Use Decimal formatter for Numeric ValuesSourceTypes (#54366)

Co-authored-by: Igor Motov <[email protected]>
Co-authored-by: Elastic Machine <[email protected]>

Author: 3 people

server/src/main/java/org/elasticsearch/search/aggregations/support/CoreValuesSourceType.java

@@ -75,6 +75,22 @@ public ValuesSource replaceMissing(ValuesSource valuesSource, Object rawMissing,
             Number missing = docValueFormat.parseDouble(rawMissing.toString(), false, nowSupplier);
             return MissingValues.replaceMissing((ValuesSource.Numeric) valuesSource, missing);
         }
+
+        @Override
+        public DocValueFormat getFormatter(String format, ZoneId tz) {
+            /* TODO: this silently ignores a timezone argument, whereas NumberFieldType#docValueFormat throws if given a time zone.
+                     Before we can solve this, we need to resolve https://github.com/elastic/elasticsearch/issues/47469 which deals
+                     with the fact that the same formatter is used for input and output values.  We want to support a use case in SQL
+                     (and elsewhere) that allows for passing a long value milliseconds since epoch into date aggregations.  In that case,
+                     the timezone is sensible as part of the bucket key format.
+             */
+            if (format == null) {
+                return DocValueFormat.RAW;
+            } else {
+                return new DocValueFormat.Decimal(format);
+            }
+
+        }
     },
     BYTES() {
         @Override

server/src/test/java/org/elasticsearch/search/aggregations/metrics/WeightedAvgAggregatorTests.java

@@ -354,6 +354,26 @@ public void testMultiWeight() throws IOException {
             "Use a script to combine multiple weights-per-doc into a single value."));
     }
 
+    public void testFormatter() throws IOException {
+        MultiValuesSourceFieldConfig valueConfig = new MultiValuesSourceFieldConfig.Builder().setFieldName("value_field").build();
+        MultiValuesSourceFieldConfig weightConfig = new MultiValuesSourceFieldConfig.Builder().setFieldName("weight_field").build();
+        WeightedAvgAggregationBuilder aggregationBuilder = new WeightedAvgAggregationBuilder("_name")
+            .value(valueConfig)
+            .weight(weightConfig)
+            .format("0.00%");
+        testCase(new MatchAllDocsQuery(), aggregationBuilder, iw -> {
+            iw.addDocument(Arrays.asList(new SortedNumericDocValuesField("value_field", 7),
+                new SortedNumericDocValuesField("weight_field", 1)));
+            iw.addDocument(Arrays.asList(new SortedNumericDocValuesField("value_field", 2),
+                new SortedNumericDocValuesField("weight_field", 1)));
+            iw.addDocument(Arrays.asList(new SortedNumericDocValuesField("value_field", 3),
+                new SortedNumericDocValuesField("weight_field", 1)));
+        }, avg -> {
+            assertEquals(4, avg.getValue(), 0);
+            assertTrue(AggregationInspectionHelper.hasValue(avg));
+            assertEquals("400.00%", avg.getValueAsString());
+        });
+    }
 
     public void testSummationAccuracy() throws IOException {
         // Summing up a normal array and expect an accurate value