API 2.0 skeleton (dotnet#149)

Incorporating API review feedback

Author: vinodshanbhag

src/Microsoft.ML.Auto/APINew/MLContextExtension.cs

@@ -0,0 +1,122 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using Microsoft.Data.DataView;
+using Microsoft.ML.Core.Data;
+using Microsoft.ML.Data;
+
+namespace Microsoft.ML.Auto.APINew
+{
+    public static class MLContextExtension
+    {
+        public static AutoInfereceCataglog AutoInference(this MLContext mlContext)
+        {
+            return new AutoInfereceCataglog();
+        }
+    }
+
+    public class ExperimentSettings
+    {
+        public uint MaxInferenceTimeInSeconds;
+        public bool EnableCaching;
+        public CancellationToken CancellationToken;
+    }
+
+    public class RegressionExperimentSettings : ExperimentSettings
+    {
+        public IProgress<Data.RegressionMetrics> ProgressCallback;
+        public Data.RegressionMetrics OptimizingMetrics;
+        public RegressionTrainer[] WhitelistedTrainers;
+    }
+
+    public enum RegressionMetric
+    {
+        RSquared
+    }
+
+    public enum RegressionTrainer
+    {
+        LightGbm
+    }
+
+    public class ColumnInfereceResults
+    {
+        public TextLoader.Arguments TextLoaderArgs;
+        public ColumnInformation ColumnInformation;
+    }
+
+    public class ColumnInformation
+    {
+        public string LableColumn;
+        public string WeightColumn;
+        public IEnumerable<string> CategoricalColumns;
+    }
+
+    public class RegressionExperiment
+    {
+        public RunResult<RegressionMetric> Execute(IDataView testData, ColumnInformation columnInformation = null, IEstimator<ITransformer> preFeaturizers = null)
+        {
+            throw new NotImplementedException();
+        }
+
+        public RunResult<RegressionMetric> Execute(IDataView testData, IDataView validationData, ColumnInformation columnInformation = null, IEstimator<ITransformer> preFeaturizers = null)
+        {
+            throw new NotImplementedException();
+        }
+
+        public RunResult<RegressionMetric> Execute(IDataView testData, uint numberOfCVFolds, ColumnInformation columnInformation = null, IEstimator<ITransformer> preFeaturizers = null)
+        {
+            throw new NotImplementedException();
+        }
+    }
+
+    public class AutoInfereceCataglog
+    {
+        RegressionExperiment CreateRegressionExperiment(uint maxInferenceTimeInSeconds)
+        {
+            return new RegressionExperiment();
+        }
+
+        RegressionExperiment CreateRegressionExperiment(RegressionExperimentSettings experimentSettings)
+        {
+            return new RegressionExperiment();
+        }
+
+        public ColumnInfereceResults InferColumns()
+        {
+            throw new NotImplementedException();
+        }
+    }
+
+    public class RunResult<T>
+    {
+        public readonly T Metrics;
+        public readonly ITransformer Model;
+        public readonly Exception Exception;
+        public readonly string TrainerName;
+        public readonly int RuntimeInSeconds;
+
+        internal readonly Pipeline Pipeline;
+        internal readonly int PipelineInferenceTimeInSeconds;
+
+        internal RunResult(
+            ITransformer model,
+            T metrics,
+            Pipeline pipeline,
+            Exception exception,
+            int runtimeInSeconds,
+            int pipelineInferenceTimeInSeconds)
+        {
+            Model = model;
+            Metrics = metrics;
+            Pipeline = pipeline;
+            Exception = exception;
+            RuntimeInSeconds = runtimeInSeconds;
+            PipelineInferenceTimeInSeconds = pipelineInferenceTimeInSeconds;
+
+            TrainerName = pipeline?.Nodes.Where(n => n.NodeType == PipelineNodeType.Trainer).Last().Name;
+        }
+    }
+}