Address feature and deprecation Warnings (mostly provideData)

scala-package/core/src/main/scala/org/apache/mxnet/ExecutorManager.scala

@@ -395,17 +395,17 @@ private[mxnet] object ExecutorManager {
  * @param paramNames Names of all trainable parameters.
  * @param ctx List of devices for training (data parallel)
  * @param slices Describes how the data parallel splits data into different devices.
- * @param providedData training data shapes
- * @param providedLabel training label shapes
+ * @param providedDataDesc training data descriptions
+ * @param providedLabelDesc training label descriptions
  * @param sharedGroup: DataParallelExecutorGroup
  *                   An existing executor group, if to share parameters with it.
  *
  */
 private class DataParallelExecutorGroup private(sym: Symbol,
                                 argNames: IndexedSeq[String], paramNames: Set[String],
                                 ctx: Array[Context], private val slices: Array[(Int, Int)],
-                                providedData: Map[String, Shape],
-                                providedLabel: Map[String, Shape],
+                                providedDataDesc: IndexedSeq[DataDesc],
+                                providedLabelDesc: IndexedSeq[DataDesc],
                                 sharedGroup: DataParallelExecutorGroup)  {
   // make sure the architecture is valid
   ExecutorManager.checkArguments(sym)
@@ -417,8 +417,8 @@ private class DataParallelExecutorGroup private(sym: Symbol,
       sharedGroup.sharedDataArrays
     }
 
-  private[mxnet] val dataNames = providedData.map { case (k, _) => k }.toList
-  private[mxnet] val labelNames = providedLabel.map { case (k, _) => k }.toList
+  private[mxnet] val dataNames = providedDataDesc.map(_.name).toList
+  private[mxnet] val labelNames = providedLabelDesc.map(_.name).toList
   private[mxnet] val auxNames = sym.listAuxiliaryStates()
   private[mxnet] val paramIdx = argNames.zipWithIndex
     .filter { case (name, i) => paramNames.contains(name) }
@@ -428,9 +428,10 @@ private class DataParallelExecutorGroup private(sym: Symbol,
   private[mxnet] val trainExecs: Array[Executor] =
     ctx.zipWithIndex.map { case (ctxi, i) =>
       val dataShapes =
-        (providedData ++ providedLabel) map { case (name, shape) =>
-          name -> (Shape(slices(i)._2 - slices(i)._1) ++ shape.slice(1, shape.length))
-        }
+        (providedDataDesc ++ providedLabelDesc).map( desc => {
+          desc.name ->
+            (Shape(slices(i)._2 - slices(i)._1) ++ desc.shape.slice(1, desc.shape.length))
+        }).toMap
       val sharedExec: Executor = if (sharedGroup == null) null else sharedGroup.trainExecs(i)
       ExecutorManager.bindExec(sym, ctxi, dataShapes, paramNamesComb,
         needGrad = true, baseExec = sharedExec,
@@ -479,15 +480,15 @@ private class DataParallelExecutorGroup private(sym: Symbol,
       trainData: DataIter,
       sharedGroup: DataParallelExecutorGroup) {
     this(sym, argNames, paramNames, ctx, slices,
-      trainData.provideData, trainData.provideLabel, sharedGroup)
+      trainData.provideDataDesc, trainData.provideLabelDesc, sharedGroup)
   }
 
   def this(sym: Symbol,
            argNames: IndexedSeq[String], paramNames: Set[String],
            ctx: Array[Context], slices: Array[(Int, Int)],
            trainData: DataIter) {
     this(sym, argNames, paramNames, ctx, slices,
-      trainData.provideData, trainData.provideLabel, null)
+      trainData.provideDataDesc, trainData.provideLabelDesc, null)
   }
 
   /**
@@ -509,15 +510,15 @@ private class DataParallelExecutorGroup private(sym: Symbol,
       trainData: DataBatch,
       sharedGroup: DataParallelExecutorGroup) {
     this(sym, argNames, paramNames, ctx, slices,
-      trainData.provideData, trainData.provideLabel, sharedGroup)
+      trainData.provideDataDesc, trainData.provideLabelDesc, sharedGroup)
   }
 
   def this(sym: Symbol,
            argNames: IndexedSeq[String], paramNames: Set[String],
            ctx: Array[Context], slices: Array[(Int, Int)],
            trainData: DataBatch) {
     this(sym, argNames, paramNames, ctx, slices,
-      trainData.provideData, trainData.provideLabel, null)
+      trainData.provideDataDesc, trainData.provideLabelDesc, null)
   }
 
   // load data and labels into arrays

scala-package/core/src/main/scala/org/apache/mxnet/FeedForward.scala

@@ -129,11 +129,11 @@ class FeedForward private(
   // Initialize weight parameters and auxiliary states
   // The NDArrays associated with the _argParms and _auxParams are not disposed instead
   // they are passed a outer scope if available.
-  private def initParams(inputShapes: Map[String, Shape], overwrite: Boolean = false)
+  private def initParams(inputShapes: IndexedSeq[DataDesc], overwrite: Boolean = false)
   : (IndexedSeq[String], IndexedSeq[String], IndexedSeq[String]) = {
     val (argShapes, _, auxShapes) = symbol.inferShape(inputShapes)
     val argNames = symbol.listArguments()
-    val inputNames = inputShapes.keys.toSet
+    val inputNames = inputShapes.map(_.name).toSet
     val paramNames = argNames.filter(!inputNames.contains(_))
     val auxNames = symbol.listAuxiliaryStates()
 
@@ -179,7 +179,7 @@ class FeedForward private(
   }
 
   // Initialize the predictor module for running prediction.
-  private def initPredictor(inputShapes: Map[String, Shape]): Unit = {
+  private def initPredictor(inputShapes: IndexedSeq[DataDesc]): Unit = {
     var shouldInit = true
     if (this.predExec != null) {
       val (argShapes, _, _) = symbol.inferShape(inputShapes)
@@ -193,7 +193,7 @@ class FeedForward private(
     }
     if(shouldInit) {
       // for now only use the first device
-      val predExec = symbol.simpleBind(ctx(0), gradReq = "null", shapeDict = inputShapes)
+      val predExec = symbol.simpleBind(ctx(0), gradReq = "null", inputShapes)
       predExec.copyParamsFrom(_argParams, _auxParams)
       ExecutorManager.checkArguments(symbol)
       this.predExec = predExec
@@ -233,8 +233,8 @@ class FeedForward private(
    */
   def predict(data: DataIter, numBatch: Int = -1): Array[NDArray] = {
     data.reset()
-    val dataShapes = data.provideData
-    val dataNames = dataShapes.map(_._1).toArray
+    val dataShapes = data.provideDataDesc
+    val dataNames = dataShapes.map(_.name).toArray
     initPredictor(dataShapes)
     val batchSize = data.batchSize
     val dataArrays = dataNames.map(predExec.argDict(_))
@@ -363,7 +363,7 @@ class FeedForward private(
       this.symbol = symGen.generate(trainData.defaultBucketKey)
       checkArguments()
     }
-    initParams(trainData.provideData ++ trainData.provideLabel)
+    initParams(trainData.provideDataDesc ++ trainData.provideLabelDesc)
   }
 
   private def fit(trainData: DataIter, evalData: DataIter, evalMetric: EvalMetric = new Accuracy(),

scala-package/core/src/main/scala/org/apache/mxnet/IO.scala

@@ -141,28 +141,46 @@ class DataBatch(val data: IndexedSeq[NDArray],
                 val pad: Int,
                 // the key for the bucket that should be used for this batch,
                 // for bucketing io only
-                val bucketKey: AnyRef,
+                val bucketKey: AnyRef = null,
                 // use DataDesc to indicate the order of data/label loading
                 // (must match the order of input data/label)
-                private val providedDataDesc: IndexedSeq[DataDesc],
-                private val providedLabelDesc: IndexedSeq[DataDesc]) {
+                private val providedDataDesc: IndexedSeq[DataDesc] = null,
+                private val providedLabelDesc: IndexedSeq[DataDesc] = null) {
   // TODO: change the data/label type into IndexedSeq[(NDArray, DataDesc)]
   // However, since the data and label can be accessed publicly (no getter and setter)
   // the change on this will break BC
+
+  @deprecated("Use provideDataDesc and provideDataLabel instead", "1.3.0")
+  def this(data: IndexedSeq[NDArray],
+           label: IndexedSeq[NDArray],
+           index: IndexedSeq[Long],
+           pad: Int,
+           // the key for the bucket that should be used for this batch,
+           // for bucketing io only
+           bucketKey: AnyRef,
+           // use ListMap to indicate the order of data/label loading
+           // (must match the order of input data/label)
+           providedData: ListMap[String, Shape]) {
+    this(data, label, index, pad, bucketKey,
+      DataDesc.ListMap2Descs(providedData))
+  }
+
+  @deprecated("Use provideDataDesc and provideDataLabel instead", "1.3.0")
   def this(data: IndexedSeq[NDArray],
             label: IndexedSeq[NDArray],
             index: IndexedSeq[Long],
             pad: Int,
             // the key for the bucket that should be used for this batch,
             // for bucketing io only
-            bucketKey: AnyRef = null,
+            bucketKey: AnyRef,
             // use ListMap to indicate the order of data/label loading
             // (must match the order of input data/label)
-            providedData: ListMap[String, Shape] = null,
-            providedLabel: ListMap[String, Shape] = null) {
+            providedData: ListMap[String, Shape],
+            providedLabel: ListMap[String, Shape]) {
     this(data, label, index, pad, bucketKey,
       DataDesc.ListMap2Descs(providedData), DataDesc.ListMap2Descs(providedLabel))
   }
+
   /**
    * Dispose its data and labels
    * The object shall never be used after it is disposed.
@@ -177,6 +195,7 @@ class DataBatch(val data: IndexedSeq[NDArray],
   }
 
   // The name and shape of data
+  @deprecated("Use provideDataDesc instead", "1.3.0")
   def provideData: ListMap[String, Shape] = {
     var temp = ListMap[String, Shape]()
     if (providedDataDesc == null) null
@@ -187,6 +206,7 @@ class DataBatch(val data: IndexedSeq[NDArray],
   }
 
   // The name and shape of label
+  @deprecated("Use provideLabelDesc instead", "1.3.0")
   def provideLabel: ListMap[String, Shape] = {
     var temp = ListMap[String, Shape]()
     if (providedLabelDesc == null) null
@@ -311,8 +331,7 @@ abstract class DataIter extends Iterator[DataBatch] {
    */
   @throws(classOf[NoSuchElementException])
   def next(): DataBatch = {
-    new DataBatch(getData(), getLabel(), getIndex(), getPad(),
-      null, null, null)
+    new DataBatch(getData(), getLabel(), getIndex(), getPad())
   }
 
   /**

scala-package/core/src/main/scala/org/apache/mxnet/Symbol.scala

@@ -21,6 +21,7 @@ import org.apache.mxnet.Base._
 import org.apache.mxnet.DType.DType
 import org.slf4j.{Logger, LoggerFactory}
 
+import scala.collection.mutable
 import scala.collection.mutable.{ArrayBuffer, ListBuffer}
 import scala.language.implicitConversions
 
@@ -209,6 +210,33 @@ class Symbol private(private[mxnet] val handle: SymbolHandle) extends NativeReso
     }
   }
 
+  /**
+    * Infer the shape of outputs and arguments of given known shapes of arguments.
+    * User can either pass in the known shapes in positional way or keyword argument way.
+    * Tuple of Nones is returned if there is not enough information passed in.
+    * An error will be raised if there is inconsistency found in the known shapes passed in.
+    * @param args Provide a list of DataDesc containing the shapes to resolve
+    * @return
+    * argShapes List of shapes of arguments. The order is in the same order as list_arguments()
+    * outShapes List of shapes of outputs. The order is in the same order as list_outputs()
+    * auxShapes List of shapes of outputs. The order is in the same order as list_auxiliary()
+    */
+  def inferShape(args: IndexedSeq[DataDesc]):
+  (IndexedSeq[Shape], IndexedSeq[Shape], IndexedSeq[Shape]) = {
+    val keys = ArrayBuffer.empty[String]
+    val indPtr = ArrayBuffer(0)
+    val sdata = ArrayBuffer.empty[Int]
+    args.foreach { arg =>
+      val shape = arg.shape
+      if (shape != null) {
+        keys += arg.name
+        sdata ++= shape.toVector
+        indPtr += sdata.size
+      }
+    }
+    inferShape(keys.toArray, indPtr.toArray, sdata.toArray)
+  }
+
   /**
    * Infer the shape of outputs and arguments of given known shapes of arguments.
    * User can either pass in the known shapes in positional way or keyword argument way.
@@ -389,6 +417,29 @@ class Symbol private(private[mxnet] val handle: SymbolHandle) extends NativeReso
     checkCall(_LIB.mxSymbolCompose(handle, name, keys, args))
   }
 
+  /**
+    * Bind current symbol to get an executor, allocate all the ndarrays needed.
+    * Allows specifying data types.
+    * This function will ask user to pass in ndarray of position
+    * they like to bind to, and it will automatically allocate the ndarray
+    * for arguments and auxiliary states that user did not specify explicitly.
+    *
+    * @param ctx The device context the generated executor to run on.
+    * @param gradReq {'write', 'add', 'null'}, or list of str or dict of str to str, optional
+    *                Specifies how we should update the gradient to the args_grad.
+    *                - 'write' means everytime gradient is write to specified args_grad NDArray.
+    *                - 'add' means everytime gradient is add to the specified NDArray.
+    *                - 'null' means no action is taken, the gradient may not be calculated.
+    * @param dataDesc List of dataDescriptors
+    * @return The generated Executor
+    */
+  def simpleBind(ctx: Context, gradReq: String,
+                 descs: IndexedSeq[DataDesc]) : Executor = {
+    val (shapes, types) = descs.map(desc =>
+      ( desc.name -> desc.shape, desc.name -> desc.dtype )).unzip
+    simpleBind(ctx, gradReq, shapes.toMap, types.toMap)
+  }
+
   /**
    * Bind current symbol to get an executor, allocate all the ndarrays needed.
    * Allows specifying data types.

scala-package/core/src/main/scala/org/apache/mxnet/io/MXDataIter.scala

@@ -107,8 +107,7 @@ private[mxnet] class MXDataIter(private[mxnet] val handle: DataIterHandle,
     checkCall(_LIB.mxDataIterNext(handle, next))
     if (next.value > 0) {
       currentBatch = new DataBatch(data = getData(), label = getLabel(),
-        index = getIndex(), pad = getPad(),
-        null, null, null)
+        index = getIndex(), pad = getPad())
     } else {
       currentBatch = null
     }

scala-package/core/src/main/scala/org/apache/mxnet/io/NDArrayIter.scala

@@ -161,8 +161,7 @@ class NDArrayIter(data: IndexedSeq[(DataDesc, NDArray)],
   override def next(): DataBatch = {
     if (hasNext) {
       cursor += dataBatchSize
-      new DataBatch(getData(), getLabel(), getIndex(), getPad(),
-        null, null, null)
+      new DataBatch(getData(), getLabel(), getIndex(), getPad())
     } else {
       throw new NoSuchElementException
     }