fix lost connection and reconnect automatically

src/tarantool.client/Box.cs

@@ -1,11 +1,8 @@
-using System;
-using System.Linq;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 
 using ProGaudi.Tarantool.Client.Model;
 using ProGaudi.Tarantool.Client.Model.Requests;
 using ProGaudi.Tarantool.Client.Model.Responses;
-using ProGaudi.Tarantool.Client.Utils;
 
 namespace ProGaudi.Tarantool.Client
 {
@@ -15,40 +12,17 @@ public class Box : IBox
 
         private readonly ILogicalConnection _logicalConnection;
 
-        private readonly IResponseReader _responseReader;
-
-        private readonly INetworkStreamPhysicalConnection _physicalConnection;
-
         public Box(ClientOptions options)
         {
             _clientOptions = options;
             TarantoolConvertersRegistrator.Register(options.MsgPackContext);
 
-            _physicalConnection = new NetworkStreamPhysicalConnection();
-            _logicalConnection = new LogicalConnection(options, _physicalConnection);
-            _responseReader = new ResponseReader(_logicalConnection, options, _physicalConnection);
+            _logicalConnection = new LogicalConnectionWrapper(options);
         }
 
         public async Task Connect()
         {
-            await _physicalConnection.Connect(_clientOptions);
-
-            var greetingsResponseBytes = new byte[128];
-            var readCount = await _physicalConnection.ReadAsync(greetingsResponseBytes, 0, greetingsResponseBytes.Length);
-            if (readCount != greetingsResponseBytes.Length)
-            {
-                throw ExceptionHelper.UnexpectedGreetingBytesCount(readCount);
-            }
-
-            var greetings = new GreetingsResponse(greetingsResponseBytes);
-
-            _clientOptions.LogWriter?.WriteLine($"Greetings received, salt is {Convert.ToBase64String(greetings.Salt)} .");
-
-            _responseReader.BeginReading();
-
-            _clientOptions.LogWriter?.WriteLine("Server responses reading started.");
-
-            await LoginIfNotGuest(greetings);
+            await _logicalConnection.Connect();
         }
 
         public static async Task<Box> Connect(string replicationSource)
@@ -72,8 +46,7 @@ public void Dispose()
         {
             _clientOptions.LogWriter?.WriteLine("Box is disposing...");
             _clientOptions.LogWriter?.Flush();
-            _responseReader.Dispose();
-            _physicalConnection.Dispose();
+            _logicalConnection.Dispose();
         }
 
         public ISchema GetSchema()
@@ -141,21 +114,5 @@ public Task<DataResponse<TResponse[]>> Eval<TResponse>(string expression)
         {
             return Eval<TarantoolTuple, TResponse>(expression, TarantoolTuple.Empty);
         }
-
-        private async Task LoginIfNotGuest(GreetingsResponse greetings)
-        {
-            var singleNode = _clientOptions.ConnectionOptions.Nodes.Single();
-
-            if (string.IsNullOrEmpty(singleNode.Uri.UserName))
-            {
-                _clientOptions.LogWriter?.WriteLine("Guest mode, no authentication attempt.");
-                return;
-            }
-
-            var authenticateRequest = AuthenticationRequest.Create(greetings, singleNode.Uri);
-
-            await _logicalConnection.SendRequestWithEmptyResponse(authenticateRequest);
-            _clientOptions.LogWriter?.WriteLine($"Authentication request send: {authenticateRequest}");
-        }
     }
 }

src/tarantool.client/ILogicalConnection.cs

@@ -8,16 +8,18 @@
 
 namespace ProGaudi.Tarantool.Client
 {
-    public interface ILogicalConnection
+    using System;
+
+    public interface ILogicalConnection : IDisposable
     {
+        Task Connect();
+
+        bool IsConnected();
+
         Task SendRequestWithEmptyResponse<TRequest>(TRequest request)
             where TRequest : IRequest;
 
         Task<DataResponse<TResponse[]>> SendRequest<TRequest, TResponse>(TRequest request)
             where TRequest : IRequest;
-
-        TaskCompletionSource<MemoryStream> PopResponseCompletionSource(RequestId requestId, MemoryStream resultStream);
-
-        IEnumerable<TaskCompletionSource<MemoryStream>> PopAllResponseCompletionSources();
     }
 }

src/tarantool.client/INetworkStreamPhysicalConnection.cs

@@ -8,6 +8,7 @@ public interface INetworkStreamPhysicalConnection : IDisposable
     {
         Task Connect(ClientOptions options);
         Task Flush();
+        bool IsConnected();
         Task<int> ReadAsync(byte[] buffer, int offset, int count);
         void Write(byte[] buffer, int offset, int count);
     }

src/tarantool.client/IResponseReader.cs

@@ -2,8 +2,19 @@
 
 namespace ProGaudi.Tarantool.Client
 {
+    using System.IO;
+    using System.Threading.Tasks;
+
+    using ProGaudi.Tarantool.Client.Model;
+
     public interface IResponseReader : IDisposable
     {
         void BeginReading();
+
+        Task<MemoryStream> GetResponseTask(RequestId requestId);
+
+        void SetFaultedState();
+
+        bool IsFaultedState { get; }
     }
 }

src/tarantool.client/LogicalConnection.cs

@@ -20,20 +20,73 @@ internal class LogicalConnection : ILogicalConnection
     {
         private readonly MsgPackContext _msgPackContext;
 
-        private readonly INetworkStreamPhysicalConnection _physicalConnection;
+        private readonly ClientOptions _clientOptions;
 
-        private long _currentRequestId;
+        private readonly RequestIdCounter _requestIdCounter;
 
-        private readonly ConcurrentDictionary<RequestId, TaskCompletionSource<MemoryStream>> _pendingRequests =
-            new ConcurrentDictionary<RequestId, TaskCompletionSource<MemoryStream>>();
+        private INetworkStreamPhysicalConnection _physicalConnection;
+
+        private IResponseReader _responseReader;
 
         private readonly ILog _logWriter;
 
-        public LogicalConnection(ClientOptions options, INetworkStreamPhysicalConnection physicalConnection)
+        public LogicalConnection(ClientOptions options, RequestIdCounter requestIdCounter)
         {
+            _clientOptions = options;
+            _requestIdCounter = requestIdCounter;
             _msgPackContext = options.MsgPackContext;
             _logWriter = options.LogWriter;
-            _physicalConnection = physicalConnection;
+        }
+
+        public void Dispose()
+        {
+            Interlocked.Exchange(ref _responseReader, null)?.Dispose();
+            Interlocked.Exchange(ref _physicalConnection, null)?.Dispose();
+        }
+
+        public async Task Connect()
+        {
+            _physicalConnection = new NetworkStreamPhysicalConnection();
+            await _physicalConnection.Connect(_clientOptions);
+
+            var greetingsResponseBytes = new byte[128];
+            var readCount = await _physicalConnection.ReadAsync(greetingsResponseBytes, 0, greetingsResponseBytes.Length);
+            if (readCount != greetingsResponseBytes.Length)
+            {
+                throw ExceptionHelper.UnexpectedGreetingBytesCount(readCount);
+            }
+
+            var greetings = new GreetingsResponse(greetingsResponseBytes);
+
+            _clientOptions.LogWriter?.WriteLine($"Greetings received, salt is {Convert.ToBase64String(greetings.Salt)} .");
+
+            _responseReader = new ResponseReader(_clientOptions, _physicalConnection);
+            _responseReader.BeginReading();
+
+            _clientOptions.LogWriter?.WriteLine("Server responses reading started.");
+
+            await LoginIfNotGuest(greetings);
+        }
+
+        public bool IsConnected()
+        {
+            return !(_responseReader?.IsFaultedState ?? true) && (_physicalConnection?.IsConnected() ?? false);
+        }
+
+        private async Task LoginIfNotGuest(GreetingsResponse greetings)
+        {
+            var singleNode = _clientOptions.ConnectionOptions.Nodes.Single();
+
+            if (string.IsNullOrEmpty(singleNode.Uri.UserName))
+            {
+                _clientOptions.LogWriter?.WriteLine("Guest mode, no authentication attempt.");
+                return;
+            }
+
+            var authenticateRequest = AuthenticationRequest.Create(greetings, singleNode.Uri);
+
+            await SendRequestWithEmptyResponse(authenticateRequest);
+            _clientOptions.LogWriter?.WriteLine($"Authentication request send: {authenticateRequest}");
         }
 
         public async Task SendRequestWithEmptyResponse<TRequest>(TRequest request)
@@ -48,15 +101,6 @@ public async Task<DataResponse<TResponse[]>> SendRequest<TRequest, TResponse>(TR
             return await SendRequestImpl<TRequest, DataResponse<TResponse[]>>(request);
         }
 
-        public TaskCompletionSource<MemoryStream> PopResponseCompletionSource(RequestId requestId, MemoryStream resultStream)
-        {
-            TaskCompletionSource<MemoryStream> request;
-
-            return _pendingRequests.TryRemove(requestId, out request)
-                ? request
-                : null;
-        }
-
         public static byte[] ReadFully(Stream input)
         {
             input.Position = 0;
@@ -72,31 +116,33 @@ public static byte[] ReadFully(Stream input)
             }
         }
 
-        public IEnumerable<TaskCompletionSource<MemoryStream>> PopAllResponseCompletionSources()
-        {
-            var result = _pendingRequests.Values.ToArray();
-            _pendingRequests.Clear();
-            return result;
-        }
-
         private async Task<TResponse> SendRequestImpl<TRequest, TResponse>(TRequest request)
             where TRequest : IRequest
         {
             var bodyBuffer = MsgPackSerializer.Serialize(request, _msgPackContext);
 
-            var requestId = GetRequestId();
-            var responseTask = GetResponseTask(requestId);
+            var requestId = _requestIdCounter.GetRequestId();
+            var responseTask = _responseReader.GetResponseTask(requestId);
 
             long headerLength;
             var headerBuffer = CreateAndSerializeBuffer(request, requestId, bodyBuffer, out headerLength);
 
-            lock (_physicalConnection)
+            try
             {
-                _logWriter?.WriteLine($"Begin sending request header buffer, requestId: {requestId}, code: {request.Code}, length: {headerBuffer.Length}");
-                _physicalConnection.Write(headerBuffer, 0, Constants.PacketSizeBufferSize + (int) headerLength);
+                lock (_physicalConnection)
+                {
+                    _logWriter?.WriteLine($"Begin sending request header buffer, requestId: {requestId}, code: {request.Code}, length: {headerBuffer.Length}");
+                    _physicalConnection.Write(headerBuffer, 0, Constants.PacketSizeBufferSize + (int)headerLength);
 
-                _logWriter?.WriteLine($"Begin sending request body buffer, length: {bodyBuffer.Length}");
-                _physicalConnection.Write(bodyBuffer, 0, bodyBuffer.Length);
+                    _logWriter?.WriteLine($"Begin sending request body buffer, length: {bodyBuffer.Length}");
+                    _physicalConnection.Write(bodyBuffer, 0, bodyBuffer.Length);
+                }
+            }
+            catch (Exception ex)
+            {
+                _responseReader.SetFaultedState();
+                _logWriter?.WriteLine($"Request with requestId {requestId} failed, header:\n{ToReadableString(headerBuffer)} \n body: \n{ToReadableString(bodyBuffer)}");
+                throw;
             }
 
             try
@@ -137,22 +183,5 @@ private byte[] CreateAndSerializeBuffer<TRequest>(
             MsgPackSerializer.Serialize(packetLength, stream, _msgPackContext);
             return packetSizeBuffer;
         }
-
-        private RequestId GetRequestId()
-        {
-            var requestId = Interlocked.Increment(ref _currentRequestId);
-            return (RequestId) (ulong) requestId;
-        }
-
-        private Task<MemoryStream> GetResponseTask(RequestId requestId)
-        {
-            var tcs = new TaskCompletionSource<MemoryStream>();
-            if (!_pendingRequests.TryAdd(requestId, tcs))
-            {
-                throw ExceptionHelper.RequestWithSuchIdAlreadySent(requestId);
-            }
-
-            return tcs.Task;
-        }
     }
 }