feat: an error happened in the transaction, allow one empty rollback (#190)

Author: KirillKurdyukov

CHANGELOG.md

@@ -1,3 +1,5 @@
+- If an error happened in the transaction, allow one empty rollback
+
 ## v0.7.0
 - Parsed @param then prepared for use with $ prefix (@p -> $p)
 - Fully integrated with Dapper

src/Ydb.Sdk/src/Ado/YdbCommand.cs

@@ -122,7 +122,7 @@ protected override DbTransaction? DbTransaction
         {
             if (value is null or YdbTransaction)
             {
-                _ydbTransaction = (YdbTransaction?)value;
+                Transaction = (YdbTransaction?)value;
             }
             else
             {
@@ -132,21 +132,7 @@ protected override DbTransaction? DbTransaction
         }
     }
 
-    public new YdbTransaction? Transaction
-    {
-        get
-        {
-            if (_ydbTransaction?.Completed ?? false)
-            {
-                _ydbTransaction = null;
-            }
-
-            return _ydbTransaction;
-        }
-        set => _ydbTransaction = value;
-    }
-
-    private YdbTransaction? _ydbTransaction;
+    public new YdbTransaction? Transaction { get; set; }
 
     public override bool DesignTimeVisible { get; set; }
 

src/Ydb.Sdk/src/Ado/YdbDataReader.cs

@@ -519,7 +519,7 @@ private void OnFailReadStream()
         ReaderState = State.Closed;
         if (_ydbTransaction != null)
         {
-            _ydbTransaction.Completed = true;
+            _ydbTransaction.Failed = true;
         }
     }
 

src/Ydb.Sdk/src/Ado/YdbTransaction.cs

@@ -9,12 +9,26 @@ public sealed class YdbTransaction : DbTransaction
 {
     private readonly TxMode _txMode;
 
+    private bool _failed;
+
     internal string? TxId { get; set; }
-    internal bool Completed { get; set; }
+    internal bool Completed { get; private set; }
+
+    internal bool Failed
+    {
+        private get => _failed;
+        set
+        {
+            _failed = value;
+            Completed = true;
+        }
+    }
 
-    internal TransactionControl TransactionControl => TxId == null
-        ? new TransactionControl { BeginTx = _txMode.TransactionSettings() }
-        : new TransactionControl { TxId = TxId };
+    internal TransactionControl? TransactionControl => Completed
+        ? null
+        : TxId == null
+            ? new TransactionControl { BeginTx = _txMode.TransactionSettings() }
+            : new TransactionControl { TxId = TxId };
 
     internal YdbTransaction(YdbConnection ydbConnection, TxMode txMode)
     {
@@ -41,6 +55,13 @@ public override void Rollback()
     // TODO propagate cancellation token
     public override async Task RollbackAsync(CancellationToken cancellationToken = new())
     {
+        if (Failed)
+        {
+            Failed = false;
+
+            return;
+        }
+
         await FinishTransaction(txId => DbConnection.Session.RollbackTransaction(txId));
     }
 

src/Ydb.Sdk/tests/Ado/YdbExceptionTests.cs

@@ -21,7 +21,7 @@ public async Task IsTransient_WhenSchemaError_ReturnFalse()
     }
 
     [Fact]
-    public async Task IsTransient_WhenAborted_ReturnTrue()
+    public async Task IsTransient_WhenAborted_ReturnTrueAndMakeEmptyRollback()
     {
         var bankTable = $"Bank_{Utils.Net}";
         await using var ydbConnection = new YdbConnection();
@@ -57,5 +57,13 @@ public async Task IsTransient_WhenAborted_ReturnTrue()
         {
             CommandText = $"DROP TABLE {bankTable}"
         }.ExecuteNonQueryAsync();
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction.Commit()).Message);
+
+        await ydbCommand.Transaction!.RollbackAsync();
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction!.Commit()).Message);
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction!.Rollback()).Message);
     }
 }

src/Ydb.Sdk/tests/Ado/YdbTransactionTests.cs

@@ -97,7 +97,7 @@ public void Commit_WhenEmptyYdbCommand_DoNothing()
     }
 
     [Fact]
-    public void Commit_WhenDoubleCommit_ThrowException()
+    public void CommitAndRollback_WhenDoubleCommit_ThrowException()
     {
         using var connection = new YdbConnection();
         connection.Open();
@@ -165,7 +165,7 @@ public void CommitAndRollback_WhenConnectionIsClosed_ThrowException()
     }
 
     [Fact]
-    public void Commit_WhenConnectionIsClosedAndTxDoesNotStarted_ThrowException()
+    public void CommitAndRollback_WhenConnectionIsClosedAndTxDoesNotStarted_ThrowException()
     {
         using var connection = new YdbConnection();
         connection.Open();
@@ -179,6 +179,27 @@ public void Commit_WhenConnectionIsClosedAndTxDoesNotStarted_ThrowException()
             Assert.Throws<InvalidOperationException>(() => ydbTransaction.Rollback()).Message);
     }
 
+    [Fact]
+    public void CommitAndRollback_WhenTransactionIsFailed_ThrowException()
+    {
+        using var connection = new YdbConnection();
+        connection.Open();
+
+        var ydbCommand = connection.CreateCommand();
+        ydbCommand.Transaction = connection.BeginTransaction();
+        ydbCommand.Transaction.Failed = true;
+        ydbCommand.Transaction.TxId = "no_tx";
+
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction.Commit()).Message);
+
+        ydbCommand.Transaction.Rollback(); // Make completed
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction.Commit()).Message);
+        Assert.Equal("This YdbTransaction has completed; it is no longer usable",
+            Assert.Throws<InvalidOperationException>(() => ydbCommand.Transaction.Rollback()).Message);
+    }
+
     public async Task InitializeAsync()
     {
         await using var connection = new YdbConnection();