DbDataAdapter async methods #8 - introducing RecordSet.FromReader and…

… RecordSet.FromReaderAsync
nreco · Aug 24, 2016 · 08958af · 08958af
1 parent 11123da
commit 08958af
Show file tree

Hide file tree

Showing 4 changed files with 63 additions and 34 deletions.
diff --git a/src/NReco.Data.Tests/RecordSetTests.cs b/src/NReco.Data.Tests/RecordSetTests.cs
@@ -128,7 +128,7 @@ public void RecordSetReader() {
 			Assert.Equal(100, cnt);
 
 			// read RS from RecordSetReader
-			var testRSCopy = new RecordSet( new RecordSetReader(testRS) );
+			var testRSCopy = RecordSet.FromReader( new RecordSetReader(testRS) );
 			Assert.Equal( testRS.Count, testRSCopy.Count );
 			Assert.Equal( testRS.Columns.Count, testRSCopy.Columns.Count );
 

diff --git a/src/NReco.Data/Internal/DataReaderAsyncExt.cs b/src/NReco.Data/Internal/DataReaderAsyncExt.cs
@@ -32,6 +32,14 @@ internal static Task<bool> ReadAsync(this IDataReader rdr, CancellationToken can
 			}
 		}
 
+		internal static Task<int> GetValuesAsync(this IDataReader rdr, object[] values, CancellationToken cancel) {
+			if (rdr is DbDataReader) {
+				return ((DbDataReader)rdr).GetValuesAsync(values, cancel);
+			} else {
+				return Task.FromResult(rdr.GetValues(values));
+			}
+		}
+
 	}
 
 

diff --git a/src/NReco.Data/RecordSet.cs b/src/NReco.Data/RecordSet.cs
@@ -17,6 +17,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using System.Data;
 
@@ -59,15 +60,6 @@ public int Count {
 		public RecordSet(Column[] columns) : this(columns, 1) {
 		}
 
-		/// <summary>
-		/// Initializes a new instance of <see cref="RecordSet"/> with schema and data from specified <see cref="IDataReader"/>.
-		/// </summary>		 
-		/// <param name="rdr">An <see cref="IDataReader"/> that provides a result set.</param>
-		public RecordSet(IDataReader rdr) {
-			Rows = new List<Row>();
-			LoadInternal(rdr,true);
-		}
-
 		/// <summary>
 		/// Initializes a new instance of <see cref="RecordSet"/> with specified list of <see cref="RecordSet.Column"/> and capacity.
 		/// </summary>
@@ -212,19 +204,10 @@ IEnumerator IEnumerable.GetEnumerator() {
 		/// <param name="rdr">An <see cref="IDataReader"/> that provides a result set.</param>
 		/// <returns>Number of loaded rows.</returns>
 		public int Load(IDataReader rdr) {
-			return LoadInternal(rdr, false);
-		}
-
-		int LoadInternal(IDataReader rdr, bool initColumns) {
 			int processed = 0;
 			while (rdr.Read()) {
 				Tuple<int,int>[] rdrToRsColIdx = null;
-				if (initColumns && columns==null) {
-					var rs = DataHelper.GetRecordSetByReader(rdr);
-					columns = rs.Columns;
-					PrimaryKey = rs.PrimaryKey;
-				}
-				if (!initColumns && rdrToRsColIdx==null) {
+				if (rdrToRsColIdx==null) {
 					var rdrToRsColIdxList = new List<Tuple<int, int>>();
 					for (int i=0; i<rdr.FieldCount; i++) {
 						var colName = rdr.GetName(i);
@@ -235,23 +218,61 @@ int LoadInternal(IDataReader rdr, bool initColumns) {
 				}
 
 				processed++;
-				if (initColumns) {
-					// just copy values
-					var rowValues = new object[rdr.FieldCount];
-					rdr.GetValues(rowValues);
-					this.Add(rowValues).AcceptChanges();
-				} else {
-					var r = this.Add();
-					for (int i=0; i<rdrToRsColIdx.Length; i++) {
-						var t = rdrToRsColIdx[i];
-						r[ t.Item2 ] = rdr.GetValue(t.Item1);
-					}
-					r.AcceptChanges();
+
+				var r = this.Add();
+				for (int i=0; i<rdrToRsColIdx.Length; i++) {
+					var t = rdrToRsColIdx[i];
+					r[ t.Item2 ] = rdr.GetValue(t.Item1);
 				}
+				r.AcceptChanges();
+
 			}
 			return processed;
 		}
 
+		/// <summary>
+		/// Creates a <see cref="RecordSet"/> from a data source using the supplied <see cref="IDataReader"/>.
+		/// </summary>
+		/// <param name="rdr">An <see cref="IDataReader"/> that provides a result set.</param>
+		/// <returns><see cref="RecordSet"/> with schema inferred by reader and populated with incoming data.</returns>
+		public static RecordSet FromReader(IDataReader rdr) {
+			RecordSet rs = null;
+			while (rdr.Read()) {
+				if (rs==null) {
+					rs = DataHelper.GetRecordSetByReader(rdr);
+				}
+				// just copy values
+				var rowValues = new object[rdr.FieldCount];
+				rdr.GetValues(rowValues);
+				rs.Add(rowValues).AcceptChanges();
+			}
+			return rs;
+		}
+
+		/// <summary>
+		/// Asynchronously creates a <see cref="RecordSet"/> from a data source using the supplied <see cref="IDataReader"/>.
+		/// </summary>
+		public static Task<RecordSet> FromReaderAsync(IDataReader rdr) {
+			return FromReaderAsync(rdr, CancellationToken.None);
+		}
+
+		/// <summary>
+		/// Asynchronously creates a <see cref="RecordSet"/> from a data source using the supplied <see cref="IDataReader"/>.
+		/// </summary>
+		public static async Task<RecordSet> FromReaderAsync(IDataReader rdr, CancellationToken cancel) {
+			RecordSet rs = null;
+			while (await rdr.ReadAsync(cancel).ConfigureAwait(false)) {
+				if (rs==null) {
+					rs = DataHelper.GetRecordSetByReader(rdr);
+				}
+				// just copy values
+				var rowValues = new object[rdr.FieldCount];
+				await rdr.GetValuesAsync(rowValues, cancel).ConfigureAwait(false);
+				rs.Add(rowValues).AcceptChanges();
+			}
+			return rs;
+		}
+
 		/// <summary>
 		/// Represents the schema of a column in a <see cref="RecordSet"/>.
 		/// </summary>

diff --git a/src/NReco.Data/project.json b/src/NReco.Data/project.json
@@ -1,13 +1,13 @@
 {
-  "version": "1.0.0-alpha4",
+  "version": "1.0.0-alpha5",
   "title": "NReco.Data",
   "description": "Lightweight db-independent DAL for generating SQL commands by abstract queries, schema-less CRUD operations, POCO mapping.",
   "authors": [ "Vitalii Fedorchenko" ],
   "copyright": "Copyright (c) 2016 Vitalii Fedorchenko",
   "packOptions": {
     "owners": [ "Vitalii Fedorchenko" ],
     "projectUrl": "http://www.nrecosite.com/dalc_net.aspx",
-    "tags": [ "DAL", "ado.net", "data", "relex", "sql", "query", "recordset", "generator", "batch", "database", "micro-orm", "data-mapper", "poco", "schema-less", "netstandard", "netcore", "net40", "net45" ],
+    "tags": [ "DAL", "ado.net", "data", "relex", "sql", "query", "recordset", "generator", "batch", "database", "micro-orm", "data-mapper", "poco", "schema-less", "netstandard", "netcore", "net45" ],
     "licenseUrl": "https://raw.githubusercontent.com/nreco/data/master/LICENSE",
     "iconUrl": "http://www.nrecosite.com/img/nreco-logo-200.png"
   },