Add table and view metadata messges (#296)

* Add SMO table property lookup event

* Fix a couple bugs in column metadata

* Add GetView metadata message

src/Microsoft.SqlTools.ServiceLayer/Metadata/Contracts/ColumnMetadata.cs

@@ -0,0 +1,112 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Data;
+using Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts;
+using Microsoft.SqlTools.Utility;
+
+namespace Microsoft.SqlTools.ServiceLayer.Metadata
+{
+    /// <summary>
+    /// ColumnMetadata class
+    /// </summary>
+    public class ColumnMetadata
+    {
+        /// <summary>
+        /// Constructs a simple edit column metadata provider
+        /// </summary>
+        public ColumnMetadata()
+        {
+            HasExtendedProperties = false;
+        }
+
+        #region Basic Properties (properties provided by SMO)
+
+        /// <summary>
+        /// If set, this is a string representation of the default value. If set to null, then the
+        /// column does not have a default value.
+        /// </summary>
+        public string DefaultValue { get; set; }
+
+        /// <summary>
+        /// Escaped identifier for the name of the column
+        /// </summary>
+        public string EscapedName { get; set; }
+
+        /// <summary>
+        /// Whether or not the column is computed
+        /// </summary>
+        public bool IsComputed { get; set; }
+
+        /// <summary>
+        /// Whether or not the column is deterministically computed
+        /// </summary>
+        public bool IsDeterministic { get; set; }
+
+        /// <summary>
+        /// Whether or not the column is an identity column
+        /// </summary>
+        public bool IsIdentity { get; set; }
+
+        /// <summary>
+        /// The ordinal ID of the column
+        /// </summary>
+        public int Ordinal { get; set; }
+
+        #endregion
+
+        #region Extended Properties (properties provided by SqlClient)
+
+        // public DbColumnWrapper DbColumn { get; private set; }
+
+        /// <summary>
+        /// Whether or not the column has extended properties
+        /// </summary>
+        public bool HasExtendedProperties { get; private set; }
+
+        /// <summary>
+        /// Whether or not the column is calculated on the server side. This could be a computed
+        /// column or a identity column.
+        /// </summary>
+        public bool? IsCalculated { get; private set; }
+
+        /// <summary>
+        /// Whether or not the column is used in a key to uniquely identify a row
+        /// </summary>
+        public bool? IsKey { get; private set; }
+
+        /// <summary>
+        /// Whether or not the column can be trusted for uniqueness
+        /// </summary>
+        public bool? IsTrustworthyForUniqueness { get; private set; }
+
+        #endregion
+
+        /// <summary>
+        /// Extracts extended column properties from the database columns from SQL Client
+        /// </summary>
+        /// <param name="dbColumn">The column information provided by SQL Client</param>
+        public void Extend(DbColumnWrapper dbColumn)
+        {
+            Validate.IsNotNull(nameof(dbColumn), dbColumn);
+
+            // DbColumn = dbColumn;
+
+            // A column is trustworthy for uniqueness if it can be updated or it has an identity
+            // property. If both of these are false (eg, timestamp) we can't trust it to uniquely
+            // identify a row in the table
+            IsTrustworthyForUniqueness = dbColumn.IsUpdatable || dbColumn.IsIdentity.HasTrue();
+
+            // A key column is determined by whether it is a key
+            IsKey = dbColumn.IsKey;
+
+            // A column is calculated if it is identity, computed, or otherwise not updatable
+            IsCalculated = IsIdentity || IsComputed || !dbColumn.IsUpdatable;
+
+            // Mark the column as extended
+            HasExtendedProperties = true;
+        }
+    }
+}

src/Microsoft.SqlTools.ServiceLayer/Metadata/Contracts/TableMetadata.cs

@@ -0,0 +1,85 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System.Linq;
+using Microsoft.SqlTools.ServiceLayer.QueryExecution.Contracts;
+using Microsoft.SqlTools.Utility;
+
+namespace Microsoft.SqlTools.ServiceLayer.Metadata
+{
+    /// <summary>
+    /// Provides metadata about the table or view being edited
+    /// </summary>
+    public class TableMetadata
+    {
+        /// <summary>
+        /// Constructs a simple edit table metadata provider
+        /// </summary>
+        public TableMetadata()
+        {
+            HasExtendedProperties = false;
+        }
+
+        #region Basic Properties (properties provided by SMO)
+
+        /// <summary>
+        /// List of columns in the object being edited
+        /// </summary>
+        public ColumnMetadata[] Columns { get; set; }
+
+        /// <summary>
+        /// Full escaped multipart identifier for the object being edited
+        /// </summary>
+        public string EscapedMultipartName { get; set; }
+
+        /// <summary>
+        /// Whether or not the object being edited is memory optimized
+        /// </summary>
+        public bool IsMemoryOptimized { get; set; }
+
+        #endregion
+
+        #region Extended Properties (properties provided by SqlClient)
+
+        /// <summary>
+        /// Whether or not the table has had extended properties added to it
+        /// </summary>
+        public bool HasExtendedProperties { get; private set; }
+
+        /// <summary>
+        /// List of columns that are used to uniquely identify a row
+        /// </summary>
+        public ColumnMetadata[] KeyColumns { get; private set; }
+
+        #endregion
+
+        /// <summary>
+        /// Extracts extended column properties from the database columns from SQL Client
+        /// </summary>
+        /// <param name="dbColumnWrappers">The column information provided by SQL Client</param>
+        public void Extend(DbColumnWrapper[] dbColumnWrappers)
+        {
+            Validate.IsNotNull(nameof(dbColumnWrappers), dbColumnWrappers);
+
+            // Iterate over the column wrappers and improve the columns we have
+            for (int i = 0; i < Columns.Length; i++)
+            {
+                Columns[i].Extend(dbColumnWrappers[i]);
+            }
+
+            // Determine what the key columns are
+            KeyColumns = Columns.Where(c => c.IsKey.HasTrue()).ToArray();
+            if (KeyColumns.Length == 0)
+            {
+                // We didn't find any explicit key columns. Instead, we'll use all columns that are
+                // trustworthy for uniqueness (usually all the columns)
+                KeyColumns = Columns.Where(c => c.IsTrustworthyForUniqueness.HasTrue()).ToArray();
+            }
+
+            // Mark that the table is now extended
+            HasExtendedProperties = true;
+        }
+    }
+}

src/Microsoft.SqlTools.ServiceLayer/Metadata/Contracts/TableMetadataRequest.cs

@@ -0,0 +1,33 @@
+//
+// 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.Hosting.Protocol.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.Metadata.Contracts
+{
+    public class TableMetadataParams 
+    {
+        public string OwnerUri { get; set; }        
+
+        public string Schema { get; set; }  
+
+        public string ObjectName { get; set; }  
+    }
+
+    public class TableMetadataResult
+    {
+        public ColumnMetadata[] Columns { get; set; }
+    }
+
+    /// <summary>
+    /// Retreive metadata for the table described in the TableMetadataParams value
+    /// </summary>
+    public class TableMetadataRequest
+    {
+        public static readonly
+            RequestType<TableMetadataParams, TableMetadataResult> Type =
+                RequestType<TableMetadataParams, TableMetadataResult>.Create("metadata/table");
+    }
+}

src/Microsoft.SqlTools.ServiceLayer/Metadata/Contracts/ViewMetadataRequest.cs

@@ -0,0 +1,21 @@
+//
+// 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.Hosting.Protocol.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.Metadata.Contracts
+{
+    /// <summary>
+    /// Retreive metadata for the view described in the TableMetadataParams value.
+    /// This message reuses the table metadata params and result since the exchanged
+    /// data is the same.
+    /// </summary>
+    public class ViewMetadataRequest
+    {
+        public static readonly
+            RequestType<TableMetadataParams, TableMetadataResult> Type =
+                RequestType<TableMetadataParams, TableMetadataResult>.Create("metadata/view");
+    }
+}

src/Microsoft.SqlTools.ServiceLayer/Metadata/MetadataService.cs

@@ -53,6 +53,8 @@ namespace Microsoft.SqlTools.ServiceLayer.Metadata
         public void InitializeService(ServiceHost serviceHost)
         {
             serviceHost.SetRequestHandler(MetadataListRequest.Type, HandleMetadataListRequest);
+            serviceHost.SetRequestHandler(TableMetadataRequest.Type, HandleGetTableRequest);
+            serviceHost.SetRequestHandler(ViewMetadataRequest.Type, HandleGetViewRequest);
         }
 
         /// <summary>
@@ -87,6 +89,62 @@ namespace Microsoft.SqlTools.ServiceLayer.Metadata
             }
         }
 
+        /// <summary>
+        /// Handle a table metadata query request
+        /// </summary>        
+        internal static async Task HandleGetTableRequest(
+            TableMetadataParams metadataParams,
+            RequestContext<TableMetadataResult> requestContext)
+        {
+            await HandleGetTableOrViewRequest(metadataParams, "table", requestContext);
+        }
+
+        /// <summary>
+        /// Handle a view metadata query request
+        /// </summary>        
+        internal static async Task HandleGetViewRequest(
+            TableMetadataParams metadataParams,
+            RequestContext<TableMetadataResult> requestContext)
+        {
+            await HandleGetTableOrViewRequest(metadataParams, "view", requestContext);
+        }
+
+        /// <summary>
+        /// Handle a table pr view metadata query request
+        /// </summary>        
+        private static async Task HandleGetTableOrViewRequest(
+            TableMetadataParams metadataParams,
+            string objectType,
+            RequestContext<TableMetadataResult> requestContext)
+        {
+            try
+            {
+                ConnectionInfo connInfo;
+                MetadataService.ConnectionServiceInstance.TryFindConnection(
+                    metadataParams.OwnerUri,
+                    out connInfo);
+
+                ColumnMetadata[] metadata = null;
+                if (connInfo != null) 
+                {
+                    SqlConnection sqlConn = OpenMetadataConnection(connInfo);                    
+                    TableMetadata table = new SmoMetadataFactory().GetObjectMetadata(
+                        sqlConn, metadataParams.Schema, 
+                        metadataParams.ObjectName, objectType);
+                    metadata = table.Columns;               
+                }
+
+                await requestContext.SendResult(new TableMetadataResult
+                {
+                    Columns = metadata    
+                });
+            }
+            catch (Exception ex)
+            {
+                await requestContext.SendError(ex.ToString());
+            }
+        }
+
         /// <summary>
         /// Create a SqlConnection to use for querying metadata
         /// </summary>
@@ -162,6 +220,6 @@ namespace Microsoft.SqlTools.ServiceLayer.Metadata
                     }
                 }
             }
-        }        
+        }
     }
 }

src/Microsoft.SqlTools.ServiceLayer/Metadata/SmoMetadataFactory.cs

@@ -0,0 +1,122 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System;
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Data.SqlClient;
+using Microsoft.SqlServer.Management.Common;
+using Microsoft.SqlServer.Management.Smo;
+using Microsoft.SqlTools.ServiceLayer.Connection.ReliableConnection;
+using Microsoft.SqlTools.ServiceLayer.Utility;
+
+namespace Microsoft.SqlTools.ServiceLayer.Metadata
+{
+    /// <summary>
+    /// Interface for a factory that generates metadata for an object to edit
+    /// </summary>
+    public interface IMetadataFactory
+    {
+        /// <summary>
+        /// Generates a edit-ready metadata object
+        /// </summary>
+        /// <param name="connection">Connection to use for getting metadata</param>
+        /// <param name="objectName">Name of the object to return metadata for</param>
+        /// <param name="objectType">Type of the object to return metadata for</param>
+        /// <returns>Metadata about the object requested</returns>
+        TableMetadata GetObjectMetadata(DbConnection connection, string schemaName, string objectName, string objectType);
+    }
+
+    /// <summary>
+    /// Factory that generates metadata using a combination of SMO and SqlClient metadata
+    /// </summary>
+    public class SmoMetadataFactory : IMetadataFactory
+    {
+        /// <summary>
+        /// Generates a edit-ready metadata object using SMO
+        /// </summary>
+        /// <param name="connection">Connection to use for getting metadata</param>
+        /// <param name="objectName">Name of the object to return metadata for</param>
+        /// <param name="objectType">Type of the object to return metadata for</param>
+        /// <returns>Metadata about the object requested</returns>
+        public TableMetadata GetObjectMetadata(DbConnection connection, string schemaName, string objectName, string objectType)
+        {
+            // Get a connection to the database for SMO purposes
+            SqlConnection sqlConn = connection as SqlConnection;
+            if (sqlConn == null)
+            {
+                // It's not actually a SqlConnection, so let's try a reliable SQL connection
+                ReliableSqlConnection reliableConn = connection as ReliableSqlConnection;
+                if (reliableConn == null)
+                {
+                    // If we don't have connection we can use with SMO, just give up on using SMO
+                    return null;
+                }
+
+                // We have a reliable connection, use the underlying connection
+                sqlConn = reliableConn.GetUnderlyingConnection();
+            }
+
+            // Connect with SMO and get the metadata for the table
+            Server server = new Server(new ServerConnection(sqlConn));
+            Database database = server.Databases[sqlConn.Database];
+            TableViewTableTypeBase smoResult;
+            switch (objectType.ToLowerInvariant())
+            {
+                case "table":                    
+                    Table table = string.IsNullOrEmpty(schemaName) ? new Table(database, objectName) : new Table(database, objectName, schemaName);
+                    table.Refresh();
+                    smoResult = table;
+                    break;
+                case "view":
+                    View view = string.IsNullOrEmpty(schemaName) ? new View(database, objectName) : new View(database, objectName, schemaName);
+                    view.Refresh();
+                    smoResult = view;
+                    break;
+                default:
+                    throw new ArgumentOutOfRangeException(nameof(objectType), SR.EditDataUnsupportedObjectType(objectType));
+            }
+            if (smoResult == null)
+            {
+                throw new ArgumentOutOfRangeException(nameof(objectName), SR.EditDataObjectMetadataNotFound);
+            }
+
+            // Generate the edit column metadata
+            List<ColumnMetadata> editColumns = new List<ColumnMetadata>();
+            for (int i = 0; i < smoResult.Columns.Count; i++)
+            {
+                Column smoColumn = smoResult.Columns[i];
+
+                // The default value may be escaped
+                string defaultValue = smoColumn.DefaultConstraint == null
+                    ? null
+                    : SqlScriptFormatter.UnwrapLiteral(smoColumn.DefaultConstraint.Text);
+
+                ColumnMetadata column = new ColumnMetadata
+                {
+                    DefaultValue = defaultValue,
+                    EscapedName = SqlScriptFormatter.FormatIdentifier(smoColumn.Name),
+                    Ordinal = i,
+                };
+                editColumns.Add(column);
+            }
+
+            // Only tables can be memory-optimized
+            Table smoTable = smoResult as Table;
+            bool isMemoryOptimized = smoTable != null && smoTable.IsMemoryOptimized;
+
+            // Escape the parts of the name
+            string[] objectNameParts = {smoResult.Schema, smoResult.Name};
+            string escapedMultipartName = SqlScriptFormatter.FormatMultipartIdentifier(objectNameParts);
+
+            return new TableMetadata
+            {
+                Columns = editColumns.ToArray(),
+                EscapedMultipartName = escapedMultipartName,
+                IsMemoryOptimized = isMemoryOptimized,
+            };
+        }
+    }
+}