public void TestDataReaderReadException() { // Setup two data readers from shards var mockReader1 = new MockSqlDataReader("Reader1"); var mockReader2 = new MockSqlDataReader("Reader2"); bool movedOnToNextReader = false; int invokeCount = 1; Func <MockSqlDataReader, Task <bool> > ExecuteOnReadAsync = (r) => { return(Task.Run <bool>(() => { // First reader throws an exception when Read if (r.Name == "Reader1") { if (invokeCount == 2) { throw new InvalidOperationException(); } } else { movedOnToNextReader = true; } return true; })); }; Action <MockSqlDataReader> ExecuteOnGetColumn = (r) => { if (r.Name == "Reader1") { throw new InvalidOperationException(); } }; mockReader1.ExecuteOnReadAsync = ExecuteOnReadAsync; mockReader1.ExecuteOnGetColumn = ExecuteOnGetColumn; mockReader2.ExecuteOnReadAsync = ExecuteOnReadAsync; var labeledDataReaders = new LabeledDbDataReader[2]; labeledDataReaders[0] = new LabeledDbDataReader(mockReader1, new ShardLocation("test", "Shard1"), new MockSqlCommand() { Connection = new MockSqlConnection("", () => { }) }); labeledDataReaders[1] = new LabeledDbDataReader(mockReader2, new ShardLocation("test", "Shard2"), new MockSqlCommand() { Connection = new MockSqlConnection("", () => { }) }); // Create the MultiShardDataReader var mockMultiShardCmd = MultiShardCommand.Create(null, "test"); var multiShardDataReader = new MultiShardDataReader(mockMultiShardCmd, labeledDataReaders, MultiShardExecutionPolicy.PartialResults, false); // Validate that if an exception is thrown when reading a column, // it is propagated back to the user try { multiShardDataReader.Read(); invokeCount++; multiShardDataReader.GetInt32(0); } catch (Exception ex) { Assert.IsTrue(ex is InvalidOperationException, "Expected InvalidOperationException!"); } // Validate that we didn't automatically move on to the next reader when we // hit an exception whilst reading the column and that // an exception from a second Read() call is stored and the reader is closed multiShardDataReader.Read(); Assert.AreEqual(multiShardDataReader.MultiShardExceptions.Count, 1, "Expected exception to be recorded"); Assert.IsTrue(mockReader1.IsClosed, "Expected reader to be closed!"); // Validate we immediately moved on to the next reader multiShardDataReader.Read(); Assert.IsTrue(movedOnToNextReader, "Should've moved on to next reader"); }
public void TestAddDataReaderWithNullSchema() { // Creates a MultiShardDataReader and verifies that the right exception is thrown Func <LabeledDbDataReader[], bool> createMultiShardReader = (readers) => { bool hitNullSchemaException = false; try { var mockMultiShardCmd = MultiShardCommand.Create(null, "test"); var multiShardDataReader = new MultiShardDataReader(mockMultiShardCmd, readers, MultiShardExecutionPolicy.PartialResults, false, readers.Length); } catch (MultiShardDataReaderInternalException ex) { hitNullSchemaException = ex.Message.Contains("null schema"); } return(hitNullSchemaException); }; var labeledDataReaders = new LabeledDbDataReader[10]; // Create a few mock readers. All with a null schema for (int i = 0; i < labeledDataReaders.Length; i++) { var mockReader = new MockSqlDataReader(string.Format("Reader{0}", i), null /* Null schema */); labeledDataReaders[i] = new LabeledDbDataReader(mockReader, new ShardLocation("test", string.Format("Shard{0}", i)), new MockSqlCommand() { Connection = new MockSqlConnection("", () => { }) }); } // Case #1 bool hitException = createMultiShardReader(labeledDataReaders); Assert.IsFalse(hitException, "Unexpected exception! All readers have a null schema."); // Case #2 for (int i = 0; i < labeledDataReaders.Length; i++) { MockSqlDataReader mockReader = (MockSqlDataReader)labeledDataReaders[i].DbDataReader; mockReader.Open(); if (i > labeledDataReaders.Length / 2) { mockReader.DataTable = new DataTable(); } } hitException = createMultiShardReader(labeledDataReaders); Assert.IsTrue(hitException, "Exception not hit! Second half of readers don't have a null schema!"); // Case #3 for (int i = 0; i < labeledDataReaders.Length; i++) { MockSqlDataReader mockReader = (MockSqlDataReader)labeledDataReaders[i].DbDataReader; mockReader.Open(); if (i < labeledDataReaders.Length / 2) { mockReader.DataTable = new DataTable(); } else { mockReader.DataTable = null; } } hitException = createMultiShardReader(labeledDataReaders); Assert.IsTrue(hitException, "Exception not hit! First half of readers don't have a null schema!"); }
public void TestShardCommandRetryConnectionReopen() { var retryPolicy = new RetryPolicy(4, TimeSpan.FromMilliseconds(100), TimeSpan.FromSeconds(10), TimeSpan.FromMilliseconds(100)); var shardConnections = new List <Tuple <ShardLocation, DbConnection> >(); // Callback to execute when the MockCommand is invoked Func <CancellationToken, MockSqlCommand, DbDataReader> ExecuteReaderFunc = null; // Number of times each command has been retried var commandRetryCounts = new int[10]; // Create ten mocked connections, // a few of them will throw an exception on Open // and the rest will throw an exception on command execution upto 2 retries // At the end, all commands should complete successfully. for (int i = 0; i < 10; i++) { string database = string.Format("{0}", i); int j = i; int retryCount = 0; Action executeOnOpen = () => { if (j < 5) { if (retryCount < 3) { retryCount++; throw new TimeoutException(); } } }; var mockCon = new MockSqlConnection(database, executeOnOpen); shardConnections.Add(new Tuple <ShardLocation, DbConnection>(new ShardLocation("Shard", database), mockCon)); } ExecuteReaderFunc = (t, r) => { int index = Int32.Parse(((MockSqlConnection)(r.Connection)).ConnectionString); if (r.Connection.State == ConnectionState.Closed) { throw new InvalidOperationException("Command shouldn't be executed on a closed connection!"); } if (index > 5 && commandRetryCounts[index] < 3) { commandRetryCounts[index]++; r.RetryCount++; r.Connection.Close(); throw new TimeoutException(); } else { var mockRdr = new MockSqlDataReader(); mockRdr.ExecuteOnReadAsync = (rdr) => { return(Task.Run <bool>(() => { bool isClosed = rdr.IsClosed; rdr.Close(); return !isClosed; })); }; return(mockRdr); } }; var mockCmd = new MockSqlCommand(); mockCmd.ExecuteReaderFunc = ExecuteReaderFunc; mockCmd.CommandText = "select 1"; using (var conn = new MultiShardConnection(shardConnections)) { using (var cmd = MultiShardCommand.Create(conn, mockCmd, 300)) { cmd.RetryPolicy = retryPolicy; cmd.ExecutionPolicy = MultiShardExecutionPolicy.PartialResults; using (var reader = cmd.ExecuteReaderAsync().Result) { // Validate that we successfully received a reader // from each one of the shards int readerCount = 0; while (reader.Read()) { readerCount++; } Assert.AreEqual(10, readerCount, "Expected 10 readers!"); } } } }