[Transform] add support for filter aggregation (#52483)

add support for filter aggregations, refactor code for sub-aggregation support in mapping
deduction

fixes #52151

x-pack/plugin/transform/qa/single-node-tests/src/test/java/org/elasticsearch/xpack/transform/integration/TransformPivotRestIT.java

@@ -1173,6 +1173,94 @@ public class TransformPivotRestIT extends TransformRestTestCase {
         assertEquals(5, actual.longValue());
     }
 
+    public void testPivotWithFilter() throws Exception {
+        String transformId = "filter_pivot";
+        String transformIndex = "filter_pivot_reviews";
+        setupDataAccessRole(DATA_ACCESS_ROLE, REVIEWS_INDEX_NAME, transformIndex);
+        final Request createTransformRequest = createRequestWithAuth(
+            "PUT",
+            getTransformEndpoint() + transformId,
+            BASIC_AUTH_VALUE_TRANSFORM_ADMIN_WITH_SOME_DATA_ACCESS
+        );
+        String config = "{"
+            + " \"source\": {\"index\":\""
+            + REVIEWS_INDEX_NAME
+            + "\"},"
+            + " \"dest\": {\"index\":\""
+            + transformIndex
+            + "\"},"
+            + " \"frequency\": \"1s\","
+            + " \"pivot\": {"
+            + "   \"group_by\": {"
+            + "     \"reviewer\": {"
+            + "       \"terms\": {"
+            + "         \"field\": \"user_id\""
+            + " } } },"
+            + "   \"aggregations\": {"
+            + "     \"top_ratings\": {"
+            + "       \"filter\": {"
+            + "         \"range\": {"
+            + "            \"stars\": {"
+            + "               \"gte\": 4 "
+            + "         } } } },"
+            + "     \"top_ratings_detail\": {"
+            + "       \"filter\": {"
+            + "         \"range\": {"
+            + "            \"stars\": {"
+            + "               \"gte\": 4"
+            + "         } } },"
+            + "         \"aggregations\": {"
+            + "            \"unique_count\": {"
+            + "               \"cardinality\": {"
+            + "                  \"field\": \"business_id\""
+            + "         } },"
+            + "            \"max\": {"
+            + "               \"max\": {"
+            + "                  \"field\": \"stars\""
+            + "         } },"
+            + "            \"min\": {"
+            + "               \"min\": {"
+            + "                  \"field\": \"stars\""
+            + "         } }"
+            + " } } } }"
+            + "}";
+
+        createTransformRequest.setJsonEntity(config);
+        Map<String, Object> createTransformResponse = entityAsMap(client().performRequest(createTransformRequest));
+        assertThat(createTransformResponse.get("acknowledged"), equalTo(Boolean.TRUE));
+
+        startAndWaitForTransform(transformId, transformIndex);
+        assertTrue(indexExists(transformIndex));
+        // get and check some users
+
+        Map<String, Object> searchResult = getAsMap(transformIndex + "/_search?q=reviewer:user_4");
+        assertEquals(1, XContentMapValues.extractValue("hits.total.value", searchResult));
+
+        Number actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings", searchResult)).get(0);
+        assertEquals(29, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.min", searchResult)).get(0);
+        assertEquals(4, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.max", searchResult)).get(0);
+        assertEquals(5, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.unique_count", searchResult)).get(
+            0
+        );
+        assertEquals(4, actual.longValue());
+
+        searchResult = getAsMap(transformIndex + "/_search?q=reviewer:user_2");
+        assertEquals(1, XContentMapValues.extractValue("hits.total.value", searchResult));
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings", searchResult)).get(0);
+        assertEquals(19, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.min", searchResult)).get(0);
+        assertEquals(4, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.max", searchResult)).get(0);
+        assertEquals(5, actual.longValue());
+        actual = (Number) ((List<?>) XContentMapValues.extractValue("hits.hits._source.top_ratings_detail.unique_count", searchResult)).get(
+            0
+        );
+        assertEquals(3, actual.longValue());
+    }
+
     private void createDateNanoIndex(String indexName, int numDocs) throws IOException {
         // create mapping
         try (XContentBuilder builder = jsonBuilder()) {

x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/transforms/pivot/AggregationResultUtils.java

@@ -16,6 +16,7 @@ import org.elasticsearch.common.geo.parsers.ShapeParser;
 import org.elasticsearch.search.aggregations.Aggregation;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
 import org.elasticsearch.search.aggregations.PipelineAggregationBuilder;
+import org.elasticsearch.search.aggregations.bucket.SingleBucketAggregation;
 import org.elasticsearch.search.aggregations.bucket.composite.CompositeAggregation;
 import org.elasticsearch.search.aggregations.metrics.GeoBounds;
 import org.elasticsearch.search.aggregations.metrics.GeoCentroid;
@@ -50,6 +51,7 @@ public final class AggregationResultUtils {
         tempMap.put(GeoCentroid.class.getName(), new GeoCentroidAggExtractor());
         tempMap.put(GeoBounds.class.getName(), new GeoBoundsAggExtractor());
         tempMap.put(Percentiles.class.getName(), new PercentilesAggExtractor());
+        tempMap.put(SingleBucketAggregation.class.getName(), new SingleBucketAggExtractor());
         TYPE_VALUE_EXTRACTOR_MAP = Collections.unmodifiableMap(tempMap);
     }
 
@@ -94,9 +96,8 @@ public final class AggregationResultUtils {
                 // present at all in the `bucket.getAggregations`. This could occur in the case of a `bucket_selector` agg, which
                 // does not calculate a value, but instead manipulates other results.
                 if (aggResult != null) {
-                    final String fieldType = fieldTypeMap.get(aggName);
                     AggValueExtractor extractor = getExtractor(aggResult);
-                    updateDocument(document, aggName, extractor.value(aggResult, fieldType));
+                    updateDocument(document, aggName, extractor.value(aggResult, fieldTypeMap, ""));
                 }
             }
 
@@ -117,6 +118,8 @@ public final class AggregationResultUtils {
             return TYPE_VALUE_EXTRACTOR_MAP.get(GeoBounds.class.getName());
         } else if (aggregation instanceof Percentiles) {
             return TYPE_VALUE_EXTRACTOR_MAP.get(Percentiles.class.getName());
+        } else if (aggregation instanceof SingleBucketAggregation) {
+            return TYPE_VALUE_EXTRACTOR_MAP.get(SingleBucketAggregation.class.getName());
         } else {
             // Execution should never reach this point!
             // Creating transforms with unsupported aggregations shall not be possible
@@ -175,17 +178,19 @@ public final class AggregationResultUtils {
     }
 
     interface AggValueExtractor {
-        Object value(Aggregation aggregation, String fieldType);
+        Object value(Aggregation aggregation, Map<String, String> fieldTypeMap, String lookupFieldPrefix);
     }
 
     static class SingleValueAggExtractor implements AggValueExtractor {
         @Override
-        public Object value(Aggregation agg, String fieldType) {
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
             SingleValue aggregation = (SingleValue) agg;
             // If the double is invalid, this indicates sparse data
             if (Numbers.isValidDouble(aggregation.value()) == false) {
                 return null;
             }
+
+            String fieldType = fieldTypeMap.get(lookupFieldPrefix.isEmpty() ? agg.getName() : lookupFieldPrefix + "." + agg.getName());
             // If the type is numeric or if the formatted string is the same as simply making the value a string,
             // gather the `value` type, otherwise utilize `getValueAsString` so we don't lose formatted outputs.
             if (isNumericType(fieldType) || aggregation.getValueAsString().equals(String.valueOf(aggregation.value()))) {
@@ -198,7 +203,7 @@ public final class AggregationResultUtils {
 
     static class PercentilesAggExtractor implements AggValueExtractor {
         @Override
-        public Object value(Aggregation agg, String fieldType) {
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
             Percentiles aggregation = (Percentiles) agg;
 
             HashMap<String, Double> percentiles = new HashMap<>();
@@ -211,9 +216,34 @@ public final class AggregationResultUtils {
         }
     }
 
+    static class SingleBucketAggExtractor implements AggValueExtractor {
+        @Override
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
+            SingleBucketAggregation aggregation = (SingleBucketAggregation) agg;
+
+            if (aggregation.getAggregations().iterator().hasNext() == false) {
+                return aggregation.getDocCount();
+            }
+
+            HashMap<String, Object> nested = new HashMap<>();
+            for (Aggregation subAgg : aggregation.getAggregations()) {
+                nested.put(
+                    subAgg.getName(),
+                    getExtractor(subAgg).value(
+                        subAgg,
+                        fieldTypeMap,
+                        lookupFieldPrefix.isEmpty() ? agg.getName() : lookupFieldPrefix + "." + agg.getName()
+                    )
+                );
+            }
+
+            return nested;
+        }
+    }
+
     static class ScriptedMetricAggExtractor implements AggValueExtractor {
         @Override
-        public Object value(Aggregation agg, String fieldType) {
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
             ScriptedMetric aggregation = (ScriptedMetric) agg;
             return aggregation.aggregation();
         }
@@ -221,7 +251,7 @@ public final class AggregationResultUtils {
 
     static class GeoCentroidAggExtractor implements AggValueExtractor {
         @Override
-        public Object value(Aggregation agg, String fieldType) {
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
             GeoCentroid aggregation = (GeoCentroid) agg;
             // if the account is `0` iff there is no contained centroid
             return aggregation.count() > 0 ? aggregation.centroid().toString() : null;
@@ -230,7 +260,7 @@ public final class AggregationResultUtils {
 
     static class GeoBoundsAggExtractor implements AggValueExtractor {
         @Override
-        public Object value(Aggregation agg, String fieldType) {
+        public Object value(Aggregation agg, Map<String, String> fieldTypeMap, String lookupFieldPrefix) {
             GeoBounds aggregation = (GeoBounds) agg;
             if (aggregation.bottomRight() == null || aggregation.topLeft() == null) {
                 return null;

x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/transforms/pivot/Aggregations.java

@@ -6,15 +6,19 @@
 
 package org.elasticsearch.xpack.transform.transforms.pivot;
 
+import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
 import org.elasticsearch.search.aggregations.metrics.PercentilesAggregationBuilder;
+import org.elasticsearch.search.aggregations.support.ValuesSourceAggregationBuilder;
 import org.elasticsearch.xpack.transform.utils.OutputFieldNameConverter;
 
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Set;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -52,7 +56,6 @@ public final class Aggregations {
         "date_range",
         "diversified_sampler",
         "extended_stats", // https://github.com/elastic/elasticsearch/issues/51925
-        "filter", // https://github.com/elastic/elasticsearch/issues/52151
         "filters",
         "geo_distance",
         "geohash_grid",
@@ -102,7 +105,8 @@ public final class Aggregations {
         WEIGHTED_AVG("weighted_avg", DYNAMIC),
         BUCKET_SELECTOR("bucket_selector", DYNAMIC),
         BUCKET_SCRIPT("bucket_script", DYNAMIC),
-        PERCENTILES("percentiles", DOUBLE);
+        PERCENTILES("percentiles", DOUBLE),
+        FILTER("filter", LONG);
 
         private final String aggregationType;
         private final String targetMapping;
@@ -146,28 +150,68 @@ public final class Aggregations {
         AggregationType agg = AggregationType.valueOf(aggregationType.toUpperCase(Locale.ROOT));
 
         if (agg.getTargetMapping().equals(SOURCE)) {
+
+            if (sourceType == null) {
+                // this should never happen and would mean a bug in the calling code, the error is logged in {@link
+                // org.elasticsearch.xpack.transform.transforms.pivot.SchemaUtil#resolveMappings()}
+                return null;
+            }
+
             // scaled float requires an additional parameter "scaling_factor", which we do not know, therefore we fallback to float
             if (sourceType.equals(SCALED_FLOAT)) {
                 return FLOAT;
             }
+
             return sourceType;
         }
 
         return agg.getTargetMapping();
     }
 
-    public static Map<String, String> getAggregationOutputTypes(AggregationBuilder agg) {
+    public static Tuple<Map<String, String>, Map<String, String>> getAggregationInputAndOutputTypes(AggregationBuilder agg) {
         if (agg instanceof PercentilesAggregationBuilder) {
             PercentilesAggregationBuilder percentilesAgg = (PercentilesAggregationBuilder) agg;
 
             // note: eclipse does not like p -> agg.getType()
             // the merge function (p1, p2) -> p1 ignores duplicates
-            return Arrays.stream(percentilesAgg.percentiles())
+            return new Tuple<>(
+                Collections.emptyMap(),
+                Arrays.stream(percentilesAgg.percentiles())
                     .mapToObj(OutputFieldNameConverter::fromDouble)
-                .collect(Collectors.toMap(p -> agg.getName() + "." + p, p -> { return agg.getType(); }, (p1, p2) -> p1));
+                    .collect(Collectors.toMap(p -> agg.getName() + "." + p, p -> { return agg.getType(); }, (p1, p2) -> p1))
+            );
         }
-        // catch all
-        return Collections.singletonMap(agg.getName(), agg.getType());
+
+        if (agg instanceof ValuesSourceAggregationBuilder) {
+            ValuesSourceAggregationBuilder<?, ?> valueSourceAggregation = (ValuesSourceAggregationBuilder<?, ?>) agg;
+            return new Tuple<>(
+                Collections.singletonMap(valueSourceAggregation.getName(), valueSourceAggregation.field()),
+                Collections.singletonMap(agg.getName(), agg.getType())
+            );
+        }
+
+        // does the agg have sub aggregations?
+        if (agg.getSubAggregations().size() > 0) {
+            HashMap<String, String> outputTypes = new HashMap<>();
+            HashMap<String, String> inputTypes = new HashMap<>();
+
+            for (AggregationBuilder subAgg : agg.getSubAggregations()) {
+                Tuple<Map<String, String>, Map<String, String>> subAggregationTypes = getAggregationInputAndOutputTypes(subAgg);
+
+                for (Entry<String, String> subAggOutputType : subAggregationTypes.v2().entrySet()) {
+                    outputTypes.put(String.join(".", agg.getName(), subAggOutputType.getKey()), subAggOutputType.getValue());
+                }
+
+                for (Entry<String, String> subAggInputType : subAggregationTypes.v1().entrySet()) {
+                    inputTypes.put(String.join(".", agg.getName(), subAggInputType.getKey()), subAggInputType.getValue());
+                }
+            }
+
+            return new Tuple<>(inputTypes, outputTypes);
+        }
+
+        // catch all in case no special handling required
+        return new Tuple<>(Collections.emptyMap(), Collections.singletonMap(agg.getName(), agg.getType()));
     }
 
 }

x-pack/plugin/transform/src/main/java/org/elasticsearch/xpack/transform/transforms/pivot/SchemaUtil.java

@@ -14,12 +14,10 @@ import org.elasticsearch.action.fieldcaps.FieldCapabilitiesRequest;
 import org.elasticsearch.action.fieldcaps.FieldCapabilitiesResponse;
 import org.elasticsearch.action.support.IndicesOptions;
 import org.elasticsearch.client.Client;
+import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.index.mapper.NumberFieldMapper;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
 import org.elasticsearch.search.aggregations.PipelineAggregationBuilder;
-import org.elasticsearch.search.aggregations.metrics.ScriptedMetricAggregationBuilder;
-import org.elasticsearch.search.aggregations.support.MultiValuesSourceAggregationBuilder;
-import org.elasticsearch.search.aggregations.support.ValuesSourceAggregationBuilder;
 import org.elasticsearch.xpack.core.ClientHelper;
 import org.elasticsearch.xpack.core.transform.transforms.pivot.PivotConfig;
 
@@ -76,17 +74,9 @@ public final class SchemaUtil {
             .forEach((destinationFieldName, group) -> { fieldNamesForGrouping.put(destinationFieldName, group.getField()); });
 
         for (AggregationBuilder agg : config.getAggregationConfig().getAggregatorFactories()) {
-            if (agg instanceof ValuesSourceAggregationBuilder) {
-                ValuesSourceAggregationBuilder<?, ?> valueSourceAggregation = (ValuesSourceAggregationBuilder<?, ?>) agg;
-                aggregationSourceFieldNames.put(valueSourceAggregation.getName(), valueSourceAggregation.field());
-                aggregationTypes.putAll(Aggregations.getAggregationOutputTypes(valueSourceAggregation));
-            } else if (agg instanceof ScriptedMetricAggregationBuilder || agg instanceof MultiValuesSourceAggregationBuilder) {
-                aggregationTypes.putAll(Aggregations.getAggregationOutputTypes(agg));
-            } else {
-                // execution should not reach this point
-                listener.onFailure(new RuntimeException("Unsupported aggregation type [" + agg.getType() + "]"));
-                return;
-            }
+            Tuple<Map<String, String>, Map<String, String>> inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(agg);
+            aggregationSourceFieldNames.putAll(inputAndOutputTypes.v1());
+            aggregationTypes.putAll(inputAndOutputTypes.v2());
         }
 
         // For pipeline aggs, since they are referencing other aggregations in the payload, they do not have any

x-pack/plugin/transform/src/test/java/org/elasticsearch/xpack/transform/transforms/pivot/AggregationSchemaAndResultTests.java

@@ -0,0 +1,287 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+package org.elasticsearch.xpack.transform.transforms.pivot;
+
+import org.elasticsearch.action.ActionListener;
+import org.elasticsearch.action.ActionRequest;
+import org.elasticsearch.action.ActionResponse;
+import org.elasticsearch.action.ActionType;
+import org.elasticsearch.action.LatchedActionListener;
+import org.elasticsearch.action.fieldcaps.FieldCapabilities;
+import org.elasticsearch.action.fieldcaps.FieldCapabilitiesRequest;
+import org.elasticsearch.action.fieldcaps.FieldCapabilitiesResponse;
+import org.elasticsearch.client.Client;
+import org.elasticsearch.common.Strings;
+import org.elasticsearch.index.query.TermQueryBuilder;
+import org.elasticsearch.search.aggregations.Aggregation;
+import org.elasticsearch.search.aggregations.AggregationBuilders;
+import org.elasticsearch.search.aggregations.AggregatorFactories;
+import org.elasticsearch.search.aggregations.metrics.Percentile;
+import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.test.client.NoOpClient;
+import org.elasticsearch.xpack.core.transform.transforms.pivot.AggregationConfig;
+import org.elasticsearch.xpack.core.transform.transforms.pivot.GroupConfig;
+import org.elasticsearch.xpack.core.transform.transforms.pivot.GroupConfigTests;
+import org.elasticsearch.xpack.core.transform.transforms.pivot.PivotConfig;
+import org.junit.After;
+import org.junit.Before;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.Consumer;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class AggregationSchemaAndResultTests extends ESTestCase {
+
+    private Client client;
+
+    @Before
+    public void setupClient() {
+        if (client != null) {
+            client.close();
+        }
+        client = new MyMockClient(getTestName());
+    }
+
+    @After
+    public void tearDownClient() {
+        client.close();
+    }
+
+    private class MyMockClient extends NoOpClient {
+
+        MyMockClient(String testName) {
+            super(testName);
+        }
+
+        @SuppressWarnings("unchecked")
+        @Override
+        protected <Request extends ActionRequest, Response extends ActionResponse> void doExecute(
+            ActionType<Response> action,
+            Request request,
+            ActionListener<Response> listener
+        ) {
+
+            if (request instanceof FieldCapabilitiesRequest) {
+                FieldCapabilitiesRequest fieldCapsRequest = (FieldCapabilitiesRequest) request;
+
+                Map<String, Map<String, FieldCapabilities>> fieldCaps = new HashMap<>();
+                for (String field : fieldCapsRequest.fields()) {
+
+                    // expect a field name like "double_field" where type is a prefix
+                    String[] nameTypePair = Strings.split(field, "_");
+                    String type = nameTypePair != null ? nameTypePair[0] : "long";
+
+                    fieldCaps.put(
+                        field,
+                        Collections.singletonMap(
+                            type,
+                            new FieldCapabilities(field, type, true, true, null, null, null, Collections.emptyMap())
+                        )
+                    );
+                }
+
+                // FieldCapabilitiesResponse is package private, thats why we use a mock
+                FieldCapabilitiesResponse response = mock(FieldCapabilitiesResponse.class);
+                when(response.get()).thenReturn(fieldCaps);
+
+                for (String field : fieldCaps.keySet()) {
+                    when(response.getField(field)).thenReturn(fieldCaps.get(field));
+                }
+
+                listener.onResponse((Response) response);
+                return;
+            }
+
+            super.doExecute(action, request, listener);
+        }
+    }
+
+    public void testBasic() throws InterruptedException {
+        AggregatorFactories.Builder aggs = new AggregatorFactories.Builder();
+
+        // aggs which produce 1 output
+        aggs.addAggregator(AggregationBuilders.avg("avg_rating").field("long_stars"));
+        aggs.addAggregator(AggregationBuilders.max("max_rating").field("long_stars"));
+        aggs.addAggregator(AggregationBuilders.count("count_rating").field("keyword_group"));
+        aggs.addAggregator(AggregationBuilders.min("min_something").field("float_something"));
+
+        // percentile produces 1 output per percentile + 1 for the parent object
+        aggs.addAggregator(AggregationBuilders.percentiles("p_rating").field("long_stars").percentiles(1, 5, 10, 50, 99.9));
+
+        // scripted metric produces no output because its dynamic
+        aggs.addAggregator(AggregationBuilders.scriptedMetric("collapsed_ratings"));
+
+        AggregationConfig aggregationConfig = new AggregationConfig(Collections.emptyMap(), aggs);
+        GroupConfig groupConfig = GroupConfigTests.randomGroupConfig();
+        PivotConfig pivotConfig = new PivotConfig(groupConfig, aggregationConfig, null);
+
+        this.<Map<String, String>>assertAsync(
+            listener -> SchemaUtil.deduceMappings(client, pivotConfig, new String[] { "source-index" }, listener),
+            mappings -> {
+                assertEquals(groupConfig.getGroups().size() + 10, mappings.size());
+                assertEquals("long", mappings.get("max_rating"));
+                assertEquals("double", mappings.get("avg_rating"));
+                assertEquals("long", mappings.get("count_rating"));
+                assertEquals("float", mappings.get("min_something"));
+                assertEquals("object", mappings.get("p_rating"));
+                assertEquals("double", mappings.get("p_rating.1"));
+                assertEquals("double", mappings.get("p_rating.5"));
+                assertEquals("double", mappings.get("p_rating.10"));
+                assertEquals("double", mappings.get("p_rating.99_9"));
+
+                Aggregation agg = AggregationResultUtilsTests.createSingleMetricAgg("avg_rating", 33.3, "33.3");
+                assertThat(AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""), equalTo(33.3));
+
+                agg = AggregationResultUtilsTests.createPercentilesAgg(
+                    "p_agg",
+                    Arrays.asList(new Percentile(1, 0), new Percentile(50, 1.2), new Percentile(99, 2.4), new Percentile(99.5, 4.3))
+                );
+                assertThat(
+                    AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""),
+                    equalTo(asMap("1", 0.0, "50", 1.2, "99", 2.4, "99_5", 4.3))
+                );
+            }
+        );
+    }
+
+    public void testNested() throws InterruptedException {
+        AggregatorFactories.Builder aggs = new AggregatorFactories.Builder();
+        aggs.addAggregator(AggregationBuilders.filter("filter_1", new TermQueryBuilder("favorite_drink", "slurm")));
+        aggs.addAggregator(
+            AggregationBuilders.filter("filter_2", new TermQueryBuilder("species", "amphibiosan"))
+                .subAggregation(AggregationBuilders.max("max_drinks_2").field("long_drinks"))
+        );
+        aggs.addAggregator(
+            AggregationBuilders.filter("filter_3", new TermQueryBuilder("spaceship", "nimbus"))
+                .subAggregation(
+                    AggregationBuilders.filter("filter_3_1", new TermQueryBuilder("species", "amphibiosan"))
+                        .subAggregation(AggregationBuilders.max("max_drinks_3").field("float_drinks"))
+                )
+        );
+        aggs.addAggregator(
+            AggregationBuilders.filter("filter_4", new TermQueryBuilder("organization", "doop"))
+                .subAggregation(
+                    AggregationBuilders.filter("filter_4_1", new TermQueryBuilder("spaceship", "nimbus"))
+                        .subAggregation(
+                            AggregationBuilders.filter("filter_4_1_1", new TermQueryBuilder("species", "amphibiosan"))
+                                .subAggregation(AggregationBuilders.max("max_drinks_4").field("float_drinks"))
+                        )
+                        .subAggregation(
+                            AggregationBuilders.filter("filter_4_1_2", new TermQueryBuilder("species", "mutant"))
+                                .subAggregation(AggregationBuilders.max("min_drinks_4").field("double_drinks"))
+                        )
+                )
+        );
+
+        AggregationConfig aggregationConfig = new AggregationConfig(Collections.emptyMap(), aggs);
+        GroupConfig groupConfig = GroupConfigTests.randomGroupConfig();
+        PivotConfig pivotConfig = new PivotConfig(groupConfig, aggregationConfig, null);
+
+        this.<Map<String, String>>assertAsync(
+            listener -> SchemaUtil.deduceMappings(client, pivotConfig, new String[] { "source-index" }, listener),
+            mappings -> {
+                assertEquals(groupConfig.getGroups().size() + 12, mappings.size());
+                assertEquals("long", mappings.get("filter_1"));
+                assertEquals("object", mappings.get("filter_2"));
+                assertEquals("long", mappings.get("filter_2.max_drinks_2"));
+                assertEquals("object", mappings.get("filter_3"));
+                assertEquals("object", mappings.get("filter_3.filter_3_1"));
+                assertEquals("float", mappings.get("filter_3.filter_3_1.max_drinks_3"));
+                assertEquals("object", mappings.get("filter_4"));
+                assertEquals("object", mappings.get("filter_4.filter_4_1"));
+                assertEquals("object", mappings.get("filter_4.filter_4_1.filter_4_1_1"));
+                assertEquals("float", mappings.get("filter_4.filter_4_1.filter_4_1_1.max_drinks_4"));
+                assertEquals("object", mappings.get("filter_4.filter_4_1.filter_4_1_2"));
+                assertEquals("double", mappings.get("filter_4.filter_4_1.filter_4_1_2.min_drinks_4"));
+
+                Aggregation agg = AggregationResultUtilsTests.createSingleBucketAgg("filter_1", 36363);
+                assertThat(AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""), equalTo(36363L));
+
+                agg = AggregationResultUtilsTests.createSingleBucketAgg(
+                    "filter_2",
+                    23144,
+                    AggregationResultUtilsTests.createSingleMetricAgg("max_drinks_2", 45.0, "forty_five")
+                );
+                assertThat(AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""), equalTo(asMap("max_drinks_2", 45.0)));
+
+                agg = AggregationResultUtilsTests.createSingleBucketAgg(
+                    "filter_3",
+                    62426,
+                    AggregationResultUtilsTests.createSingleBucketAgg(
+                        "filter_3_1",
+                        33365,
+                        AggregationResultUtilsTests.createSingleMetricAgg("max_drinks_3", 35.0, "thirty_five")
+                    )
+                );
+                assertThat(
+                    AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""),
+                    equalTo(asMap("filter_3_1", asMap("max_drinks_3", 35.0)))
+                );
+
+                agg = AggregationResultUtilsTests.createSingleBucketAgg(
+                    "filter_4",
+                    62426,
+                    AggregationResultUtilsTests.createSingleBucketAgg(
+                        "filter_4_1",
+                        33365,
+                        AggregationResultUtilsTests.createSingleBucketAgg(
+                            "filter_4_1_1",
+                            12543,
+                            AggregationResultUtilsTests.createSingleMetricAgg("max_drinks_4", 1.0, "a small one")
+                        ),
+                        AggregationResultUtilsTests.createSingleBucketAgg(
+                            "filter_4_1_2",
+                            526,
+                            AggregationResultUtilsTests.createSingleMetricAgg("min_drinks_4", 7395.0, "a lot")
+                        )
+                    )
+                );
+                assertThat(
+                    AggregationResultUtils.getExtractor(agg).value(agg, mappings, ""),
+                    equalTo(
+                        asMap(
+                            "filter_4_1",
+                            asMap("filter_4_1_1", asMap("max_drinks_4", 1.0), "filter_4_1_2", asMap("min_drinks_4", 7395.0))
+                        )
+                    )
+                );
+            }
+        );
+    }
+
+    private <T> void assertAsync(Consumer<ActionListener<T>> function, Consumer<T> furtherTests) throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(1);
+        AtomicBoolean listenerCalled = new AtomicBoolean(false);
+
+        LatchedActionListener<T> listener = new LatchedActionListener<>(ActionListener.wrap(r -> {
+            assertTrue("listener called more than once", listenerCalled.compareAndSet(false, true));
+            furtherTests.accept(r);
+        }, e -> { fail("got unexpected exception: " + e); }), latch);
+
+        function.accept(listener);
+        assertTrue("timed out after 20s", latch.await(20, TimeUnit.SECONDS));
+    }
+
+    static Map<String, Object> asMap(Object... fields) {
+        assert fields.length % 2 == 0;
+        final Map<String, Object> map = new HashMap<>();
+        for (int i = 0; i < fields.length; i += 2) {
+            String field = (String) fields[i];
+            map.put(field, fields[i + 1]);
+        }
+        return map;
+    }
+}

x-pack/plugin/transform/src/test/java/org/elasticsearch/xpack/transform/transforms/pivot/AggregationsTests.java

@@ -6,16 +6,23 @@
 
 package org.elasticsearch.xpack.transform.transforms.pivot;
 
+import org.elasticsearch.common.collect.Tuple;
 import org.elasticsearch.common.io.stream.NamedWriteableRegistry;
 import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.index.query.TermQueryBuilder;
 import org.elasticsearch.search.SearchModule;
 import org.elasticsearch.search.aggregations.AggregationBuilder;
+import org.elasticsearch.search.aggregations.bucket.filter.FilterAggregationBuilder;
 import org.elasticsearch.search.aggregations.matrix.MatrixAggregationPlugin;
+import org.elasticsearch.search.aggregations.metrics.MaxAggregationBuilder;
+import org.elasticsearch.search.aggregations.metrics.MinAggregationBuilder;
+import org.elasticsearch.search.aggregations.metrics.PercentilesAggregationBuilder;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.xpack.analytics.AnalyticsPlugin;
 
 import java.util.Arrays;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 public class AggregationsTests extends ESTestCase {
@@ -77,6 +84,14 @@ public class AggregationsTests extends ESTestCase {
         // percentile
         assertEquals("double", Aggregations.resolveTargetMapping("percentiles", null));
         assertEquals("double", Aggregations.resolveTargetMapping("percentiles", "int"));
+
+        // filter
+        assertEquals("long", Aggregations.resolveTargetMapping("filter", null));
+        assertEquals("long", Aggregations.resolveTargetMapping("filter", "long"));
+        assertEquals("long", Aggregations.resolveTargetMapping("filter", "double"));
+
+        // corner case: source type null
+        assertEquals(null, Aggregations.resolveTargetMapping("min", null));
     }
 
     public void testAggregationsVsTransforms() {
@@ -105,4 +120,101 @@ public class AggregationsTests extends ESTestCase {
             );
         }
     }
+
+    public void testGetAggregationOutputTypesPercentiles() {
+        AggregationBuilder percentialAggregationBuilder = new PercentilesAggregationBuilder("percentiles").percentiles(1.0, 5.0, 10.0);
+
+        Tuple<Map<String, String>, Map<String, String>> inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(
+            percentialAggregationBuilder
+        );
+        assertTrue(inputAndOutputTypes.v1().isEmpty());
+        Map<String, String> outputTypes = inputAndOutputTypes.v2();
+        assertEquals(3, outputTypes.size());
+        assertEquals("percentiles", outputTypes.get("percentiles.1"));
+        assertEquals("percentiles", outputTypes.get("percentiles.5"));
+        assertEquals("percentiles", outputTypes.get("percentiles.10"));
+
+        // note: using the constructor, omits validation, in reality this test might fail
+        percentialAggregationBuilder = new PercentilesAggregationBuilder("percentiles").percentiles(1.0, 5.0, 5.0, 10.0);
+
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(percentialAggregationBuilder);
+        assertTrue(inputAndOutputTypes.v1().isEmpty());
+        outputTypes = inputAndOutputTypes.v2();
+
+        assertEquals(3, outputTypes.size());
+        assertEquals("percentiles", outputTypes.get("percentiles.1"));
+        assertEquals("percentiles", outputTypes.get("percentiles.5"));
+        assertEquals("percentiles", outputTypes.get("percentiles.10"));
+    }
+
+    public void testGetAggregationOutputTypesSubAggregations() {
+
+        AggregationBuilder filterAggregationBuilder = new FilterAggregationBuilder("filter_1", new TermQueryBuilder("type", "cat"));
+        Tuple<Map<String, String>, Map<String, String>> inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(
+            filterAggregationBuilder
+        );
+        assertTrue(inputAndOutputTypes.v1().isEmpty());
+
+        Map<String, String> outputTypes = inputAndOutputTypes.v2();
+        assertEquals(1, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1"));
+
+        AggregationBuilder subFilterAggregationBuilder = new FilterAggregationBuilder("filter_2", new TermQueryBuilder("subtype", "siam"));
+        filterAggregationBuilder.subAggregation(subFilterAggregationBuilder);
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(filterAggregationBuilder);
+        assertTrue(inputAndOutputTypes.v1().isEmpty());
+
+        outputTypes = inputAndOutputTypes.v2();
+        assertEquals(1, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1.filter_2"));
+
+        filterAggregationBuilder.subAggregation(new MaxAggregationBuilder("max_2").field("max_field"));
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(filterAggregationBuilder);
+        assertEquals(1, inputAndOutputTypes.v1().size());
+        Map<String, String> inputTypes = inputAndOutputTypes.v1();
+        assertEquals("max_field", inputTypes.get("filter_1.max_2"));
+
+        outputTypes = inputAndOutputTypes.v2();
+        assertEquals(2, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1.filter_2"));
+        assertEquals("max", outputTypes.get("filter_1.max_2"));
+
+        subFilterAggregationBuilder.subAggregation(new FilterAggregationBuilder("filter_3", new TermQueryBuilder("color", "white")));
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(filterAggregationBuilder);
+        assertEquals(1, inputAndOutputTypes.v1().size());
+
+        outputTypes = inputAndOutputTypes.v2();
+        assertEquals(2, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1.filter_2.filter_3"));
+        assertEquals("max", outputTypes.get("filter_1.max_2"));
+
+        subFilterAggregationBuilder.subAggregation(new MinAggregationBuilder("min_3").field("min_field"));
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(filterAggregationBuilder);
+        assertEquals(2, inputAndOutputTypes.v1().size());
+        inputTypes = inputAndOutputTypes.v1();
+        assertEquals("max_field", inputTypes.get("filter_1.max_2"));
+        assertEquals("min_field", inputTypes.get("filter_1.filter_2.min_3"));
+
+        outputTypes = inputAndOutputTypes.v2();
+        assertEquals(3, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1.filter_2.filter_3"));
+        assertEquals("max", outputTypes.get("filter_1.max_2"));
+        assertEquals("min", outputTypes.get("filter_1.filter_2.min_3"));
+
+        subFilterAggregationBuilder.subAggregation(
+            new PercentilesAggregationBuilder("percentiles").percentiles(33.3, 44.4, 88.8, 99.5)
+        );
+        inputAndOutputTypes = Aggregations.getAggregationInputAndOutputTypes(filterAggregationBuilder);
+        assertEquals(2, inputAndOutputTypes.v1().size());
+
+        outputTypes = inputAndOutputTypes.v2();
+        assertEquals(7, outputTypes.size());
+        assertEquals("filter", outputTypes.get("filter_1.filter_2.filter_3"));
+        assertEquals("max", outputTypes.get("filter_1.max_2"));
+        assertEquals("min", outputTypes.get("filter_1.filter_2.min_3"));
+        assertEquals("percentiles", outputTypes.get("filter_1.filter_2.percentiles.33_3"));
+        assertEquals("percentiles", outputTypes.get("filter_1.filter_2.percentiles.44_4"));
+        assertEquals("percentiles", outputTypes.get("filter_1.filter_2.percentiles.88_8"));
+        assertEquals("percentiles", outputTypes.get("filter_1.filter_2.percentiles.99_5"));
+    }
 }

x-pack/plugin/transform/src/test/java/org/elasticsearch/xpack/transform/transforms/pivot/PivotTests.java

@@ -215,8 +215,8 @@ public class PivotTests extends ESTestCase {
                 "{\"pivot_scripted_metric\": {\n"
                     + "\"scripted_metric\": {\n"
                     + "    \"init_script\" : \"state.transactions = []\",\n"
-                    + "    \"map_script\" : \"state.transactions.add("
-                    + "doc.type.value == 'sale' ? doc.amount.value : -1 * doc.amount.value)\",\n"
+                    + "    \"map_script\" : "
+                    + "        \"state.transactions.add(doc.type.value == 'sale' ? doc.amount.value : -1 * doc.amount.value)\", \n"
                     + "    \"combine_script\" : \"double profit = 0; for (t in state.transactions) { profit += t } return profit\",\n"
                     + "    \"reduce_script\" : \"double profit = 0; for (a in states) { profit += a } return profit\"\n"
                     + "  }\n"
@@ -251,6 +251,12 @@ public class PivotTests extends ESTestCase {
                     + "}"
             );
         }
+        if (agg.equals(AggregationType.FILTER.getName())) {
+            return parseAggregations(
+                "{" + "\"pivot_filter\": {" + "  \"filter\": {" + "   \"term\": {\"field\": \"value\"}" + "  }" + "}" + "}"
+            );
+        }
+
         return parseAggregations(
             "{\n" + "  \"pivot_" + agg + "\": {\n" + "    \"" + agg + "\": {\n" + "      \"field\": \"values\"\n" + "    }\n" + "  }" + "}"
         );