Progressive Results Part 2: Result Completion Event (#134)

The main change in this pull request is to add a new event that will be fired upon completion of a resultset but before the completion of a batch. This event will only fire if a resultset is available and generated.

Changes:
* ConnectionService - Slight changes to enable mocking, cleanup 
* Batch - Moving summary generation into ResultSet class, adding generation of ordinals for resultset and locking of result set list (which needs further refinement, but would be outside scope of this change)
* Adding new event and associated parameters for completion of a resultset. Params return the resultset summary
* Adding logic for assigning the event a handler in the query execution service
* Adding unit tests for testing the new event /making sure the existing tests work
* Refactoring some private properties into member variables

* Refactor to remove SectionData class in favor of BufferRange

* Adding callback for batch completion that will let the extension know that a batch has completed execution

* Refactoring to make progressive results work as per async query execution

* Allowing retrieval of batch results while query is in progress

* reverting global.json, whoops

* Adding a few missing comments, and fixing a couple code style bugs

* Using SelectionData everywhere again

* One more missing comment

* Adding new notification type for result set completion

* Plumbing event for result set completion

* Unit tests for result set events

This includes a fairly substantial change to create a mock of the
ConnectionService and to create separate memorystream storage arrays. It
preserves more correct behavior with a integration test, fixes an issue
where the test db reader will return n-1 rows because the Reliable
Connection Helper steals a record.

* Adding locking to ResultSets for thread safety

* Adding/fixing unit tests

* Adding batch ID to result set summary

test/Microsoft.SqlTools.ServiceLayer.Test/QueryExecution/Execution/ResultSetTests.cs

@@ -22,14 +22,20 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
         {
             // If:
             // ... I create a new result set with a valid db data reader
-
             DbDataReader mockReader = GetReader(null, false, string.Empty);
-            ResultSet resultSet = new ResultSet(mockReader, Common.GetFileStreamFactory(new Dictionary<string, byte[]>()));
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, Common.GetFileStreamFactory(new Dictionary<string, byte[]>()));
 
             // Then:
             // ... There should not be any data read yet
             Assert.Null(resultSet.Columns);
             Assert.Equal(0, resultSet.RowCount);
+            Assert.Equal(Common.Ordinal, resultSet.Id);
+
+            // ... The summary should include the same info
+            Assert.Null(resultSet.Summary.ColumnInfo);
+            Assert.Equal(0, resultSet.Summary.RowCount);
+            Assert.Equal(Common.Ordinal, resultSet.Summary.Id);
+            Assert.Equal(Common.Ordinal, resultSet.Summary.BatchId);
         }
 
         [Fact]
@@ -39,29 +45,45 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             // ... I create a new result set without a reader
             // Then:
             // ... It should throw an exception
-            Assert.Throws<ArgumentNullException>(() => new ResultSet(null, null));
+            Assert.Throws<ArgumentNullException>(() => new ResultSet(null, Common.Ordinal, Common.Ordinal, null));
 
         }
 
         [Fact]
         public async Task ReadToEndSuccess()
         {
+            // Setup: Create a callback for resultset completion
+            ResultSetSummary resultSummaryFromCallback = null;
+            ResultSet.ResultSetAsyncEventHandler callback = r =>
+            {
+                resultSummaryFromCallback = r.Summary;
+                return Task.FromResult(0);
+            };
+
             // If:
             // ... I create a new resultset with a valid db data reader that has data
             // ... and I read it to the end
             DbDataReader mockReader = GetReader(new [] {Common.StandardTestData}, false, Common.StandardQuery);
             var fileStreamFactory = Common.GetFileStreamFactory(new Dictionary<string, byte[]>());
-            ResultSet resultSet = new ResultSet(mockReader, fileStreamFactory);
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, fileStreamFactory);
+            resultSet.ResultCompletion += callback;
             await resultSet.ReadResultToEnd(CancellationToken.None);
 
             // Then:
             // ... The columns should be set
             // ... There should be rows to read back
             Assert.NotNull(resultSet.Columns);
-            Assert.NotEmpty(resultSet.Columns);
+            Assert.Equal(Common.StandardColumns, resultSet.Columns.Length);
             Assert.Equal(Common.StandardRows, resultSet.RowCount);
-        }
 
+            // ... The summary should have the same info
+            Assert.NotNull(resultSet.Summary.ColumnInfo);
+            Assert.Equal(Common.StandardColumns, resultSet.Summary.ColumnInfo.Length);
+            Assert.Equal(Common.StandardRows, resultSet.Summary.RowCount);
+
+            // ... The callback for result set completion should have been fired
+            Assert.NotNull(resultSummaryFromCallback);
+        }
         
         [Theory]
         [InlineData("JSON")]
@@ -78,12 +100,21 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             }
             Dictionary<string, string>[][] dataSets = {data.ToArray()};
 
+            // ... Create a callback for resultset completion
+            ResultSetSummary resultSummary = null;
+            ResultSet.ResultSetAsyncEventHandler callback = r =>
+            {
+                resultSummary = r.Summary;
+                return Task.FromResult(0);
+            };
+
             // If:
             // ... I create a new resultset with a valid db data reader that is FOR XML/JSON
             // ... and I read it to the end
             DbDataReader mockReader = GetReader(dataSets, false, Common.StandardQuery);
             var fileStreamFactory = Common.GetFileStreamFactory(new Dictionary<string, byte[]>());
-            ResultSet resultSet = new ResultSet(mockReader, fileStreamFactory);
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, fileStreamFactory);
+            resultSet.ResultCompletion += callback;
             await resultSet.ReadResultToEnd(CancellationToken.None);
 
             // Then:
@@ -93,6 +124,9 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             Assert.Equal(1, resultSet.Columns.Length);
             Assert.Equal(1, resultSet.RowCount);
 
+            // ... The callback should have been called
+            Assert.NotNull(resultSummary);
+
             // If:
             // ... I attempt to read back the results
             // Then: 
@@ -108,7 +142,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             // ... I create a new result set with a valid db data reader without executing it
             DbDataReader mockReader = GetReader(null, false, string.Empty);
             var fileStreamFactory = Common.GetFileStreamFactory(new Dictionary<string, byte[]>());
-            ResultSet resultSet = new ResultSet(mockReader, fileStreamFactory);
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, fileStreamFactory);
 
             // Then:
             // ... Attempting to read a subset should fail miserably
@@ -126,7 +160,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             // ... And execute the result
             DbDataReader mockReader = GetReader(new[] {Common.StandardTestData}, false, Common.StandardQuery);
             var fileStreamFactory = Common.GetFileStreamFactory(new Dictionary<string, byte[]>());
-            ResultSet resultSet = new ResultSet(mockReader, fileStreamFactory);
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, fileStreamFactory);
             await resultSet.ReadResultToEnd(CancellationToken.None);
 
             // ... And attempt to get a subset with invalid parameters
@@ -147,7 +181,7 @@ namespace Microsoft.SqlTools.ServiceLayer.Test.QueryExecution.Execution
             // ... And execute the result set
             DbDataReader mockReader = GetReader(new[] { Common.StandardTestData }, false, Common.StandardQuery);
             var fileStreamFactory = Common.GetFileStreamFactory(new Dictionary<string, byte[]>());
-            ResultSet resultSet = new ResultSet(mockReader, fileStreamFactory);
+            ResultSet resultSet = new ResultSet(mockReader, Common.Ordinal, Common.Ordinal, fileStreamFactory);
             await resultSet.ReadResultToEnd(CancellationToken.None);
 
             // ... And attempt to get a subset with valid number of rows