Single sparse dimension short form

2 files changed, 66 insertions, 11 deletions

diff --git a/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java b/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
index 75690e45e15..e1b38264661 100644
--- a/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
+++ b/vespajlib/src/main/java/com/yahoo/tensor/serialization/JsonFormat.java
@@ -76,9 +76,12 @@ public class JsonFormat {
     }
 
     private static void decodeCells(Inspector cells, Tensor.Builder builder) {
-        if ( cells.type() != Type.ARRAY)
-            throw new IllegalArgumentException("Excepted 'cells' to contain an array, not " + cells.type());
-        cells.traverse((ArrayTraverser) (__, cell) -> decodeCell(cell, builder));
+        if ( cells.type() == Type.ARRAY)
+            cells.traverse((ArrayTraverser) (__, cell) -> decodeCell(cell, builder));
+        else if (cells.type() == Type.OBJECT)
+            cells.traverse((ObjectTraverser) (key, value) -> decodeSingleDimensionCell(key, value, builder));
+        else
+            throw new IllegalArgumentException("Excepted 'cells' to contain an array or obejct, not " + cells.type());
     }
 
     private static void decodeCell(Inspector cell, Tensor.Builder builder) {
@@ -91,6 +94,10 @@ public class JsonFormat {
         builder.cell(address, value.asDouble());
     }
 
+    private static void decodeSingleDimensionCell(String key, Inspector value, Tensor.Builder builder) {
+        builder.cell(asAddress(key, builder.type()), decodeNumeric(value));
+    }
+
     private static void decodeValues(Inspector values, Tensor.Builder builder) {
         if ( ! (builder instanceof IndexedTensor.BoundBuilder))
             throw new IllegalArgumentException("The 'values' field can only be used with dense tensors. " +
@@ -111,27 +118,36 @@ public class JsonFormat {
         if ( ! (builder instanceof MixedTensor.BoundBuilder))
             throw new IllegalArgumentException("The 'blocks' field can only be used with mixed tensors with bound dimensions. " +
                                                "Use 'cells' or 'values' instead");
-        if (values.type() != Type.ARRAY)
-            throw new IllegalArgumentException("Excepted 'blocks' to contain an array, not " + values.type());
-
         MixedTensor.BoundBuilder mixedBuilder = (MixedTensor.BoundBuilder) builder;
 
-        values.traverse((ArrayTraverser) (__, value) -> decodeBlock(value, mixedBuilder));
+        if (values.type() == Type.ARRAY)
+            values.traverse((ArrayTraverser) (__, value) -> decodeBlock(value, mixedBuilder));
+        else if (values.type() == Type.OBJECT)
+            values.traverse((ObjectTraverser) (key, value) -> decodeSingleDimensionBlock(key, value, mixedBuilder));
+        else
+            throw new IllegalArgumentException("Excepted 'blocks' to contain an array or object, not " + values.type());
     }
 
     private static void decodeBlock(Inspector block, MixedTensor.BoundBuilder mixedBuilder) {
         if (block.type() != Type.OBJECT)
             throw new IllegalArgumentException("Expected an item in a 'blocks' array to be an object, not " + block.type());
+        mixedBuilder.block(decodeAddress(block.field("address"), mixedBuilder.type().mappedSubtype()),
+                           decodeValues(block.field("values"), mixedBuilder));
+    }
 
-        TensorAddress mappedAddress = decodeAddress(block.field("address"), mixedBuilder.type().mappedSubtype());
+    private static void decodeSingleDimensionBlock(String key, Inspector value, MixedTensor.BoundBuilder mixedBuilder) {
+        if (value.type() != Type.ARRAY)
+            throw new IllegalArgumentException("Expected an item in a 'blocks' array to be an object, not " + value.type());
+        mixedBuilder.block(asAddress(key, mixedBuilder.type().mappedSubtype()),
+                           decodeValues(value, mixedBuilder));
+    }
 
-        Inspector valuesField = block.field("values");
+    private static double[] decodeValues(Inspector valuesField, MixedTensor.BoundBuilder mixedBuilder) {
         if (valuesField.type() != Type.ARRAY)
             throw new IllegalArgumentException("Expected a block to contain a 'values' array");
         double[] values = new double[(int)mixedBuilder.denseSubspaceSize()];
         valuesField.traverse((ArrayTraverser) (index, value) -> values[index] = decodeNumeric(value));
-
-        mixedBuilder.block(mappedAddress, values);
+        return values;
     }
 
     private static TensorAddress decodeAddress(Inspector addressField, TensorType type) {
@@ -142,6 +158,12 @@ public class JsonFormat {
         return builder.build();
     }
 
+    private static TensorAddress asAddress(String label, TensorType type) {
+        if (type.dimensions().size() != 1)
+            throw new IllegalArgumentException("Expected a tensor with a single dimension but got " + type);
+        return new TensorAddress.Builder(type).add(type.dimensions().get(0).name(), label).build();
+    }
+
     private static double decodeNumeric(Inspector numericField) {
         if (numericField.type() != Type.LONG && numericField.type() != Type.DOUBLE)
             throw new IllegalArgumentException("Excepted a number, not " + numericField.type());
diff --git a/vespajlib/src/test/java/com/yahoo/tensor/serialization/JsonFormatTestCase.java b/vespajlib/src/test/java/com/yahoo/tensor/serialization/JsonFormatTestCase.java
index 16f92289504..81de8a9db4c 100644
--- a/vespajlib/src/test/java/com/yahoo/tensor/serialization/JsonFormatTestCase.java
+++ b/vespajlib/src/test/java/com/yahoo/tensor/serialization/JsonFormatTestCase.java
@@ -32,6 +32,21 @@ public class JsonFormatTestCase {
     }
 
     @Test
+    public void testSingleSparseDimensionShortForm() {
+        Tensor.Builder builder = Tensor.Builder.of(TensorType.fromSpec("tensor(x{})"));
+        builder.cell().label("x", "a").value(2.0);
+        builder.cell().label("x", "c").value(3.0);
+        Tensor expected = builder.build();
+
+        String json= "{\"cells\":{" +
+                     "\"a\":2.0," +
+                     "\"c\":3.0" +
+                     "}}";
+        Tensor decoded = JsonFormat.decode(expected.type(), json.getBytes(StandardCharsets.UTF_8));
+        assertEquals(expected, decoded);
+    }
+
+    @Test
     public void testDenseTensor() {
         Tensor.Builder builder = Tensor.Builder.of(TensorType.fromSpec("tensor(x[2],y[2])"));
         builder.cell().label("x", 0).label("y", 0).value(2.0);
@@ -85,6 +100,24 @@ public class JsonFormatTestCase {
     }
 
     @Test
+    public void testMixedTensorInMixedFormWithSingleSparseDimensionShortForm() {
+        Tensor.Builder builder = Tensor.Builder.of(TensorType.fromSpec("tensor(x{},y[3])"));
+        builder.cell().label("x", 0).label("y", 0).value(2.0);
+        builder.cell().label("x", 0).label("y", 1).value(3.0);
+        builder.cell().label("x", 0).label("y", 2).value(4.0);
+        builder.cell().label("x", 1).label("y", 0).value(5.0);
+        builder.cell().label("x", 1).label("y", 1).value(6.0);
+        builder.cell().label("x", 1).label("y", 2).value(7.0);
+        Tensor expected = builder.build();
+        String mixedJson = "{\"blocks\":{" +
+                           "\"0\":[2.0,3.0,4.0]," +
+                           "\"1\":[5.0,6.0,7.0]" +
+                           "}}";
+        Tensor decoded = JsonFormat.decode(expected.type(), mixedJson.getBytes(StandardCharsets.UTF_8));
+        assertEquals(expected, decoded);
+    }
+
+    @Test
     public void testTooManyCells() {
         TensorType x2 = TensorType.fromSpec("tensor(x[2])");
         String json = "{\"cells\":[" +