Add typed procedure contract result handling

AmalgamationTool/DynamORM.Amalgamation.cs

@@ -5358,7 +5358,8 @@ namespace DynamORM
             CallInfo info = binder.CallInfo;
 
             // Get generic types
-            IList<Type> types = binder.GetGenericTypeArguments();
+            IList<Type> types = binder.GetGenericTypeArguments() ?? new List<Type>();
+            Type declaredResultType = null;
 
             Dictionary<string, int> retParams = null;
 
@@ -5374,6 +5375,7 @@ namespace DynamORM
 
                 int alen = args.Length;
                 bool retIsAdded = false;
+                declaredResultType = alen == 1 ? DynamicProcedureResultBinder.GetDeclaredResultType(args[0]) : null;
 
                 if (alen > 0)
                 {
@@ -5539,7 +5541,13 @@ namespace DynamORM
 
                 object mainResult = null;
 
-                if (types.Count > 0)
+                if (types.Count == 0 && DynamicProcedureResultBinder.CanReadResults(declaredResultType))
+                {
+                    using (IDataReader rdr = cmd.ExecuteReader())
+                    using (IDataReader cache = rdr.CachedReader())
+                        mainResult = DynamicProcedureResultBinder.ReadDeclaredResult(declaredResultType, cache);
+                }
+                else if (types.Count > 0)
                 {
                     mainResult = types[0].GetDefaultValue();
 
@@ -5695,9 +5703,15 @@ namespace DynamORM
                         else
                             result = res.ToDynamic();
                     }
+                    else if (declaredResultType != null)
+                        result = DynamicProcedureResultBinder.BindPayload(declaredResultType, binder.Name, mainResult, res.Where(x => x.Key != binder.Name).ToDictionary(x => x.Key, x => x.Value), mainResult != null && declaredResultType.IsInstanceOfType(mainResult) ? mainResult : null);
                     else
                         result = res.ToDynamic();
                 }
+                else if (declaredResultType != null && mainResult != null && declaredResultType.IsInstanceOfType(mainResult))
+                    result = mainResult;
+                else if (declaredResultType != null)
+                    result = DynamicProcedureResultBinder.BindPayload(declaredResultType, binder.Name, mainResult, null);
                 else
                     result = mainResult;
 
@@ -6835,6 +6849,22 @@ namespace DynamORM
 
         #endregion IExtendedDisposable Members
     }
+    /// <summary>Marks an object as an explicit stored procedure parameter contract.</summary>
+    public interface IProcedureParameters
+    {
+    }
+    /// <summary>Marks an object as a stored procedure parameter contract with a declared typed result model.</summary>
+    /// <typeparam name="TResult">Typed result model.</typeparam>
+    public interface IProcedureParameters<TResult> : IProcedureParameters
+    {
+    }
+    /// <summary>Allows typed procedure result models to consume multiple result sets directly.</summary>
+    public interface IProcedureResultReader
+    {
+        /// <summary>Reads all required result sets from the procedure reader.</summary>
+        /// <param name="reader">Procedure result reader, usually a cached reader.</param>
+        void ReadResults(IDataReader reader);
+    }
     /// <summary>Declares metadata for object-based stored procedure parameters.</summary>
     [AttributeUsage(AttributeTargets.Property)]
     public class ProcedureParameterAttribute : ColumnAttribute
@@ -14482,15 +14512,10 @@ namespace DynamORM
                 }
                 internal static bool CanBind(object item)
                 {
-                    if (item == null)
+                    if (!DynamicProcedureResultBinder.IsProcedureContract(item))
                         return false;
 
-                    Type type = item.GetType();
+                    return GetBindableProperties(item.GetType()).Any();
-
-                    if (type.IsPrimitive || type.IsEnum || type == typeof(string) || type == typeof(decimal) || type == typeof(DateTime) || type == typeof(Guid) || type == typeof(TimeSpan))
-                        return false;
-
-                    return GetBindableProperties(type).Any();
                 }
                 internal static BindingResult Bind(DynamicDatabase db, IDbCommand cmd, object item)
                 {
@@ -14600,6 +14625,70 @@ namespace DynamORM
                     return 0;
                 }
             }
+            internal static class DynamicProcedureResultBinder
+            {
+                internal static bool IsProcedureContract(object item)
+                {
+                    return item is IProcedureParameters;
+                }
+                internal static Type GetDeclaredResultType(object item)
+                {
+                    if (item == null)
+                        return null;
+
+                    Type iface = item.GetType().GetInterfaces()
+                        .FirstOrDefault(x => x.IsGenericType && x.GetGenericTypeDefinition() == typeof(IProcedureParameters<>));
+
+                    return iface == null ? null : iface.GetGenericArguments()[0];
+                }
+                internal static bool CanReadResults(Type resultType)
+                {
+                    return resultType != null && typeof(IProcedureResultReader).IsAssignableFrom(resultType);
+                }
+                internal static object CreateDeclaredResult(Type resultType)
+                {
+                    if (resultType == null)
+                        return null;
+
+                    DynamicTypeMap mapper = DynamicMapperCache.GetMapper(resultType);
+                    if (mapper != null)
+                        return mapper.Creator();
+
+                    return Activator.CreateInstance(resultType);
+                }
+                internal static object ReadDeclaredResult(Type resultType, IDataReader reader)
+                {
+                    if (!CanReadResults(resultType))
+                        throw new InvalidOperationException(string.Format("Type '{0}' does not implement IProcedureResultReader.", resultType == null ? "<null>" : resultType.FullName));
+
+                    object instance = CreateDeclaredResult(resultType);
+                    ((IProcedureResultReader)instance).ReadResults(reader);
+                    return instance;
+                }
+                internal static object BindPayload(Type resultType, string mainResultName, object mainResult, IDictionary<string, object> returnValues, object existing = null)
+                {
+                    if (resultType == null)
+                        return existing ?? returnValues.ToDynamic();
+
+                    Dictionary<string, object> payload = new Dictionary<string, object>();
+
+                    if (mainResultName != null)
+                        payload[mainResultName] = mainResult == DBNull.Value ? null : mainResult;
+
+                    if (returnValues != null)
+                        foreach (KeyValuePair<string, object> item in returnValues)
+                            payload[item.Key] = item.Value == DBNull.Value ? null : item.Value;
+
+                    DynamicTypeMap mapper = DynamicMapperCache.GetMapper(resultType);
+                    if (mapper != null)
+                        return mapper.Map(payload.ToDynamic(), existing ?? mapper.Creator());
+
+                    if (existing != null)
+                        return existing;
+
+                    return payload.ToDynamic();
+                }
+            }
             /// <summary>Framework detection and specific implementations.</summary>
             public static class FrameworkTools
             {

DynamORM.Tests/Helpers/FakeMultiResultDataReader.cs

@@ -0,0 +1,135 @@
+/*
+ * DynamORM - Dynamic Object-Relational Mapping library.
+ * Copyright (c) 2012-2026, Grzegorz Russek (grzegorz.russek@gmail.com)
+ * All rights reserved.
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Data;
+
+namespace DynamORM.Tests.Helpers
+{
+    internal sealed class FakeMultiResultDataReader : IDataReader
+    {
+        private sealed class ResultSet
+        {
+            public string[] Names;
+            public Type[] Types;
+            public object[][] Rows;
+        }
+
+        private readonly List<ResultSet> _sets = new List<ResultSet>();
+        private int _setIndex;
+        private int _rowIndex = -1;
+
+        public FakeMultiResultDataReader(params Tuple<string[], Type[], object[][]>[] sets)
+        {
+            foreach (var set in sets)
+                _sets.Add(new ResultSet
+                {
+                    Names = set.Item1,
+                    Types = set.Item2,
+                    Rows = set.Item3
+                });
+        }
+
+        private ResultSet Current { get { return _sets[_setIndex]; } }
+
+        public object this[string name] { get { return GetValue(GetOrdinal(name)); } }
+        public object this[int i] { get { return GetValue(i); } }
+        public int Depth { get { return 0; } }
+        public bool IsClosed { get; private set; }
+        public int RecordsAffected { get { return 0; } }
+        public int FieldCount { get { return Current.Names.Length; } }
+
+        public void Close() { IsClosed = true; }
+        public void Dispose() { Close(); }
+        public bool GetBoolean(int i) { return (bool)GetValue(i); }
+        public byte GetByte(int i) { return (byte)GetValue(i); }
+        public long GetBytes(int i, long fieldOffset, byte[] buffer, int bufferoffset, int length) { throw new NotSupportedException(); }
+        public char GetChar(int i) { return (char)GetValue(i); }
+        public long GetChars(int i, long fieldoffset, char[] buffer, int bufferoffset, int length) { throw new NotSupportedException(); }
+        public IDataReader GetData(int i) { throw new NotSupportedException(); }
+        public string GetDataTypeName(int i) { return GetFieldType(i).Name; }
+        public DateTime GetDateTime(int i) { return (DateTime)GetValue(i); }
+        public decimal GetDecimal(int i) { return (decimal)GetValue(i); }
+        public double GetDouble(int i) { return (double)GetValue(i); }
+        public Type GetFieldType(int i) { return Current.Types[i]; }
+        public float GetFloat(int i) { return (float)GetValue(i); }
+        public Guid GetGuid(int i) { return (Guid)GetValue(i); }
+        public short GetInt16(int i) { return Convert.ToInt16(GetValue(i)); }
+        public int GetInt32(int i) { return Convert.ToInt32(GetValue(i)); }
+        public long GetInt64(int i) { return Convert.ToInt64(GetValue(i)); }
+        public string GetName(int i) { return Current.Names[i]; }
+        public int GetOrdinal(string name)
+        {
+            for (int i = 0; i < Current.Names.Length; i++)
+                if (string.Equals(Current.Names[i], name, StringComparison.OrdinalIgnoreCase))
+                    return i;
+            return -1;
+        }
+        public DataTable GetSchemaTable()
+        {
+            DataTable schema = new DataTable();
+            schema.Columns.Add("ColumnName", typeof(string));
+            schema.Columns.Add("ColumnOrdinal", typeof(int));
+            schema.Columns.Add("ColumnSize", typeof(int));
+            schema.Columns.Add("NumericPrecision", typeof(short));
+            schema.Columns.Add("NumericScale", typeof(short));
+            schema.Columns.Add("DataType", typeof(Type));
+            schema.Columns.Add("ProviderType", typeof(int));
+            schema.Columns.Add("NativeType", typeof(int));
+            schema.Columns.Add("AllowDBNull", typeof(bool));
+            schema.Columns.Add("IsUnique", typeof(bool));
+            schema.Columns.Add("IsKey", typeof(bool));
+            schema.Columns.Add("IsAutoIncrement", typeof(bool));
+
+            for (int i = 0; i < Current.Names.Length; i++)
+            {
+                DataRow row = schema.NewRow();
+                row[0] = Current.Names[i];
+                row[1] = i;
+                row[2] = 0;
+                row[3] = 0;
+                row[4] = 0;
+                row[5] = Current.Types[i];
+                row[6] = 0;
+                row[7] = 0;
+                row[8] = true;
+                row[9] = false;
+                row[10] = false;
+                row[11] = false;
+                schema.Rows.Add(row);
+            }
+
+            return schema;
+        }
+        public string GetString(int i) { return (string)GetValue(i); }
+        public object GetValue(int i) { return Current.Rows[_rowIndex][i]; }
+        public int GetValues(object[] values)
+        {
+            int count = Math.Min(values.Length, FieldCount);
+            for (int i = 0; i < count; i++)
+                values[i] = GetValue(i);
+            return count;
+        }
+        public bool IsDBNull(int i) { return GetValue(i) == null || GetValue(i) == DBNull.Value; }
+        public bool NextResult()
+        {
+            if (_setIndex + 1 >= _sets.Count)
+                return false;
+
+            _setIndex++;
+            _rowIndex = -1;
+            return true;
+        }
+        public bool Read()
+        {
+            if (_rowIndex + 1 >= Current.Rows.Length)
+                return false;
+            _rowIndex++;
+            return true;
+        }
+    }
+}

DynamORM.Tests/Helpers/ProcedureParameterModels.cs

@@ -8,7 +8,7 @@ using System.Data;
 
 namespace DynamORM.Tests.Helpers
 {
-    public class ProcedureParameterObject
+    public class ProcedureParameterObject : IProcedureParameters<ProcedureParameterResult>
     {
         [ProcedureParameter("code", Order = 2, DbType = DbType.String, Size = 32)]
         public string Code { get; set; }
@@ -23,9 +23,52 @@ namespace DynamORM.Tests.Helpers
         public int Status { get; set; }
     }
 
-    public class ProcedureParameterColumnFallbackObject
+    public class ProcedureParameterColumnFallbackObject : IProcedureParameters
     {
         [DynamORM.Mapper.Column("code", false, DbType.String, 64)]
         public string Code { get; set; }
     }
+
+    public class ProcedureParameterResult
+    {
+        [DynamORM.Mapper.Column("sp_Test")]
+        public int MainResult { get; set; }
+
+        [DynamORM.Mapper.Column("result")]
+        public int Result { get; set; }
+
+        [DynamORM.Mapper.Column("description")]
+        public string Description { get; set; }
+
+        [DynamORM.Mapper.Column("status")]
+        public int Status { get; set; }
+    }
+
+    public class ProcedureMultiResult : IProcedureResultReader
+    {
+        [DynamORM.Mapper.Column("sp_Multi")]
+        public int MainResult { get; set; }
+
+        [DynamORM.Mapper.Column("status")]
+        public int Status { get; set; }
+
+        public System.Collections.Generic.List<string> Codes { get; private set; } = new System.Collections.Generic.List<string>();
+        public System.Collections.Generic.List<int> States { get; private set; } = new System.Collections.Generic.List<int>();
+
+        public void ReadResults(IDataReader reader)
+        {
+            while (reader.Read())
+                Codes.Add(reader.GetString(0));
+
+            if (reader.NextResult())
+                while (reader.Read())
+                    States.Add(reader.GetInt32(0));
+        }
+    }
+
+    public class ProcedureMultiResultArgs : IProcedureParameters<ProcedureMultiResult>
+    {
+        [ProcedureParameter("status", Direction = ParameterDirection.Output, Order = 1, DbType = DbType.Int32)]
+        public int Status { get; set; }
+    }
 }

DynamORM.Tests/Procedure/ProcedureParameterBinderTests.cs

@@ -113,5 +113,87 @@ namespace DynamORM.Tests.Procedure
                 Assert.AreEqual("XYZ", p0.Value);
             }
         }
+
+        [Test]
+        public void TestDeclaredResultTypeComesFromContractInterface()
+        {
+            Assert.AreEqual(typeof(ProcedureParameterResult), DynamicProcedureResultBinder.GetDeclaredResultType(new ProcedureParameterObject()));
+            Assert.AreEqual(typeof(ProcedureMultiResult), DynamicProcedureResultBinder.GetDeclaredResultType(new ProcedureMultiResultArgs()));
+            Assert.IsNull(DynamicProcedureResultBinder.GetDeclaredResultType(new object()));
+        }
+
+        [Test]
+        public void TestDeclaredResultPayloadBindingMapsMainAndOutValues()
+        {
+            var result = DynamicProcedureResultBinder.BindPayload(
+                typeof(ProcedureParameterResult),
+                "sp_Test",
+                15,
+                new System.Collections.Generic.Dictionary<string, object>
+                {
+                    { "result", 7 },
+                    { "description", "done" },
+                    { "status", 3 }
+                }) as ProcedureParameterResult;
+
+            Assert.NotNull(result);
+            Assert.AreEqual(15, result.MainResult);
+            Assert.AreEqual(7, result.Result);
+            Assert.AreEqual("done", result.Description);
+            Assert.AreEqual(3, result.Status);
+        }
+
+        [Test]
+        public void TestDeclaredResultReaderCanConsumeMultipleResultSets()
+        {
+            using (var reader = new FakeMultiResultDataReader(
+                Tuple.Create(
+                    new[] { "Code" },
+                    new[] { typeof(string) },
+                    new[]
+                    {
+                        new object[] { "A" },
+                        new object[] { "B" }
+                    }),
+                Tuple.Create(
+                    new[] { "State" },
+                    new[] { typeof(int) },
+                    new[]
+                    {
+                        new object[] { 10 },
+                        new object[] { 20 }
+                    })))
+            {
+                var result = DynamicProcedureResultBinder.ReadDeclaredResult(typeof(ProcedureMultiResult), reader) as ProcedureMultiResult;
+
+                Assert.NotNull(result);
+                CollectionAssert.AreEqual(new[] { "A", "B" }, result.Codes);
+                CollectionAssert.AreEqual(new[] { 10, 20 }, result.States);
+            }
+        }
+
+        [Test]
+        public void TestDeclaredResultPayloadCanAugmentReaderResult()
+        {
+            var existing = new ProcedureMultiResult();
+            existing.Codes.Add("A");
+            existing.States.Add(10);
+
+            var result = DynamicProcedureResultBinder.BindPayload(
+                typeof(ProcedureMultiResult),
+                "sp_Multi",
+                99,
+                new System.Collections.Generic.Dictionary<string, object>
+                {
+                    { "status", 5 }
+                },
+                existing) as ProcedureMultiResult;
+
+            Assert.AreSame(existing, result);
+            Assert.AreEqual(99, result.MainResult);
+            Assert.AreEqual(5, result.Status);
+            CollectionAssert.AreEqual(new[] { "A" }, result.Codes);
+            CollectionAssert.AreEqual(new[] { 10 }, result.States);
+        }
     }
 }

DynamORM/DynamicProcedureInvoker.cs

@@ -92,7 +92,8 @@ namespace DynamORM
             CallInfo info = binder.CallInfo;
 
             // Get generic types
-            IList<Type> types = binder.GetGenericTypeArguments();
+            IList<Type> types = binder.GetGenericTypeArguments() ?? new List<Type>();
+            Type declaredResultType = null;
 
             Dictionary<string, int> retParams = null;
 
@@ -108,6 +109,7 @@ namespace DynamORM
 
                 int alen = args.Length;
                 bool retIsAdded = false;
+                declaredResultType = alen == 1 ? DynamicProcedureResultBinder.GetDeclaredResultType(args[0]) : null;
 
                 if (alen > 0)
                 {
@@ -280,7 +282,13 @@ namespace DynamORM
 
                 object mainResult = null;
 
-                if (types.Count > 0)
+                if (types.Count == 0 && DynamicProcedureResultBinder.CanReadResults(declaredResultType))
+                {
+                    using (IDataReader rdr = cmd.ExecuteReader())
+                    using (IDataReader cache = rdr.CachedReader())
+                        mainResult = DynamicProcedureResultBinder.ReadDeclaredResult(declaredResultType, cache);
+                }
+                else if (types.Count > 0)
                 {
                     mainResult = types[0].GetDefaultValue();
 
@@ -442,9 +450,15 @@ namespace DynamORM
                         else
                             result = res.ToDynamic();
                     }
+                    else if (declaredResultType != null)
+                        result = DynamicProcedureResultBinder.BindPayload(declaredResultType, binder.Name, mainResult, res.Where(x => x.Key != binder.Name).ToDictionary(x => x.Key, x => x.Value), mainResult != null && declaredResultType.IsInstanceOfType(mainResult) ? mainResult : null);
                     else
                         result = res.ToDynamic();
                 }
+                else if (declaredResultType != null && mainResult != null && declaredResultType.IsInstanceOfType(mainResult))
+                    result = mainResult;
+                else if (declaredResultType != null)
+                    result = DynamicProcedureResultBinder.BindPayload(declaredResultType, binder.Name, mainResult, null);
                 else
                     result = mainResult;
 

DynamORM/Helpers/DynamicProcedureParameterBinder.cs

@@ -45,15 +45,10 @@ namespace DynamORM.Helpers
 
         internal static bool CanBind(object item)
         {
-            if (item == null)
+            if (!DynamicProcedureResultBinder.IsProcedureContract(item))
                 return false;
 
-            Type type = item.GetType();
+            return GetBindableProperties(item.GetType()).Any();
-
-            if (type.IsPrimitive || type.IsEnum || type == typeof(string) || type == typeof(decimal) || type == typeof(DateTime) || type == typeof(Guid) || type == typeof(TimeSpan))
-                return false;
-
-            return GetBindableProperties(type).Any();
         }
 
         internal static BindingResult Bind(DynamicDatabase db, IDbCommand cmd, object item)

DynamORM/Helpers/DynamicProcedureResultBinder.cs

@@ -0,0 +1,106 @@
+/*
+ * DynamORM - Dynamic Object-Relational Mapping library.
+ * Copyright (c) 2012-2026, Grzegorz Russek (grzegorz.russek@gmail.com)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+using System;
+using System.Collections.Generic;
+using System.Data;
+using System.Linq;
+using DynamORM.Mapper;
+
+namespace DynamORM.Helpers
+{
+    internal static class DynamicProcedureResultBinder
+    {
+        internal static bool IsProcedureContract(object item)
+        {
+            return item is IProcedureParameters;
+        }
+
+        internal static Type GetDeclaredResultType(object item)
+        {
+            if (item == null)
+                return null;
+
+            Type iface = item.GetType().GetInterfaces()
+                .FirstOrDefault(x => x.IsGenericType && x.GetGenericTypeDefinition() == typeof(IProcedureParameters<>));
+
+            return iface == null ? null : iface.GetGenericArguments()[0];
+        }
+
+        internal static bool CanReadResults(Type resultType)
+        {
+            return resultType != null && typeof(IProcedureResultReader).IsAssignableFrom(resultType);
+        }
+
+        internal static object CreateDeclaredResult(Type resultType)
+        {
+            if (resultType == null)
+                return null;
+
+            DynamicTypeMap mapper = DynamicMapperCache.GetMapper(resultType);
+            if (mapper != null)
+                return mapper.Creator();
+
+            return Activator.CreateInstance(resultType);
+        }
+
+        internal static object ReadDeclaredResult(Type resultType, IDataReader reader)
+        {
+            if (!CanReadResults(resultType))
+                throw new InvalidOperationException(string.Format("Type '{0}' does not implement IProcedureResultReader.", resultType == null ? "<null>" : resultType.FullName));
+
+            object instance = CreateDeclaredResult(resultType);
+            ((IProcedureResultReader)instance).ReadResults(reader);
+            return instance;
+        }
+
+        internal static object BindPayload(Type resultType, string mainResultName, object mainResult, IDictionary<string, object> returnValues, object existing = null)
+        {
+            if (resultType == null)
+                return existing ?? returnValues.ToDynamic();
+
+            Dictionary<string, object> payload = new Dictionary<string, object>();
+
+            if (mainResultName != null)
+                payload[mainResultName] = mainResult == DBNull.Value ? null : mainResult;
+
+            if (returnValues != null)
+                foreach (KeyValuePair<string, object> item in returnValues)
+                    payload[item.Key] = item.Value == DBNull.Value ? null : item.Value;
+
+            DynamicTypeMap mapper = DynamicMapperCache.GetMapper(resultType);
+            if (mapper != null)
+                return mapper.Map(payload.ToDynamic(), existing ?? mapper.Creator());
+
+            if (existing != null)
+                return existing;
+
+            return payload.ToDynamic();
+        }
+    }
+}

DynamORM/ProcedureContracts.cs

@@ -0,0 +1,51 @@
+/*
+ * DynamORM - Dynamic Object-Relational Mapping library.
+ * Copyright (c) 2012-2026, Grzegorz Russek (grzegorz.russek@gmail.com)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+using System.Data;
+
+namespace DynamORM
+{
+    /// <summary>Marks an object as an explicit stored procedure parameter contract.</summary>
+    public interface IProcedureParameters
+    {
+    }
+
+    /// <summary>Marks an object as a stored procedure parameter contract with a declared typed result model.</summary>
+    /// <typeparam name="TResult">Typed result model.</typeparam>
+    public interface IProcedureParameters<TResult> : IProcedureParameters
+    {
+    }
+
+    /// <summary>Allows typed procedure result models to consume multiple result sets directly.</summary>
+    public interface IProcedureResultReader
+    {
+        /// <summary>Reads all required result sets from the procedure reader.</summary>
+        /// <param name="reader">Procedure result reader, usually a cached reader.</param>
+        void ReadResults(IDataReader reader);
+    }
+}