[Rollup] Add scaled_float to allowed metric mapper types (elastic/x-pack-elasticsearch#4423)

We grab all the NumberFieldMappers to determine the whitelist of allowed
number types, but `scaled_float` is in a module so it isn't picked up
automatically.  This commit adds `scaled_float` to the whitelist
manually.

Original commit: elastic/x-pack-elasticsearch@fb354403159bcb75d2264d885f01f139f187083a

Author: polyfractal

plugin/core/src/main/java/org/elasticsearch/xpack/core/rollup/job/MetricConfig.java

@@ -67,9 +67,14 @@ public class MetricConfig implements Writeable, ToXContentFragment {
     private static final ParseField AVG = new ParseField("avg");
     private static final ParseField VALUE_COUNT = new ParseField("value_count");
 
-    private static final List<String> MAPPER_TYPES = Stream.of(NumberFieldMapper.NumberType.values())
-            .map(NumberFieldMapper.NumberType::typeName)
-            .collect(Collectors.toList());
+    private static final List<String> MAPPER_TYPES;
+    static {
+        List<String> types = Stream.of(NumberFieldMapper.NumberType.values())
+                .map(NumberFieldMapper.NumberType::typeName)
+                .collect(Collectors.toList());
+        types.add("scaled_float"); // have to add manually since scaled_float is in a module
+        MAPPER_TYPES = types;
+    }
 
     public static final ConstructingObjectParser<MetricConfig, Void> PARSER = new ConstructingObjectParser<>(
             NAME, a -> new MetricConfig((String)a[0], (List<String>) a[1]));

plugin/core/src/test/java/org/elasticsearch/xpack/core/rollup/job/MetricsConfigSerializingTests.java

@@ -119,6 +119,77 @@ public void testValidateMatchingField() throws IOException {
                 .build();
         config.validateMappings(responseMap, e);
         assertThat(e.validationErrors().size(), equalTo(0));
+
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("double", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("float", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("short", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("byte", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("half_float", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("scaled_float", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
+
+        fieldCaps = mock(FieldCapabilities.class);
+        when(fieldCaps.isAggregatable()).thenReturn(true);
+        responseMap.put("my_field", Collections.singletonMap("integer", fieldCaps));
+        config = new MetricConfig.Builder()
+                .setField("my_field")
+                .setMetrics(Collections.singletonList("max"))
+                .build();
+        config.validateMappings(responseMap, e);
+        assertThat(e.validationErrors().size(), equalTo(0));
     }
 
 }