, with an encoded connection, using the default options.
+        /// </summary>
+        /// <returns>An <see cref="IEncodedConnection"/> object connected to the NATS server.</returns>
+        /// <seealso cref="ConnectionFactory.GetDefaultOptions"/>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IEncodedConnection CreateEncodedConnection();
+
+        /// <summary>
+        /// Attempt to connect to the NATS server, with an encoded connection, referenced by <paramref name="url"/>.
+        /// </summary>
+        /// <remarks>
+        /// <para><paramref name="url"/> can contain username/password semantics.
+        /// Comma seperated arrays are also supported, e.g. urlA, urlB.</para>
+        /// </remarks>
+        /// <param name="url">A string containing the URL (or URLs) to the NATS Server. See the Remarks
+        /// section for more information.</param>
+        /// <returns>An <see cref="IEncodedConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IEncodedConnection CreateEncodedConnection(string url);
+
+        /// <summary>
+        /// Attempt to connect to the NATS server, with an encoded connection, using the given options.
+        /// </summary>
+        /// <param name="opts">The NATS client options to use for this connection.</param>
+        /// <returns>An <see cref="IEncodedConnection"/> object connected to the NATS server.</returns>
+        /// <exception cref="NATSNoServersException">No connection to a NATS Server could be established.</exception>
+        /// <exception cref="NATSConnectionException"><para>A timeout occurred connecting to a NATS Server.</para>
+        /// <para>-or-</para>
+        /// <para>An exception was encountered while connecting to a NATS Server. See <see cref="Exception.InnerException"/> for more
+        /// details.</para></exception>
+        IEncodedConnection CreateEncodedConnection(Options opts);
+    }
+}

src/NATS.Client/KeyValue/KeyValueWatchSubscription.cs

@@ -69,7 +69,7 @@ public KeyValueWatchSubscription(KeyValue kv, string keyPattern,
 
             EventHandler<MsgHandlerEventArgs> handler = (sender, args) =>
             {
-                KeyValueEntry kve = new KeyValueEntry(args.msg);
+                KeyValueEntry kve = new KeyValueEntry(args.Message);
                 if (includeDeletes || kve.Operation.Equals(KeyValueOperation.Put))
                 {
                     watcher.Watch(kve);

src/NATS.Client/NATS.cs

@@ -496,15 +496,16 @@ internal class IC
     /// </summary>
     public class MsgHandlerEventArgs : EventArgs
     {
-        internal Msg msg = null;
+        public MsgHandlerEventArgs(Msg message)
+        {
+            Message = message;
+        }
+
 
         /// <summary>
         /// Retrieves the message.
         /// </summary>
-        public Msg Message
-        {
-            get { return msg; }
-        }
+        public Msg Message { get; }
     }
 
     // Borrowed from:  https://stackoverflow.com/a/7135008

src/Tests/IntegrationTestsInternal/TestOrderedConsumer.cs

@@ -144,8 +144,8 @@ void DummyTestHandler(object sender, MsgHandlerEventArgs args) { }
                 void TestHandler(object sender, MsgHandlerEventArgs args)
                 {
                     int i = received.Increment() - 1;
-                    ssFlags[i] = new InterlockedLong((long)args.msg.MetaData.StreamSequence);
-                    csFlags[i] = new InterlockedLong((long)args.msg.MetaData.ConsumerSequence);
+                    ssFlags[i] = new InterlockedLong((long)args.Message.MetaData.StreamSequence);
+                    csFlags[i] = new InterlockedLong((long)args.Message.MetaData.ConsumerSequence);
                     latch.Signal();
                 }