Refactor error messages (#122)

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

@@ -84,6 +84,17 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts
         public string Messages { get; set; }
     }
 
+    /// <summary>
+    /// Error object for save result 
+    /// </summary>
+    public class SaveResultRequestError
+    {
+        /// <summary>
+        /// Error message 
+        /// </summary>
+        public string message { get; set; }
+    }
+
     /// <summary>
     /// Request type to save results as CSV
     /// </summary>

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/QueryExecutionService.cs

@@ -280,7 +280,7 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution
                 SaveResults.AsyncSaveEventHandler errorHandler = async message =>
                 {
                     selectedResultSet.RemoveSaveTask(saveParams.FilePath);
-                    await requestContext.SendError(message);
+                    await requestContext.SendError(new SaveResultRequestError { message = message });
                 };
                 saveAsCsv.SaveFailed += errorHandler;
 
@@ -323,7 +323,7 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution
                 SaveResults.AsyncSaveEventHandler errorHandler = async message =>
                 {
                     selectedResultSet.RemoveSaveTask(saveParams.FilePath);
-                    await requestContext.SendError(message);
+                    await requestContext.SendError(new SaveResultRequestError { message = message });
                 };
                 saveAsJson.SaveFailed += errorHandler;
 

src/Microsoft.SqlTools.ServiceLayer/QueryExecution/SaveResults.cs

@@ -222,7 +222,7 @@ namespace Microsoft.SqlTools.ServiceLayer.QueryExecution
                     }
                     if (SaveFailed != null)
                     {
-                        await SaveFailed(ex.ToString());
+                        await SaveFailed(ex.Message);
                     }
                 }
             });