Disallow "enabled" attribute change for types in mapping update (#33933)

This commit adds a check for "enabled" attribute change for types when
a RestPutMappingAction is received. A MappingException is thrown when
such a change is detected.  Change are prevented in both ways: "false -> true" 
and "true -> false".

Closes #33566

server/src/main/java/org/elasticsearch/index/mapper/ObjectMapper.java

@@ -458,6 +458,8 @@ public class ObjectMapper extends Mapper implements Cloneable {
 
         for (Mapper mergeWithMapper : mergeWith) {
             Mapper mergeIntoMapper = mappers.get(mergeWithMapper.simpleName());
+            checkEnabledFieldChange(mergeWith, mergeWithMapper, mergeIntoMapper);
+
             Mapper merged;
             if (mergeIntoMapper == null) {
                 // no mapping, simply add it
@@ -470,6 +472,18 @@ public class ObjectMapper extends Mapper implements Cloneable {
         }
     }
 
+    private static void checkEnabledFieldChange(ObjectMapper mergeWith, Mapper mergeWithMapper, Mapper mergeIntoMapper) {
+        if (mergeIntoMapper instanceof ObjectMapper && mergeWithMapper instanceof ObjectMapper) {
+            final ObjectMapper mergeIntoObjectMapper = (ObjectMapper) mergeIntoMapper;
+            final ObjectMapper mergeWithObjectMapper = (ObjectMapper) mergeWithMapper;
+
+            if (mergeIntoObjectMapper.isEnabled() != mergeWithObjectMapper.isEnabled()) {
+                final String path = mergeWith.fullPath() + "." + mergeWithObjectMapper.simpleName() + ".enabled";
+                throw new MapperException("Can't update attribute for type [" + path + "] in index mapping");
+            }
+        }
+    }
+
     @Override
     public ObjectMapper updateFieldType(Map<String, MappedFieldType> fullNameToFieldType) {
         List<Mapper> updatedMappers = null;

server/src/test/java/org/elasticsearch/index/mapper/ObjectMapperMergeTests.java

@@ -0,0 +1,125 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.elasticsearch.index.mapper;
+
+import com.google.common.collect.ImmutableMap;
+import org.elasticsearch.Version;
+import org.elasticsearch.common.settings.Settings;
+import org.elasticsearch.index.mapper.FieldMapper.CopyTo;
+import org.elasticsearch.index.mapper.FieldMapper.MultiFields;
+import org.elasticsearch.index.mapper.TextFieldMapper.TextFieldType;
+import org.elasticsearch.test.ESTestCase;
+import org.junit.AfterClass;
+
+import java.util.Map;
+
+import static java.util.Collections.emptyMap;
+import static org.elasticsearch.cluster.metadata.IndexMetaData.SETTING_VERSION_CREATED;
+import static org.hamcrest.Matchers.notNullValue;
+
+public class ObjectMapperMergeTests extends ESTestCase {
+
+    private static FieldMapper barFieldMapper = createTextFieldMapper("bar");
+    private static FieldMapper bazFieldMapper = createTextFieldMapper("baz");
+
+    private static RootObjectMapper rootObjectMapper = createRootObjectMapper(
+        "type1", true, ImmutableMap.of(
+            "disabled", createObjectMapper("disabled", false, emptyMap()),
+            "foo", createObjectMapper("foo", true, ImmutableMap.of(
+                "bar", barFieldMapper))));
+
+    @AfterClass
+    public static void cleanupReferences() {
+        barFieldMapper = null;
+        bazFieldMapper = null;
+        rootObjectMapper = null;
+    }
+
+    public void testMerge() {
+        // GIVEN an enriched mapping with "baz" new field
+        ObjectMapper mergeWith = createRootObjectMapper(
+            "type1", true, ImmutableMap.of(
+                "disabled", createObjectMapper("disabled", false, emptyMap()),
+                "foo", createObjectMapper("foo", true, ImmutableMap.of(
+                    "bar", barFieldMapper,
+                    "baz", bazFieldMapper))));
+
+        // WHEN merging mappings
+        final ObjectMapper merged = rootObjectMapper.merge(mergeWith);
+
+        // THEN "baz" new field is added to merged mapping
+        final ObjectMapper mergedFoo = (ObjectMapper) merged.getMapper("foo");
+        assertThat(mergedFoo.getMapper("bar"), notNullValue());
+        assertThat(mergedFoo.getMapper("baz"), notNullValue());
+    }
+
+    public void testMergeWhenDisablingField() {
+        // GIVEN a mapping with "foo" field disabled
+        ObjectMapper mergeWith = createRootObjectMapper(
+            "type1", true, ImmutableMap.of(
+                "disabled", createObjectMapper("disabled", false, emptyMap()),
+                "foo", createObjectMapper("foo", false, emptyMap())));
+
+        // WHEN merging mappings
+        // THEN a MapperException is thrown with an excepted message
+        MapperException e = expectThrows(MapperException.class, () -> rootObjectMapper.merge(mergeWith));
+        assertEquals("Can't update attribute for type [type1.foo.enabled] in index mapping", e.getMessage());
+    }
+
+    public void testMergeWhenEnablingField() {
+        // GIVEN a mapping with "disabled" field enabled
+        ObjectMapper mergeWith = createRootObjectMapper(
+            "type1", true, ImmutableMap.of(
+                "disabled", createObjectMapper("disabled", true, emptyMap()),
+                "foo", createObjectMapper("foo", true, ImmutableMap.of(
+                    "bar", barFieldMapper))));
+
+        // WHEN merging mappings
+        // THEN a MapperException is thrown with an excepted message
+        MapperException e = expectThrows(MapperException.class, () -> rootObjectMapper.merge(mergeWith));
+        assertEquals("Can't update attribute for type [type1.disabled.enabled] in index mapping", e.getMessage());
+    }
+
+    private static RootObjectMapper createRootObjectMapper(String name, boolean enabled, Map<String, Mapper> mappers) {
+        final Settings indexSettings = Settings.builder().put(SETTING_VERSION_CREATED, Version.CURRENT).build();
+        final Mapper.BuilderContext context = new Mapper.BuilderContext(indexSettings, new ContentPath());
+        final RootObjectMapper rootObjectMapper = new RootObjectMapper.Builder(name).enabled(enabled).build(context);
+
+        mappers.values().forEach(rootObjectMapper::putMapper);
+
+        return rootObjectMapper;
+    }
+
+    private static ObjectMapper createObjectMapper(String name, boolean enabled, Map<String, Mapper> mappers) {
+        final Settings indexSettings = Settings.builder().put(SETTING_VERSION_CREATED, Version.CURRENT).build();
+        final Mapper.BuilderContext context = new Mapper.BuilderContext(indexSettings, new ContentPath());
+        final ObjectMapper mapper = new ObjectMapper.Builder(name).enabled(enabled).build(context);
+
+        mappers.values().forEach(mapper::putMapper);
+
+        return mapper;
+    }
+
+    private static TextFieldMapper createTextFieldMapper(String name) {
+        final TextFieldType fieldType = new TextFieldType();
+        final Settings indexSettings = Settings.builder().put(SETTING_VERSION_CREATED, Version.CURRENT).build();
+
+        return new TextFieldMapper(name, fieldType, fieldType, -1, null, indexSettings, MultiFields.empty(), CopyTo.empty());
+    }
+}