refactor(Spanner): Simplify access to a transaction's timestamp bound information

Author: amanda-tarafa

apis/Google.Cloud.Spanner.Data/Google.Cloud.Spanner.Data.Tests/SpannerTransactionCreationOptionsTests.cs

@@ -56,6 +56,7 @@ public void ReadWrite_Values()
 
         Assert.Null(readWrite.TimestampBound);
         Assert.Null(readWrite.TransactionId);
+        Assert.Null(readWrite.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadWrite, readWrite.TransactionMode);
         Assert.False(readWrite.IsDetached);
         Assert.False(readWrite.IsSingleUse);
@@ -73,6 +74,7 @@ public void PartitionedDml_Values()
 
         Assert.Null(partitionedDml.TimestampBound);
         Assert.Null(partitionedDml.TransactionId);
+        Assert.Null(partitionedDml.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadWrite, partitionedDml.TransactionMode);
         Assert.False(partitionedDml.IsDetached);
         Assert.False(partitionedDml.IsSingleUse);
@@ -90,6 +92,7 @@ public void ReadOnly_Values()
 
         Assert.Equal(TimestampBound.Strong, readOnly.TimestampBound);
         Assert.Null(readOnly.TransactionId);
+        Assert.Equal(TimestampBound.Strong, readOnly.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadOnly, readOnly.TransactionMode);
         Assert.False(readOnly.IsDetached);
         Assert.False(readOnly.IsSingleUse);
@@ -106,6 +109,7 @@ public void ForTimestampBoundReadOnly_Null()
         var options = SpannerTransactionCreationOptions.ForTimestampBoundReadOnly(null);
         Assert.Equal(TimestampBound.Strong, options.TimestampBound);
         Assert.Null(options.TransactionId);
+        Assert.Equal(TimestampBound.Strong, options.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadOnly, options.TransactionMode);
         Assert.False(options.IsDetached);
         Assert.False(options.IsSingleUse);
@@ -123,6 +127,7 @@ public void ForTimestampBoundReadOnly_Custom()
         var options = SpannerTransactionCreationOptions.ForTimestampBoundReadOnly(timestampBound);
         Assert.Equal(timestampBound, options.TimestampBound);
         Assert.Null(options.TransactionId);
+        Assert.Equal(timestampBound, options.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadOnly, options.TransactionMode);
         Assert.False(options.IsDetached);
         Assert.True(options.IsSingleUse);
@@ -145,13 +150,14 @@ public void FromReadOnlyTransactionId_NotNull()
         var options = SpannerTransactionCreationOptions.FromReadOnlyTransactionId(transactionId);
         Assert.Equal(transactionId, options.TransactionId);
         Assert.Null(options.TimestampBound);
+        Assert.Equal(TimestampBound.Strong, options.EffectiveTimestampBound);
         Assert.Equal(TransactionMode.ReadOnly, options.TransactionMode);
         Assert.True(options.IsDetached);
         Assert.False(options.IsSingleUse);
         Assert.False(options.IsPartitionedDml);
         Assert.False(options.ExcludeFromChangeStreams);
         Assert.Equal(IsolationLevel.Unspecified, options.IsolationLevel);
-        Assert.Null(options.GetTransactionOptions());
+        Assert.Equal(TimestampBound.Strong.ToTransactionOptions(), options.GetTransactionOptions());
         Assert.Equal(ReadLockMode.Unspecified, options.ReadLockMode);
     }
 

apis/Google.Cloud.Spanner.Data/Google.Cloud.Spanner.Data/SpannerConnection.cs

@@ -592,7 +592,7 @@ internal Task<SpannerTransaction> BeginTransactionAsyncImpl(
                     {
                         SessionName sessionName = SessionName.Parse(transactionCreationOptions.TransactionId.Session);
                         ByteString transactionIdBytes = ByteString.FromBase64(transactionCreationOptions.TransactionId.Id);
-                        var timestamp = transactionCreationOptions.TransactionId.TimestampBound?.Timestamp;
+                        var timestamp = transactionCreationOptions.EffectiveTimestampBound?.Timestamp;
                         var readTimestamp = timestamp.HasValue ? Protobuf.WellKnownTypes.Timestamp.FromDateTime(timestamp.Value) : null;
                         transaction = ManagedTransaction.FromTransaction(
                             _managedSession.Client, new Session { SessionName = sessionName }, transactionIdBytes, transactionCreationOptions.GetTransactionOptions(), readTimestamp);

apis/Google.Cloud.Spanner.Data/Google.Cloud.Spanner.Data/SpannerTransaction.cs

@@ -151,7 +151,7 @@ public int CommitTimeout
         /// </list>
         /// </para>
         /// </remarks>
-        public TimestampBound TimestampBound => _creationOptions.TimestampBound ?? _creationOptions.TransactionId?.TimestampBound;
+        public TimestampBound TimestampBound => _creationOptions.EffectiveTimestampBound;
 
         /// <inheritdoc />
         protected override DbConnection DbConnection => SpannerConnection;

apis/Google.Cloud.Spanner.Data/Google.Cloud.Spanner.Data/SpannerTransactionCreationOptions.cs

@@ -62,6 +62,9 @@ public sealed class SpannerTransactionCreationOptions
     /// </summary>
     public TransactionId TransactionId { get; }
 
+    internal TimestampBound EffectiveTimestampBound => TimestampBound ?? TransactionId?.TimestampBound;
+    private TransactionOptions EffectiveTimestampBoundTxnOptions => EffectiveTimestampBound?.ToTransactionOptions();
+
     /// <summary>
     /// Whether these options should result in a detached transaction or in one that's tracked by a session pool.
     /// This will always be true when <see cref="TransactionId"/> is set. Otherwise it will be false unless explicitly
@@ -206,9 +209,15 @@ public static SpannerTransactionCreationOptions FromReadOnlyTransactionId(Transa
     /// </summary>
     internal TransactionOptions GetTransactionOptions()
     {
-        var options = IsPartitionedDml ? new TransactionOptions { PartitionedDml = new PartitionedDml() } :
-            TransactionMode == TransactionMode.ReadWrite ? new TransactionOptions { ReadWrite = new ReadWrite() } :
-            TimestampBound?.ToTransactionOptions();
+        TransactionOptions options = this switch
+        {
+            { IsPartitionedDml: true } => new TransactionOptions { PartitionedDml = new PartitionedDml() },
+            { TransactionMode: TransactionMode.ReadWrite } => new TransactionOptions { ReadWrite = new ReadWrite() },
+            { EffectiveTimestampBoundTxnOptions: var txnOptions } when txnOptions is not null => txnOptions,
+            { TransactionId: var txnId } when txnId is not null => new TransactionOptions { ReadOnly = new ReadOnly() },
+            _ => null
+        };
+
         if (options is not null)
         {
             options.ExcludeTxnFromChangeStreams = ExcludeFromChangeStreams;
@@ -233,11 +242,11 @@ internal TransactionOptions GetTransactionOptions()
         return options;
     }
 
-    /// <summary>
-    /// Returns a new instance identical to this one except for the value of <see cref="IsDetached"/>.
-    /// If <see cref="TransactionId"/> is set, <see cref="IsDetached"/> cannot be false.
-    /// </summary>
-    public SpannerTransactionCreationOptions WithIsDetached(bool isDetached) =>
+/// <summary>
+/// Returns a new instance identical to this one except for the value of <see cref="IsDetached"/>.
+/// If <see cref="TransactionId"/> is set, <see cref="IsDetached"/> cannot be false.
+/// </summary>
+public SpannerTransactionCreationOptions WithIsDetached(bool isDetached) =>
         isDetached == IsDetached ? this : new SpannerTransactionCreationOptions(TimestampBound, TransactionId, isDetached, IsSingleUse, IsPartitionedDml, ExcludeFromChangeStreams, IsolationLevel, ReadLockMode);
 
     /// <summary>