fixed not return connection to pool bug.

src/DotNetCore.CAP.RabbitMQ/ConnectionPool.cs

@@ -8,7 +8,7 @@ namespace DotNetCore.CAP.RabbitMQ
 {
     public class ConnectionPool : IConnectionPool, IDisposable
     {
-        private const int DefaultPoolSize = 32;
+        private const int DefaultPoolSize = 15;
 
         private readonly ConcurrentQueue<IConnection> _pool = new ConcurrentQueue<IConnection>();
 

src/DotNetCore.CAP.RabbitMQ/PublishQueueExecutor.cs

@@ -28,9 +28,10 @@ namespace DotNetCore.CAP.RabbitMQ
 
         public override Task<OperateResult> PublishAsync(string keyName, string content)
         {
+            var connection = _connectionPool.Rent();
+
             try
             {
-                var connection = _connectionPool.Rent();
                 using (var channel = connection.CreateModel())
                 {
                     var body = Encoding.UTF8.GetBytes(content);
@@ -56,6 +57,10 @@ namespace DotNetCore.CAP.RabbitMQ
                         Description = ex.Message
                     }));
             }
+            finally
+            {
+                _connectionPool.Return(connection);
+            }
         }
     }
 }
\ No newline at end of file

src/DotNetCore.CAP.RabbitMQ/RabbitMQConsumerClient.cs

@@ -14,7 +14,7 @@ namespace DotNetCore.CAP.RabbitMQ
         private readonly string _queueName;
         private readonly RabbitMQOptions _rabbitMQOptions;
 
-        private IConnection _connection;
+        private ConnectionPool _connectionPool;
         private IModel _channel;
         private ulong _deliveryTag;
 
@@ -23,11 +23,11 @@ namespace DotNetCore.CAP.RabbitMQ
         public event EventHandler<string> OnError;
 
         public RabbitMQConsumerClient(string queueName,
-             IConnection connection,
+             ConnectionPool connectionPool,
              RabbitMQOptions options)
         {
             _queueName = queueName;
-            _connection = connection;
+            _connectionPool = connectionPool;
             _rabbitMQOptions = options;
             _exchageName = options.TopicExchangeName;
 
@@ -36,7 +36,9 @@ namespace DotNetCore.CAP.RabbitMQ
 
         private void InitClient()
         {
-            _channel = _connection.CreateModel();
+            var connection = _connectionPool.Rent();
+
+            _channel = connection.CreateModel();
 
             _channel.ExchangeDeclare(
                 exchange: _exchageName,
@@ -49,6 +51,8 @@ namespace DotNetCore.CAP.RabbitMQ
                 exclusive: false,
                 autoDelete: false,
                 arguments: arguments);
+
+            _connectionPool.Return(connection);
         }
 
         public void Subscribe(IEnumerable<string> topics)
@@ -81,7 +85,6 @@ namespace DotNetCore.CAP.RabbitMQ
         public void Dispose()
         {
             _channel.Dispose();
-            _connection.Dispose();
         }
 
         private void OnConsumerReceived(object sender, BasicDeliverEventArgs e)

src/DotNetCore.CAP.RabbitMQ/RabbitMQConsumerClientFactory.cs

@@ -6,18 +6,18 @@ namespace DotNetCore.CAP.RabbitMQ
     internal sealed class RabbitMQConsumerClientFactory : IConsumerClientFactory
     {
         private readonly RabbitMQOptions _rabbitMQOptions;
-        private readonly IConnection _connection;
+        private readonly ConnectionPool _connectionPool;
 
 
         public RabbitMQConsumerClientFactory(RabbitMQOptions rabbitMQOptions, ConnectionPool pool)
         {
             _rabbitMQOptions = rabbitMQOptions;
-            _connection = pool.Rent();
+            _connectionPool = pool;
         }
 
         public IConsumerClient Create(string groupId)
         {
-            return new RabbitMQConsumerClient(groupId, _connection, _rabbitMQOptions);
+            return new RabbitMQConsumerClient(groupId, _connectionPool, _rabbitMQOptions);
         }
     }
 }
\ No newline at end of file