extend the list databases request (#951)

* extend the list databases request

* reuse databaseInfo and refactor

* fix typo

src/Microsoft.SqlTools.ServiceLayer/Connection/ConnectionService.cs

@@ -910,41 +910,8 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection
             {
                 throw new Exception(SR.ConnectionServiceListDbErrorNotConnected(owner));
             }
-            ConnectionDetails connectionDetails = info.ConnectionDetails.Clone();
-
-            // Connect to master and query sys.databases
-            connectionDetails.DatabaseName = "master";
-            var connection = this.ConnectionFactory.CreateSqlConnection(BuildConnectionString(connectionDetails), connectionDetails.AzureAccountToken);
-            connection.Open();
-
-            List<string> results = new List<string>();
-            var systemDatabases = new[] { "master", "model", "msdb", "tempdb" };
-            using (DbCommand command = connection.CreateCommand())
-            {
-                command.CommandText = @"SELECT name FROM sys.databases WHERE state_desc='ONLINE' ORDER BY name ASC";
-                command.CommandTimeout = 15;
-                command.CommandType = CommandType.Text;
-
-                using (var reader = command.ExecuteReader())
-                {
-                    while (reader.Read())
-                    {
-                        results.Add(reader[0].ToString());
-                    }
-                }
-            }
-
-            // Put system databases at the top of the list
-            results =
-                results.Where(s => systemDatabases.Any(s.Equals)).Concat(
-                results.Where(s => systemDatabases.All(x => !s.Equals(x)))).ToList();
-
-            connection.Close();
-
-            ListDatabasesResponse response = new ListDatabasesResponse();
-            response.DatabaseNames = results.ToArray();
-
-            return response;
+            var handler = ListDatabaseRequestHandlerFactory.getHandler(listDatabasesParams.IncludeDetails.HasTrue(), info.IsSqlDb);
+            return handler.HandleRequest(this.connectionFactory, info);
         }
 
         public void InitializeService(IProtocolEndpoint serviceHost)

src/Microsoft.SqlTools.ServiceLayer/Connection/Contracts/ListDatabasesParams.cs

@@ -14,5 +14,10 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection.Contracts
         /// URI of the owner of the connection requesting the list of databases.
         /// </summary>
         public string OwnerUri { get; set; }
+
+        /// <summary>
+        /// whether to include the details of the databases.
+        /// </summary>
+        public bool? IncludeDetails { get; set; }
     }
 }

src/Microsoft.SqlTools.ServiceLayer/Connection/Contracts/ListDatabasesResponse.cs

@@ -3,6 +3,8 @@
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 //
 
+using Microsoft.SqlTools.ServiceLayer.Admin.Contracts;
+
 namespace Microsoft.SqlTools.ServiceLayer.Connection.Contracts
 {
     /// <summary>
@@ -14,5 +16,10 @@ namespace Microsoft.SqlTools.ServiceLayer.Connection.Contracts
         /// Gets or sets the list of database names.
         /// </summary>
         public string[] DatabaseNames { get; set; }
+
+        /// <summary>
+        /// Gets or sets the databases details.
+        /// </summary>
+        public DatabaseInfo[] Databases { get; set; }
     }
 }

src/Microsoft.SqlTools.ServiceLayer/Connection/ListDatabaseRequestHandler.cs

@@ -0,0 +1,226 @@
+//
+// 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;
+using System.Data.Common;
+using System.Linq;
+using Microsoft.SqlTools.ServiceLayer.Admin.Contracts;
+using Microsoft.SqlTools.ServiceLayer.Connection.Contracts;
+
+namespace Microsoft.SqlTools.ServiceLayer.Connection
+{
+    public class ListDatabasesRequestDatabaseProperties
+    {
+        public const string Name = "name";
+        public const string SizeInMB = "sizeInMB";
+        public const string State = "state";
+        public const string LastBackup = "lastBackup";
+    }
+
+    /// <summary>
+    /// Factory class for ListDatabasesRequest handler
+    /// </summary>
+    static class ListDatabaseRequestHandlerFactory
+    {
+        public static IListDatabaseRequestHandler getHandler(bool includeDetails, bool isSqlDB)
+        {
+            if (!includeDetails)
+            {
+                return new DatabaseNamesHandler();
+            }
+            else if (isSqlDB)
+            {
+                return new SqlDBDatabaseDetailHandler();
+            }
+            else
+            {
+                return new SqlServerDatabaseDetailHandler();
+            }
+        }
+    }
+
+    /// <summary>
+    /// Interface of ListDatabasesRequest handler
+    /// </summary>
+    interface IListDatabaseRequestHandler
+    {
+        ListDatabasesResponse HandleRequest(ISqlConnectionFactory connectionFactory, ConnectionInfo connectionInfo);
+    }
+
+    /// <summary>
+    /// Base handler
+    /// </summary>
+    abstract class ListDatabaseRequestHandler<T> : IListDatabaseRequestHandler
+    {
+        private static readonly string[] SystemDatabases = new string[] { "master", "model", "msdb", "tempdb" };
+
+        public abstract string QueryText { get; }
+
+        public ListDatabasesResponse HandleRequest(ISqlConnectionFactory connectionFactory, ConnectionInfo connectionInfo)
+        {
+            ConnectionDetails connectionDetails = connectionInfo.ConnectionDetails.Clone();
+
+            // Connect to master
+            connectionDetails.DatabaseName = "master";
+            using (var connection = connectionFactory.CreateSqlConnection(ConnectionService.BuildConnectionString(connectionDetails), connectionDetails.AzureAccountToken))
+            {
+                connection.Open();
+                ListDatabasesResponse response = new ListDatabasesResponse();
+                using (DbCommand command = connection.CreateCommand())
+                {
+                    command.CommandText = this.QueryText;
+                    command.CommandTimeout = 15;
+                    command.CommandType = CommandType.Text;
+                    using (var reader = command.ExecuteReader())
+                    {
+                        List<T> results = new List<T>();
+                        while (reader.Read())
+                        {
+                            results.Add(this.CreateItem(reader));
+                        }
+                        // Put system databases at the top of the list
+                        results = results.Where(s => SystemDatabases.Any(x => this.NameMatches(x, s))).Concat(
+                            results.Where(s => SystemDatabases.All(x => !this.NameMatches(x, s)))).ToList();
+                        SetResponse(response, results.ToArray());
+                    }
+                }
+                connection.Close();
+                return response;
+            }
+        }
+
+        protected abstract bool NameMatches(string databaseName, T item);
+        protected abstract T CreateItem(DbDataReader reader);
+        protected abstract void SetResponse(ListDatabasesResponse response, T[] results);
+    }
+
+    /// <summary>
+    /// database names handler
+    /// </summary>
+    class DatabaseNamesHandler : ListDatabaseRequestHandler<string>
+    {
+        public override string QueryText
+        {
+            get
+            {
+                return @"SELECT name FROM sys.databases WHERE state_desc='ONLINE' ORDER BY name ASC";
+            }
+        }
+
+        protected override string CreateItem(DbDataReader reader)
+        {
+            return reader[0].ToString();
+        }
+
+        protected override bool NameMatches(string databaseName, string item)
+        {
+            return databaseName == item;
+        }
+
+        protected override void SetResponse(ListDatabasesResponse response, string[] results)
+        {
+            response.DatabaseNames = results;
+        }
+    }
+
+
+    abstract class BaseDatabaseDetailHandler : ListDatabaseRequestHandler<DatabaseInfo>
+    {
+        protected override bool NameMatches(string databaseName, DatabaseInfo item)
+        {
+            return databaseName == item.Options[ListDatabasesRequestDatabaseProperties.Name].ToString();
+        }
+
+        protected override void SetResponse(ListDatabasesResponse response, DatabaseInfo[] results)
+        {
+            response.Databases = results;
+        }
+
+        protected override DatabaseInfo CreateItem(DbDataReader reader)
+        {
+            DatabaseInfo databaseInfo = new DatabaseInfo();
+            SetProperties(reader, databaseInfo);
+            return databaseInfo;
+        }
+
+        protected virtual void SetProperties(DbDataReader reader, DatabaseInfo databaseInfo)
+        {
+            databaseInfo.Options[ListDatabasesRequestDatabaseProperties.Name] = reader["name"].ToString();
+            databaseInfo.Options[ListDatabasesRequestDatabaseProperties.State] = reader["state"].ToString();
+            databaseInfo.Options[ListDatabasesRequestDatabaseProperties.SizeInMB] = reader["size"].ToString();
+        }
+    }
+
+    /// <summary>
+    /// Standalone SQL Server database detail handler
+    /// </summary>
+    class SqlServerDatabaseDetailHandler : BaseDatabaseDetailHandler
+    {
+        public override string QueryText
+        {
+            get
+            {
+                return @"
+WITH
+    db_size
+    AS
+    (
+        SELECT database_id, CAST(SUM(size) * 8.0 / 1024 AS INTEGER) size
+        FROM sys.master_files
+        GROUP BY database_id
+    ),
+    db_backup
+    AS
+    (
+        SELECT database_name, MAX(backup_start_date) AS last_backup
+        FROM msdb..backupset
+        GROUP BY database_name
+    )
+SELECT name, state_desc AS state, db_size.size, db_backup.last_backup
+FROM sys.databases LEFT JOIN db_size ON sys.databases.database_id = db_size.database_id
+LEFT JOIN db_backup ON sys.databases.name = db_backup.database_name
+WHERE state_desc='ONLINE'
+ORDER BY name ASC";
+            }
+        }
+
+        protected override void SetProperties(DbDataReader reader, DatabaseInfo databaseInfo)
+        {
+            base.SetProperties(reader, databaseInfo);
+            databaseInfo.Options[ListDatabasesRequestDatabaseProperties.LastBackup] = reader["last_backup"] == DBNull.Value ? "" : Convert.ToDateTime(reader["last_backup"]).ToString("yyyy-MM-dd hh:mm:ss");
+        }
+    }
+
+    /// <summary>
+    /// SQL DB database detail handler
+    /// </summary>
+    class SqlDBDatabaseDetailHandler : BaseDatabaseDetailHandler
+    {
+        public override string QueryText
+        {
+            get
+            {
+                return @"
+WITH
+    db_size
+    AS
+    (
+        SELECT name, storage_in_megabytes AS size
+        FROM (
+SELECT database_name name, max(end_time) size_time
+            FROM sys.resource_stats
+            GROUP BY database_name) db_size_time
+            LEFT JOIN sys.resource_stats ON database_name = name AND size_time = end_time
+    )
+SELECT db.name, state_desc AS state, size
+FROM sys.databases db LEFT JOIN db_size ON db.name = db_size.name
+WHERE state_desc='ONLINE'
+ORDER BY name ASC
+";
+            }
+        }
+    }
+}