Feature: Progressive Messages (#208)

This change is a reworking of the way that messages are sent to clients from the service layer. It is also a reworking of the protocol to ensure that all formulations of query send back events to the client in a deterministic ordering. To support the first change:
* Added a new event that will be sent when a message is generated
* Messages now indicate which Batch (if any) generated them
* Messages now indicate if they were error level
* Removed message storage in Batch objects and BatchSummary objects
* Batch objects no longer have error state

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/BatchSummary.cs

@@ -25,11 +25,6 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         /// </summary>
         public string ExecutionStart { get; set; }
 
-        /// <summary>
-        /// Whether or not the batch was successful. True indicates errors, false indicates success
-        /// </summary>
-        public bool HasError { get; set; }
-
         /// <summary>
         /// The ID of the result set within the query results
         /// </summary>
@@ -40,11 +35,6 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         /// </summary>
         public SelectionData Selection { get; set; }
 
-        /// <summary>
-        /// Any messages that came back from the server during execution of the batch
-        /// </summary>
-        public ResultMessage[] Messages { get; set; }
-
         /// <summary>
         /// The summaries of the result sets inside the batch
         /// </summary>

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/QueryExecuteCompleteNotification.cs

@@ -21,11 +21,6 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         /// Summaries of the result sets that were returned with the query
         /// </summary>
         public BatchSummary[] BatchSummaries { get; set; }
-
-        /// <summary>
-        /// Error message, if any
-        /// </summary>
-        public string Message { get; set; }
     }
 
     public class QueryExecuteCompleteEvent

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/QueryExecuteMessageNotification.cs

@@ -0,0 +1,32 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using Microsoft.SqlTools.ServiceLayer.Hosting.Protocol.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
+{
+    /// <summary>
+    /// Parameters to be sent back with a message notification
+    /// </summary>
+    public class QueryExecuteMessageParams
+    {
+        /// <summary>
+        /// URI for the editor that owns the query
+        /// </summary>
+        public string OwnerUri { get; set; }
+
+        /// <summary>
+        /// The message that is being returned
+        /// </summary>
+        public ResultMessage Message { get; set; }
+    }
+
+    public class QueryExecuteMessageEvent
+    {
+        public static readonly
+            EventType<QueryExecuteMessageParams> Type =
+            EventType<QueryExecuteMessageParams>.Create("query/message");
+    }
+}

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/QueryExecuteRequest.cs

@@ -28,10 +28,6 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
     /// </summary>
     public class QueryExecuteResult
     {
-        /// <summary>
-        /// Informational messages from the query runner. Optional, can be set to null.
-        /// </summary>
-        public string Messages { get; set; }
     }
 
     public class QueryExecuteRequest

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/Contracts/ResultMessage.cs

@@ -12,6 +12,17 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
     /// </summary>
     public class ResultMessage
     {
+        /// <summary>
+        /// ID of the batch that generated this message. If null, this message
+        /// was not generated as part of a batch
+        /// </summary>
+        public int? BatchId { get; set; }
+
+        /// <summary>
+        /// Whether or not this message is an error
+        /// </summary>
+        public bool IsError { get; set; }
+
         /// <summary>
         /// Timestamp of the message
         /// Stored in UTC ISO 8601 format; should be localized before displaying to any user
@@ -23,20 +34,13 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         /// </summary>
         public string Message { get; set; }
 
-        /// <summary>
-        /// Full constructor
-        /// </summary>
-        public ResultMessage(string timeStamp, string message)
-        {
-            Time = timeStamp;
-            Message = message;
-        }
-
         /// <summary>
         /// Constructor with default "Now" time
         /// </summary>
-        public ResultMessage(string message)
+        public ResultMessage(string message, bool isError, int? batchId)
         {
+            BatchId = batchId;
+            IsError = isError;
             Time = DateTime.Now.ToString("o");
             Message = message;
         }