ColumnBindingsBase and ISchema are now internal. Schema and ColumnBindingsBase no longer

implement ISchema.

Author: Pete Luferenko

src/Microsoft.ML.Core/Data/IDataView.cs

@@ -12,7 +12,8 @@ namespace Microsoft.ML.Runtime.Data
     /// Legacy interface for schema information.
     /// Please avoid implementing this interface, use <see cref="Schema"/>.
     /// </summary>
-    public interface ISchema
+    [BestFriend]
+    internal interface ISchema
     {
         /// <summary>
         /// Number of columns.

src/Microsoft.ML.Core/Data/Schema.cs

@@ -22,7 +22,7 @@ namespace Microsoft.ML.Data
     /// and values.
     /// </summary>
     [System.Diagnostics.DebuggerTypeProxy(typeof(SchemaDebuggerProxy))]
-    public sealed class Schema : ISchema, IReadOnlyList<Schema.Column>
+    public sealed class Schema : IReadOnlyList<Schema.Column>
     {
         private readonly Column[] _columns;
         private readonly Dictionary<string, int> _nameMap;
@@ -273,9 +273,6 @@ internal static Schema Create(ISchema inputSchema)
         {
             Contracts.CheckValue(inputSchema, nameof(inputSchema));
 
-            if (inputSchema is Schema s)
-                return s;
-
             var builder = new SchemaBuilder();
             for (int i = 0; i < inputSchema.ColumnCount; i++)
             {
@@ -310,31 +307,5 @@ internal bool TryGetColumnIndex(string name, out int col)
             col = GetColumnOrNull(name)?.Index ?? -1;
             return col >= 0;
         }
-
-        #region Legacy schema API to be removed
-        /// <summary>
-        /// Number of columns in the schema.
-        /// </summary>
-        int ISchema.ColumnCount => _columns.Length;
-
-        string ISchema.GetColumnName(int col) => this[col].Name;
-
-        ColumnType ISchema.GetColumnType(int col) => this[col].Type;
-
-        IEnumerable<KeyValuePair<string, ColumnType>> ISchema.GetMetadataTypes(int col)
-            => this[col].Metadata.Schema.Select(c => new KeyValuePair<string, ColumnType>(c.Name, c.Type));
-
-        ColumnType ISchema.GetMetadataTypeOrNull(string kind, int col)
-            => this[col].Metadata.Schema.GetColumnOrNull(kind)?.Type;
-
-        void ISchema.GetMetadata<TValue>(string kind, int col, ref TValue value)
-            => this[col].Metadata.GetValue(kind, ref value);
-
-        bool ISchema.TryGetColumnIndex(string name, out int col)
-        {
-            col = GetColumnOrNull(name)?.Index ?? -1;
-            return col >= 0;
-        }
-        #endregion
     }
 }

src/Microsoft.ML.Data/Data/ITransposeDataView.cs

@@ -25,7 +25,8 @@ namespace Microsoft.ML.Runtime.Data
     /// is accessible in this fashion iff <see cref="TransposeSchema"/>'s
     /// <see cref="ITransposeSchema.GetSlotType"/> returns a non-null value.
     /// </summary>
-    public interface ITransposeDataView : IDataView
+    [BestFriend]
+    internal interface ITransposeDataView : IDataView
     {
         /// <summary>
         /// An enhanced schema, containing information on the transposition properties, if any,
@@ -44,7 +45,8 @@ public interface ITransposeDataView : IDataView
     /// <summary>
     /// The transpose schema returns the schema information of the view we have transposed.
     /// </summary>
-    public interface ITransposeSchema : ISchema
+    [BestFriend]
+    internal interface ITransposeSchema : ISchema
     {
         /// <summary>
         /// Analogous to <see cref="ISchema.GetColumnType"/>, except instead of returning the type of value

src/Microsoft.ML.Data/DataLoadSave/CompositeDataLoader.cs

@@ -409,7 +409,7 @@ private CompositeDataLoader(IHost host, TransformEx[] transforms)
 
             View = transforms[transforms.Length - 1].Transform;
             _tview = View as ITransposeDataView;
-            TransposeSchema = _tview?.TransposeSchema ?? new TransposerUtils.SimpleTransposeSchema(View.Schema);
+            _transposeSchema = _tview?.TransposeSchema ?? new TransposerUtils.SimpleTransposeSchema(View.Schema);
 
             var srcLoader = transforms[0].Transform.Source as IDataLoader;
 
@@ -566,7 +566,8 @@ private static string GenerateTag(int index)
 
         public Schema Schema => View.Schema;
 
-        public ITransposeSchema TransposeSchema { get; }
+        private readonly ITransposeSchema _transposeSchema;
+        ITransposeSchema ITransposeDataView.TransposeSchema => _transposeSchema;
 
         public RowCursor GetRowCursor(Func<int, bool> predicate, Random rand = null)
         {
@@ -586,7 +587,7 @@ public RowCursor[] GetRowCursorSet(out IRowCursorConsolidator consolidator,
         public SlotCursor GetSlotCursor(int col)
         {
             _host.CheckParam(0 <= col && col < Schema.Count, nameof(col));
-            if (TransposeSchema?.GetSlotType(col) == null)
+            if (_transposeSchema?.GetSlotType(col) == null)
             {
                 throw _host.ExceptParam(nameof(col), "Bad call to GetSlotCursor on untransposable column '{0}'",
                     Schema[col].Name);

src/Microsoft.ML.Data/DataLoadSave/Transpose/TransposeLoader.cs

@@ -367,7 +367,7 @@ private static VersionInfo GetVersionInfo()
         // to use the cursors from the schema view if convenient to do so.
         public Schema Schema { get { return _schemaEntry.GetView().Schema; } }
 
-        public ITransposeSchema TransposeSchema { get { return _schema; } }
+        ITransposeSchema ITransposeDataView.TransposeSchema { get { return _schema; } }
 
         /// <summary>
         /// Whether the master schema sub-IDV has the actual data.
@@ -698,7 +698,7 @@ public SlotCursor GetSlotCursor(int col)
             _host.CheckParam(0 <= col && col < _header.ColumnCount, nameof(col));
             // We don't want the type error, if there is one, to be handled by the get-getter, because
             // at the point we've gotten the interior cursor, but not yet constructed the slot cursor.
-            ColumnType cursorType = TransposeSchema.GetSlotType(col).ItemType;
+            ColumnType cursorType = _schema.GetSlotType(col).ItemType;
             RowCursor inputCursor = view.GetRowCursor(c => true);
             try
             {
@@ -783,8 +783,8 @@ private Transposer EnsureAndGetTransposer(int col)
                         _host.AssertValue(view);
                         _host.Assert(view.Schema.Count == 1);
                         var trans = _colTransposers[col] = Transposer.Create(_host, view, false, new int[] { 0 });
-                        _host.Assert(trans.TransposeSchema.ColumnCount == 1);
-                        _host.Assert(trans.TransposeSchema.GetSlotType(0).ValueCount == Schema[col].Type.ValueCount);
+                        _host.Assert(((ITransposeDataView)trans).TransposeSchema.ColumnCount == 1);
+                        _host.Assert(((ITransposeDataView)trans).TransposeSchema.GetSlotType(0).ValueCount == Schema[col].Type.ValueCount);
                     }
                 }
             }
@@ -845,7 +845,7 @@ private void Init(int col)
                 Ch.Assert(0 <= col && col < Schema.Count);
                 Ch.Assert(_colToActivesIndex[col] >= 0);
                 var type = Schema[col].Type;
-                Ch.Assert(_parent.TransposeSchema.GetSlotType(col).ValueCount == _parent._header.RowCount);
+                Ch.Assert(((ITransposeDataView)_parent).TransposeSchema.GetSlotType(col).ValueCount == _parent._header.RowCount);
                 Action<int> func = InitOne<int>;
                 if (type.IsVector)
                     func = InitVec<int>;

src/Microsoft.ML.Data/DataView/RowToRowMapperTransform.cs

@@ -92,7 +92,7 @@ internal RowToRowMapperTransform(IHostEnvironment env, IDataView input, IRowMapp
             Contracts.CheckValueOrNull(mapperFactory);
             _mapper = mapper;
             _mapperFactory = mapperFactory;
-            _bindings = new ColumnBindings(Schema.Create(input.Schema), mapper.GetOutputColumns());
+            _bindings = new ColumnBindings(input.Schema, mapper.GetOutputColumns());
         }
 
         [BestFriend]
@@ -110,7 +110,7 @@ private RowToRowMapperTransform(IHost host, ModelLoadContext ctx, IDataView inpu
             // _mapper
 
             ctx.LoadModel<IRowMapper, SignatureLoadRowMapper>(host, out _mapper, "Mapper", input.Schema);
-            _bindings = new ColumnBindings(Schema.Create(input.Schema), _mapper.GetOutputColumns());
+            _bindings = new ColumnBindings(input.Schema, _mapper.GetOutputColumns());
         }
 
         public static RowToRowMapperTransform Create(IHostEnvironment env, ModelLoadContext ctx, IDataView input)

src/Microsoft.ML.Data/DataView/Transposer.cs

@@ -21,7 +21,8 @@ namespace Microsoft.ML.Runtime.Data
     /// were not transposable before. Note that transposition is a somewhat slow and resource intensive
     /// operation.
     /// </summary>
-    public sealed class Transposer : ITransposeDataView, IDisposable
+    [BestFriend]
+    internal sealed class Transposer : ITransposeDataView, IDisposable
     {
         private readonly IHost _host;
         // The input view.
@@ -384,7 +385,7 @@ public override ValueGetter<VBuffer<TValue>> GetGetter<TValue>()
 
             public override VectorType GetSlotType()
             {
-                return _parent.TransposeSchema.GetSlotType(_col);
+                return ((ITransposeDataView)_parent).TransposeSchema.GetSlotType(_col);
             }
 
             protected abstract ValueGetter<VBuffer<T>> GetGetterCore();
@@ -1402,7 +1403,7 @@ public override ValueGetter<TValue> GetGetter<TValue>(int col)
         }
     }
 
-    public static class TransposerUtils
+    internal static class TransposerUtils
     {
         /// <summary>
         /// This is a convenience method that extracts a single slot value's vector,

src/Microsoft.ML.Data/EntryPoints/TransformModelImpl.cs

@@ -207,7 +207,7 @@ public CompositeRowToRowMapper(IExceptionContext ectx, IDataView chain, Schema r
                 _ectx.CheckValue(rootSchema, nameof(rootSchema));
 
                 _chain = chain;
-                _rootSchema = Schema.Create(rootSchema);
+                _rootSchema = rootSchema;
             }
 
             public static bool IsCompositeRowToRowMapper(IDataView chain)

src/Microsoft.ML.Data/Evaluators/MultiOutputRegressionEvaluator.cs

@@ -422,7 +422,7 @@ public static MultiOutputRegressionPerInstanceEvaluator Create(IHostEnvironment
             env.CheckValue(ctx, nameof(ctx));
             ctx.CheckAtModel(GetVersionInfo());
 
-            return new MultiOutputRegressionPerInstanceEvaluator(env, ctx, Schema.Create(schema));
+            return new MultiOutputRegressionPerInstanceEvaluator(env, ctx, schema);
         }
 
         public override void Save(ModelSaveContext ctx)

src/Microsoft.ML.Data/Evaluators/RankerEvaluator.cs

@@ -629,7 +629,7 @@ private sealed class Bindings : BindingsBase
                 private readonly int _truncationLevel;
                 private readonly MetadataUtils.MetadataGetter<VBuffer<ReadOnlyMemory<char>>> _slotNamesGetter;
 
-                public Bindings(IExceptionContext ectx, ISchema input, bool user, string labelCol, string scoreCol, string groupCol,
+                public Bindings(IExceptionContext ectx, Schema input, bool user, string labelCol, string scoreCol, string groupCol,
                     int truncationLevel)
                     : base(ectx, input, labelCol, scoreCol, groupCol, user, Ndcg, Dcg, MaxDcg)
                 {
@@ -736,7 +736,7 @@ public override void Save(ModelSaveContext ctx)
                 ctx.Writer.WriteDoubleArray(_labelGains);
             }
 
-            protected override BindingsBase GetBindings()
+            private protected override BindingsBase GetBindings()
             {
                 return _bindings;
             }

src/Microsoft.ML.Data/Scorers/GenericScorer.cs

@@ -161,7 +161,7 @@ internal GenericScorer(IHostEnvironment env, ScorerArgumentsBase args, IDataView
             var rowMapper = mapper as ISchemaBoundRowMapper;
             Host.CheckParam(rowMapper != null, nameof(mapper), "mapper should implement ISchemaBoundRowMapper");
             _bindings = Bindings.Create(data.Schema, rowMapper, args.Suffix);
-            OutputSchema = Schema.Create(_bindings);
+            OutputSchema = _bindings.AsSchema;
         }
 
         /// <summary>
@@ -171,7 +171,7 @@ private GenericScorer(IHostEnvironment env, GenericScorer transform, IDataView d
             : base(env, data, RegistrationName, transform.Bindable)
         {
             _bindings = transform._bindings.ApplyToSchema(env, data.Schema);
-            OutputSchema = Schema.Create(_bindings);
+            OutputSchema = _bindings.AsSchema;
         }
 
         /// <summary>
@@ -182,7 +182,7 @@ private GenericScorer(IHost host, ModelLoadContext ctx, IDataView input)
         {
             Contracts.AssertValue(ctx);
             _bindings = Bindings.Create(ctx, host, Bindable, input.Schema);
-            OutputSchema = Schema.Create(_bindings);
+            OutputSchema = _bindings.AsSchema;
         }
 
         /// <summary>

src/Microsoft.ML.Data/Scorers/PredictedLabelScorerBase.cs

@@ -307,15 +307,15 @@ private protected PredictedLabelScorerBase(ScorerArgumentsBase args, IHostEnviro
             var predColType = getPredColType(scoreType, rowMapper);
 
             Bindings = BindingsImpl.Create(data.Schema, rowMapper, args.Suffix, scoreColKind, scoreColIndex, predColType);
-            OutputSchema = Schema.Create(Bindings);
+            OutputSchema = Bindings.AsSchema;
         }
 
         protected PredictedLabelScorerBase(IHostEnvironment env, PredictedLabelScorerBase transform,
             IDataView newSource, string registrationName)
             : base(env, newSource, registrationName, transform.Bindable)
         {
             Bindings = transform.Bindings.ApplyToSchema(newSource.Schema, Bindable, env);
-            OutputSchema = Schema.Create(Bindings);
+            OutputSchema = Bindings.AsSchema;
         }
 
         [BestFriend]
@@ -329,7 +329,7 @@ private protected PredictedLabelScorerBase(IHost host, ModelLoadContext ctx, IDa
             Host.AssertValue(getPredColType);
 
             Bindings = BindingsImpl.Create(ctx, input.Schema, host, Bindable, outputTypeMatches, getPredColType);
-            OutputSchema = Schema.Create(Bindings);
+            OutputSchema = Bindings.AsSchema;
         }
 
         private protected override void SaveCore(ModelSaveContext ctx)

src/Microsoft.ML.Data/Scorers/RowToRowScorerBase.cs

@@ -86,7 +86,7 @@ private static bool[] GetActive(BindingsBase bindings, Func<int, bool> predicate
             Contracts.Assert(active.Length == bindings.ColumnCount);
 
             var activeInput = bindings.GetActiveInput(predicate);
-            Contracts.Assert(activeInput.Length == bindings.Input.ColumnCount);
+            Contracts.Assert(activeInput.Length == bindings.Input.Count);
 
             // Get a predicate that determines which Mapper outputs are active.
             predicateMapper = bindings.GetActiveMapperColumns(active);