Add possibility to start transaction from session

src/Session.Tests/MongoSessionProviderTests.cs

@@ -65,6 +65,26 @@ public async Task StartSessionAsync_ShouldStartSession()
  clientSessionHandle.IsInTransaction.Should().BeFalse();
  }
 
+ [Fact]
+ public async Task StartTransaction_ShouldBeginTransaction()
+ {
+ // Arrange
+ ISessionProvider<ITestScope> sessionProvider = _serviceProvider
+ .GetRequiredService<ISessionProvider<ITestScope>>();
+ ISession session = await sessionProvider
+ .StartSessionAsync(CancellationToken.None);
+
+ // Act
+ ITransactionSession transactionSession = session
+ .StartTransaction(CancellationToken.None);
+
+ // Assert
+ transactionSession.Should().NotBeNull();
+ IClientSessionHandle clientSessionHandle = transactionSession.GetSessionHandle();
+ clientSessionHandle.ServerSession.Id["id"].AsGuid.Should().NotBeEmpty();
+ clientSessionHandle.IsInTransaction.Should().BeTrue();
+ }
+
  [Fact]
  public async Task MongoSession_Dispose_ShouldDisposeSession()
  {

src/Session/ISession.cs

@@ -9,4 +9,7 @@ public interface ISession : IDisposable
  Task<T> WithTransactionAsync<T>(
  Func<ISession, CancellationToken, Task<T>> action,
  CancellationToken cancellationToken);
+
+ ITransactionSession StartTransaction(
+ CancellationToken cancellationToken);
 }

src/Session/Internal/MongoSession.cs

@@ -7,16 +7,14 @@ namespace MongoDB.Extensions.Session;
 
 internal sealed class MongoSession : ISession
 {
+ private readonly TransactionOptions _transactionOptions;
  private bool _disposed;
 
- private static TransactionOptions TransactionOptions { get; } = new(
- ReadConcern.Majority,
- ReadPreference.Primary,
- WriteConcern.WMajority.With(journal: true),
- TimeSpan.FromSeconds(180));
-
- public MongoSession(IClientSessionHandle clientSession)
+ public MongoSession(
+ IClientSessionHandle clientSession,
+ TransactionOptions transactionOptions)
  {
+ _transactionOptions = transactionOptions;
  Session = clientSession;
  }
 
@@ -27,9 +25,15 @@ public MongoSession(IClientSessionHandle clientSession)
  CancellationToken cancellationToken)
  {
  return Session.WithTransactionAsync<T>(
- (_, ct) => action(this, ct),
- TransactionOptions,
- cancellationToken);
+ (_, ct) => action(this, ct), _transactionOptions, cancellationToken);
+ }
+
+ public ITransactionSession StartTransaction(
+ CancellationToken cancellationToken)
+ {
+ Session.StartTransaction(_transactionOptions);
+
+ return new MongoTransactionSession(Session, cancellationToken);
  }
 
  private void Dispose(bool disposing)

src/Session/Internal/MongoSessionProvider.cs

@@ -16,26 +16,19 @@ public MongoSessionProvider(TContext context)
  _mongoClient = context.Client;
  }
 
- public Task<ITransactionSession> BeginTransactionAsync(
- CancellationToken cancellationToken)
- {
- return BeginTransactionAsync(true, cancellationToken);
- }
+ protected virtual TransactionOptions TransactionOptions { get; } = new(
+ ReadConcern.Majority,
+  ReadPreference.Primary,
+ WriteConcern.WMajority.With(journal: true),
+  TimeSpan.FromSeconds(180));
 
- private async Task<ITransactionSession> BeginTransactionAsync(
- bool safeModeEnabled,
+ public async Task<ITransactionSession> BeginTransactionAsync(
  CancellationToken cancellationToken)
  {
  IClientSessionHandle clientSession = await _mongoClient
  .StartSessionAsync(cancellationToken: cancellationToken);
 
- var transactionOptions = new TransactionOptions(
- ReadConcern.Majority,
- ReadPreference.Primary,
- WriteConcern.WMajority.With(journal: safeModeEnabled),
- TimeSpan.FromSeconds(180));
-
- clientSession.StartTransaction(transactionOptions);
+ clientSession.StartTransaction(TransactionOptions);
 
  return new MongoTransactionSession(clientSession, cancellationToken);
  }
@@ -46,6 +39,6 @@ public MongoSessionProvider(TContext context)
  IClientSessionHandle clientSession = await _mongoClient
  .StartSessionAsync(cancellationToken: cancellationToken);
 
- return new MongoSession(clientSession);
+ return new MongoSession(clientSession, TransactionOptions);
  }
 }

src/Session/Internal/MongoTransactionSession.cs

@@ -5,7 +5,7 @@
 
 namespace MongoDB.Extensions.Session;
 
-internal class MongoTransactionSession : ITransactionSession
+internal sealed class MongoTransactionSession : ITransactionSession
 {
  private readonly CancellationToken _cancellationToken;
  private bool _disposed;
@@ -25,7 +25,7 @@ public async Task CommitAsync()
  await Session.CommitTransactionAsync(_cancellationToken);
  }
 
- protected virtual void Dispose(bool disposing)
+ private void Dispose(bool disposing)
  {
  if (!_disposed)
  {