Fix downsampling with disabled subobjects

docs/changelog/138715.yaml

@@ -0,0 +1,5 @@
+pr: 138715
+summary: Fix downsampling with disabled subobjects
+area: Downsampling
+type: bug
+issues: []

server/src/main/java/org/elasticsearch/action/admin/cluster/stats/MappingVisitor.java

@@ -9,10 +9,16 @@
 
 package org.elasticsearch.action.admin.cluster.stats;
 
+import org.elasticsearch.common.TriConsumer;
+
+import java.util.HashMap;
 import java.util.Map;
 import java.util.function.BiConsumer;
 
 public final class MappingVisitor {
+    public static final String PROPERTIES = "properties";
+    public static final String FIELD_TYPE = "type";
+    public static final String MULTI_FIELDS = "fields";
 
     private MappingVisitor() {}
 
@@ -25,7 +31,7 @@ private static void visitMapping(
         final String path,
         final BiConsumer<String, Map<String, ?>> fieldMappingConsumer
     ) {
-        Object properties = mapping.get("properties");
+        Object properties = mapping.get(PROPERTIES);
         if (properties instanceof Map) {
             @SuppressWarnings("unchecked")
             Map<String, ?> propertiesAsMap = (Map<String, ?>) properties;
@@ -40,7 +46,7 @@ private static void visitMapping(
                     visitMapping(fieldMapping, prefix + ".", fieldMappingConsumer);
 
                     // Multi fields
-                    Object fieldsO = fieldMapping.get("fields");
+                    Object fieldsO = fieldMapping.get(MULTI_FIELDS);
                     if (fieldsO instanceof Map) {
                         @SuppressWarnings("unchecked")
                         Map<String, ?> fields = (Map<String, ?>) fieldsO;
@@ -75,4 +81,67 @@ public static void visitRuntimeMapping(Map<String, ?> mapping, BiConsumer<String
             runtimeFieldMappingConsumer.accept(entry.getKey(), runtimeFieldMapping);
         }
     }
+
+    /**
+     * This visitor traverses the source mapping and copies the structure to the destination mapping after applying
+     * the fieldMappingConsumer to the individual field mappings.
+     */
+    public static void visitAndCopyMapping(
+        final Map<String, ?> sourceMapping,
+        final Map<String, Object> destMapping,
+        final TriConsumer<String, Map<String, ?>, Map<String, Object>> fieldMappingConsumer
+    ) {
+        Map<String, ?> sourceProperties = getMapOrNull(sourceMapping.get(PROPERTIES));
+        if (sourceProperties == null) {
+            return;
+        }
+        Map<String, Object> destProperties = new HashMap<>(sourceProperties.size());
+        destMapping.put(PROPERTIES, destProperties);
+
+        for (Map.Entry<String, ?> entry : sourceProperties.entrySet()) {
+            Map<String, ?> sourceFieldMapping = getMapOrNull(entry.getValue());
+            if (sourceFieldMapping == null) {
+                return;
+            }
+            var destFieldMapping = processAndCopy(entry.getKey(), sourceFieldMapping, destProperties, fieldMappingConsumer);
+            visitAndCopyMapping(sourceFieldMapping, destFieldMapping, fieldMappingConsumer);
+
+            // Multi fields
+            Map<String, ?> sourceMultiFields = getMapOrNull(sourceFieldMapping.get(MULTI_FIELDS));
+            if (sourceMultiFields == null) {
+                continue;
+            }
+            Map<String, Object> destFields = new HashMap<>(sourceMultiFields.size());
+            destFieldMapping.put(MULTI_FIELDS, destFields);
+            for (Map.Entry<String, ?> multiFieldEntry : sourceMultiFields.entrySet()) {
+                String multiFieldName = multiFieldEntry.getKey();
+                Map<String, ?> sourceMultiFieldMapping = getMapOrNull(multiFieldEntry.getValue());
+                if (sourceMultiFieldMapping == null) {
+                    continue;
+                }
+                processAndCopy(multiFieldName, sourceMultiFieldMapping, destFields, fieldMappingConsumer);
+            }
+        }
+    }
+
+    private static Map<String, ?> getMapOrNull(Object object) {
+        if (object instanceof Map) {
+            @SuppressWarnings("unchecked")
+            Map<String, ?> map = (Map<String, ?>) object;
+            return map;
+        }
+        return null;
+    }
+
+    private static Map<String, Object> processAndCopy(
+        String fieldName,
+        Map<String, ?> sourceFieldMapping,
+        Map<String, Object> destParentMap,
+        TriConsumer<String, Map<String, ?>, Map<String, Object>> fieldMappingConsumer
+    ) {
+        Map<String, Object> destFieldMapping = new HashMap<>(sourceFieldMapping.size());
+        destParentMap.put(fieldName, destFieldMapping);
+        fieldMappingConsumer.apply(fieldName, sourceFieldMapping, destFieldMapping);
+        return destFieldMapping;
+    }
 }

server/src/test/java/org/elasticsearch/action/admin/cluster/stats/MappingVisitorTests.java

@@ -136,4 +136,61 @@ public void testCountRuntimeFields() {
     private static void collectRuntimeTypes(Map<String, ?> mapping, Set<String> types) {
         MappingVisitor.visitRuntimeMapping(mapping, (f, m) -> types.add(m.get("type").toString()));
     }
+
+    @SuppressWarnings("unchecked")
+    public void testConvertLongToKeyword() {
+        Map<String, Object> longType = Map.of("type", "long");
+        Map<String, Object> textType = Map.of("type", "text");
+        Map<String, Object> floatType = Map.of("type", "float", "scaling_factor", 1000);
+        Map<String, Object> multiField = Map.of("type", "keyword", "fields", Map.of("my-long", longType, "my-float", floatType));
+        Map<String, Object> objectField = Map.of("type", "object", "properties", Map.of("my-text", textType, "my-long", longType));
+        Map<String, Object> expectedProperties = Map.of(
+            "properties",
+            Map.of("my-long", longType, "my-float", floatType, "my-multi-field", multiField, "my-object", objectField)
+        );
+
+        HashMap<String, Object> result = new HashMap<>();
+        MappingVisitor.visitAndCopyMapping(expectedProperties, result, (ignored, source, dest) -> {
+            for (String key : source.keySet()) {
+                if (key.equals("type") && source.get(key).equals("long")) {
+                    dest.put(key, "keyword");
+                } else {
+                    dest.put(key, source.get(key));
+                }
+            }
+        });
+
+        assertTrue(result.containsKey("properties"));
+        Map<String, Object> properties = (Map<String, Object>) result.get("properties");
+
+        assertTrue(properties.containsKey("my-long"));
+        Map<String, Object> myLong = (Map<String, Object>) properties.get("my-long");
+        assertEquals("keyword", myLong.get("type"));
+
+        assertTrue(properties.containsKey("my-float"));
+        Map<String, Object> myFloat = (Map<String, Object>) properties.get("my-float");
+        assertEquals("float", myFloat.get("type"));
+        assertEquals(1000, myFloat.get("scaling_factor"));
+
+        assertTrue(properties.containsKey("my-multi-field"));
+        Map<String, Object> myMultiField = (Map<String, Object>) properties.get("my-multi-field");
+        assertEquals("keyword", myMultiField.get("type"));
+        assertTrue(myMultiField.containsKey("fields"));
+        Map<String, Object> foundFields = (Map<String, Object>) myMultiField.get("fields");
+        assertTrue(foundFields.containsKey("my-long"));
+        assertEquals("keyword", ((Map<String, Object>) foundFields.get("my-long")).get("type"));
+        assertTrue(foundFields.containsKey("my-float"));
+        assertEquals("float", ((Map<String, Object>) foundFields.get("my-float")).get("type"));
+        assertEquals(1000, ((Map<String, Object>) foundFields.get("my-float")).get("scaling_factor"));
+
+        assertTrue(properties.containsKey("my-object"));
+        Map<String, Object> myObject = (Map<String, Object>) properties.get("my-object");
+        assertEquals("object", myObject.get("type"));
+        assertTrue(myObject.containsKey("properties"));
+        Map<String, Object> foundSubObjects = (Map<String, Object>) myObject.get("properties");
+        assertTrue(foundSubObjects.containsKey("my-long"));
+        assertEquals("keyword", ((Map<String, Object>) foundSubObjects.get("my-long")).get("type"));
+        assertTrue(foundSubObjects.containsKey("my-text"));
+        assertEquals("text", ((Map<String, Object>) foundSubObjects.get("my-text")).get("type"));
+    }
 }

x-pack/plugin/downsample/src/internalClusterTest/java/org/elasticsearch/xpack/downsample/DownsampleIT.java

@@ -102,6 +102,14 @@ public void testDownsamplingPassthroughMetrics() throws Exception {
                     "cpu_usage": {
                         "type": "double",
                         "time_series_metric": "counter"
+                    },
+                    "memory_usage": {
+                        "type": "double",
+                        "time_series_metric": "counter"
+                    },
+                    "memory_usage.free": {
+                        "type": "double",
+                        "time_series_metric": "counter"
                     }
                   }
                 }
@@ -120,6 +128,8 @@ public void testDownsamplingPassthroughMetrics() throws Exception {
                     .field("attributes.os.name", randomFrom("linux", "windows", "macos"))
                     .field("metrics.cpu_usage", randomDouble())
                     .field("metrics.memory_usage", randomDouble())
+                    .field("metrics.memory_usage.free", randomDouble())
+                    .field("metrics.load", randomDouble())
                     .endObject();
             } catch (IOException e) {
                 throw new RuntimeException(e);

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/FieldValueFetcher.java

@@ -103,10 +103,7 @@ static List<FieldValueFetcher> create(SearchExecutionContext context, String[] f
                     } else {
                         fieldData = context.getForField(fieldType, MappedFieldType.FielddataOperation.SEARCH);
                     }
-                    final String fieldName = context.isMultiField(field)
-                        ? fieldType.name().substring(0, fieldType.name().lastIndexOf('.'))
-                        : fieldType.name();
-                    fetchers.add(new FieldValueFetcher(fieldName, fieldType, fieldData, samplingMethod));
+                    fetchers.add(new FieldValueFetcher(fieldType.name(), fieldType, fieldData, samplingMethod));
                 }
             }
         }

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/TimeseriesFieldTypeHelper.java

@@ -52,7 +52,7 @@ public boolean isTimeSeriesDimension(final String unused, final Map<String, ?> f
         return Boolean.TRUE.equals(fieldMapping.get(TIME_SERIES_DIMENSION_PARAM)) && isPassthroughField(fieldMapping) == false;
     }
 
-    public static boolean isPassthroughField(final Map<String, ?> fieldMapping) {
+    public boolean isPassthroughField(final Map<String, ?> fieldMapping) {
         return PassThroughObjectMapper.CONTENT_TYPE.equals(fieldMapping.get(ContextMapping.FIELD_TYPE));
     }