Add summary comment.

src/DotNetCore.CAP.RabbitMQ/RabbitMQProducerClient.cs

-using System.Text;
+using System;
+using System.Text;
 using System.Threading.Tasks;
 using DotNetCore.CAP.Infrastructure;
 using Microsoft.Extensions.Logging;
@@ -36,5 +37,9 @@ namespace DotNetCore.CAP.RabbitMQ
                 return Task.CompletedTask;
             }
         }
+
+        public Task SendAsync<T>(string topic, T contentObj) {
+            throw new NotImplementedException();
+        }
     }
 }
\ No newline at end of file

src/DotNetCore.CAP/IBootstrapper.Default.cs

@@ -9,6 +9,9 @@ using Microsoft.Extensions.Options;
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// Default implement of <see cref="IBootstrapper"/>.
+    /// </summary>
     public class DefaultBootstrapper : IBootstrapper
     {
         private IApplicationLifetime _appLifetime;
@@ -27,6 +30,7 @@ namespace DotNetCore.CAP
             _appLifetime = appLifetime;
             Provider = provider;
             Servers = Provider.GetServices<IProcessingServer>();
+
             _cts = new CancellationTokenSource();
             _ctsRegistration = appLifetime.ApplicationStopping.Register(() =>
             {

src/DotNetCore.CAP/ICapProducerService.Default.cs

@@ -6,6 +6,9 @@ using Microsoft.Extensions.Logging;
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// Cap <see cref="ICapProducerService"/> default implement.
+    /// </summary>
     public class DefaultProducerService : ICapProducerService
     {
         private readonly ICapMessageStore _store;
@@ -29,13 +32,13 @@ namespace DotNetCore.CAP
             return StoreMessage(topic, content);
         }
 
-        public Task SendAsync<T>(string topic, T obj)
+        public Task SendAsync<T>(string topic, T contentObj)
         {
             if (topic == null) throw new ArgumentNullException(nameof(topic));
 
-            var content = Helper.ToJson(obj);
+            var content = Helper.ToJson(contentObj);
             if (content == null)
-                throw new InvalidCastException(nameof(obj));
+                throw new InvalidCastException(nameof(contentObj));
 
             return StoreMessage(topic, content);
         }

src/DotNetCore.CAP/ICapProducerService.cs

@@ -2,8 +2,25 @@
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// Cap producer service for store message to database.
+    /// </summary>
     public interface ICapProducerService
     {
+        /// <summary>
+        /// Send a message to cap job.
+        /// </summary>
+        /// <param name="topic">the topic name or exchange router key.</param>
+        /// <param name="content">message body content.</param>
         Task SendAsync(string topic, string content);
+
+        /// <summary>
+        /// Send a message to cap job.
+        /// </summary>
+        /// <typeparam name="T">The type of conetent object.</typeparam>
+        /// <param name="topic">the topic name or exchange router key.</param>
+        /// <param name="contentObj">object instance that will be serialized of json.</param>
+        /// <returns></returns>
+        Task SendAsync<T>(string topic, T contentObj);
     }
 }
\ No newline at end of file

src/DotNetCore.CAP/IConsumerClient.cs

@@ -5,6 +5,9 @@ using DotNetCore.CAP.Infrastructure;
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// consumer client 
+    /// </summary>
     public interface IConsumerClient : IDisposable
     {
         void Subscribe(string topic);

src/DotNetCore.CAP/IConsumerClientFactory.cs

@@ -5,8 +5,17 @@ using System.Threading.Tasks;
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// Consumer client factory to create consumer client instance.
+    /// </summary>
     public interface IConsumerClientFactory
     {
+        /// <summary>
+        /// Create a new instance of <see cref="IConsumerClient"/>.
+        /// </summary>
+        /// <param name="groupId"></param>
+        /// <param name="clientHostAddress"></param>
+        /// <returns></returns>
         IConsumerClient Create(string groupId, string clientHostAddress);
     }
 }

src/DotNetCore.CAP/IConsumerService.cs

 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// An empty interface, which is used to mark the current class have a CAP methods.
+    /// </summary>
     public interface IConsumerService
     {
     }

src/DotNetCore.CAP/IProcessingServer.cs

@@ -2,6 +2,9 @@
 
 namespace DotNetCore.CAP
 {
+    /// <summary>
+    /// A process thread abstract of job process.
+    /// </summary>
     public interface IProcessingServer : IDisposable
     {
         void Start();