update after review

Author: drempapis

server/src/internalClusterTest/java/org/elasticsearch/action/IndicesRequestIT.java

@@ -68,6 +68,7 @@
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.common.util.concurrent.ThreadContext;
 import org.elasticsearch.index.mapper.DocumentParsingException;
+import org.elasticsearch.index.mapper.MapperService;
 import org.elasticsearch.index.query.QueryBuilders;
 import org.elasticsearch.indices.TestIndexNameExpressionResolver;
 import org.elasticsearch.plugins.NetworkPlugin;
@@ -590,7 +591,11 @@ public void testRejectDocumentWithTooManyArrayObjectFields() throws Exception {
         String indexName = "array-limit-test";
         int arrayLimit = 10;
 
-        assertAcked(prepareCreate(indexName).setSettings(Settings.builder().put("index.mapping.nested_objects.limit", arrayLimit).build()));
+        assertAcked(
+            prepareCreate(indexName).setSettings(
+                Settings.builder().put(MapperService.INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING.getKey(), arrayLimit).build()
+            )
+        );
 
         try (XContentBuilder doc = XContentFactory.jsonBuilder()) {
             doc.startObject();
@@ -607,7 +612,7 @@ public void testRejectDocumentWithTooManyArrayObjectFields() throws Exception {
 
             assertThat(
                 e.getMessage(),
-                containsString("The number of nested documents has exceeded " + "the allowed limit of [" + arrayLimit + "]")
+                containsString("The number of array objects has exceeded " + "the allowed limit of [" + arrayLimit + "]")
             );
         }
     }

server/src/main/java/org/elasticsearch/common/settings/IndexScopedSettings.java

@@ -167,6 +167,7 @@ public final class IndexScopedSettings extends AbstractScopedSettings {
                 Store.INDEX_STORE_STATS_REFRESH_INTERVAL_SETTING,
                 MapperService.INDEX_MAPPING_NESTED_FIELDS_LIMIT_SETTING,
                 MapperService.INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING,
+                MapperService.INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING,
                 MapperService.INDEX_MAPPING_IGNORE_DYNAMIC_BEYOND_LIMIT_SETTING,
                 MapperService.INDEX_MAPPING_TOTAL_FIELDS_LIMIT_SETTING,
                 MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING,

server/src/main/java/org/elasticsearch/index/IndexSettings.java

@@ -48,6 +48,7 @@
 
 import static org.elasticsearch.cluster.metadata.IndexMetadata.SETTING_INDEX_VERSION_CREATED;
 import static org.elasticsearch.cluster.routing.allocation.ExistingShardsAllocator.EXISTING_SHARDS_ALLOCATOR_SETTING;
+import static org.elasticsearch.index.mapper.MapperService.INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING;
 import static org.elasticsearch.index.mapper.MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING;
 import static org.elasticsearch.index.mapper.MapperService.INDEX_MAPPING_DIMENSION_FIELDS_LIMIT_SETTING;
 import static org.elasticsearch.index.mapper.MapperService.INDEX_MAPPING_FIELD_NAME_LENGTH_LIMIT_SETTING;
@@ -925,6 +926,7 @@ private void setRetentionLeaseMillis(final TimeValue retentionLease) {
     private volatile String requiredPipeline;
     private volatile long mappingNestedFieldsLimit;
     private volatile long mappingNestedDocsLimit;
+    private volatile long mappingArrayObjectsLimit;
     private volatile long mappingTotalFieldsLimit;
     private volatile boolean ignoreDynamicFieldsBeyondLimit;
     private volatile long mappingDepthLimit;
@@ -1100,6 +1102,7 @@ public IndexSettings(final IndexMetadata indexMetadata, final Settings nodeSetti
         defaultPipeline = scopedSettings.get(DEFAULT_PIPELINE);
         mappingNestedFieldsLimit = scopedSettings.get(INDEX_MAPPING_NESTED_FIELDS_LIMIT_SETTING);
         mappingNestedDocsLimit = scopedSettings.get(INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING);
+        mappingArrayObjectsLimit = scopedSettings.get(INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING);
         mappingTotalFieldsLimit = scopedSettings.get(INDEX_MAPPING_TOTAL_FIELDS_LIMIT_SETTING);
         ignoreDynamicFieldsBeyondLimit = scopedSettings.get(INDEX_MAPPING_IGNORE_DYNAMIC_BEYOND_LIMIT_SETTING);
         mappingDepthLimit = scopedSettings.get(INDEX_MAPPING_DEPTH_LIMIT_SETTING);
@@ -1215,6 +1218,7 @@ public IndexSettings(final IndexMetadata indexMetadata, final Settings nodeSetti
         scopedSettings.addSettingsUpdateConsumer(INDEX_SOFT_DELETES_RETENTION_LEASE_PERIOD_SETTING, this::setRetentionLeaseMillis);
         scopedSettings.addSettingsUpdateConsumer(INDEX_MAPPING_NESTED_FIELDS_LIMIT_SETTING, this::setMappingNestedFieldsLimit);
         scopedSettings.addSettingsUpdateConsumer(INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING, this::setMappingNestedDocsLimit);
+        scopedSettings.addSettingsUpdateConsumer(INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING, this::setMappingArrayObjectsLimit);
         scopedSettings.addSettingsUpdateConsumer(
             INDEX_MAPPING_IGNORE_DYNAMIC_BEYOND_LIMIT_SETTING,
             this::setIgnoreDynamicFieldsBeyondLimit
@@ -1754,6 +1758,14 @@ private void setMappingNestedDocsLimit(long value) {
         this.mappingNestedDocsLimit = value;
     }
 
+    public long getMappingArrayObjectsLimit() {
+        return mappingArrayObjectsLimit;
+    }
+
+    private void setMappingArrayObjectsLimit(long value) {
+        this.mappingArrayObjectsLimit = value;
+    }
+
     public long getMappingTotalFieldsLimit() {
         return mappingTotalFieldsLimit;
     }

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

@@ -750,16 +750,16 @@ private static void parseNonDynamicArray(
         XContentParser.Token previousToken = parser.currentToken();
         int elements = 0;
         int countArray = 0;
-        long nestedDocsLimit = context.indexSettings().getMappingNestedDocsLimit();
+        long arrayObjectsLimit = context.indexSettings().getMappingArrayObjectsLimit();
         while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
             if (token == XContentParser.Token.START_OBJECT) {
-                if (countArray++ >= nestedDocsLimit) {
+                if (countArray++ >= arrayObjectsLimit) {
                     throw new IllegalStateException(
-                        "The number of nested documents has exceeded the allowed limit of ["
-                            + nestedDocsLimit
+                        "The number of array objects has exceeded the allowed limit of ["
+                            + arrayObjectsLimit
                             + "]. "
                             + "This limit can be set by changing the ["
-                            + MapperService.INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING.getKey()
+                            + MapperService.INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING.getKey()
                             + "] index level setting."
                     );
                 }

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

@@ -116,6 +116,15 @@ public boolean isAutoUpdate() {
         Property.Dynamic,
         Property.IndexScope
     );
+    // maximum allowed number of objects for an array field in a document
+    public static final Setting<Long> INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING = Setting.longSetting(
+        "index.mapping.array_objects.limit",
+        20000L,
+        0,
+        Property.Dynamic,
+        Property.IndexScope
+    );
+
     public static final Setting<Long> INDEX_MAPPING_TOTAL_FIELDS_LIMIT_SETTING = Setting.longSetting(
         "index.mapping.total_fields.limit",
         1000L,

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

@@ -905,7 +905,7 @@ public void testLimitNestedDocs() throws Exception {
         SourceToParse source2 = new SourceToParse("2", BytesReference.bytes(docBuilder2), XContentType.JSON);
         DocumentParsingException e = expectThrows(DocumentParsingException.class, () -> docMapper.parse(source2));
         assertEquals(
-            "[1:73] failed to parse: The number of nested documents has exceeded the allowed limit of ["
+            "[1:73] The number of nested documents has exceeded the allowed limit of ["
                 + maxNoNestedDocs
                 + "]. This limit can be set by changing the ["
                 + MapperService.INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING.getKey()

x-pack/plugin/ccr/src/test/java/org/elasticsearch/xpack/ccr/action/TransportResumeFollowActionTests.java

@@ -322,6 +322,7 @@ public void testDynamicIndexSettingsAreClassified() {
         replicatedSettings.add(MapperService.INDEX_MAPPING_TOTAL_FIELDS_LIMIT_SETTING);
         replicatedSettings.add(MapperService.INDEX_MAPPING_IGNORE_DYNAMIC_BEYOND_LIMIT_SETTING);
         replicatedSettings.add(MapperService.INDEX_MAPPING_NESTED_DOCS_LIMIT_SETTING);
+        replicatedSettings.add(MapperService.INDEX_MAPPING_ARRAY_OBJECTS_LIMIT_SETTING);
         replicatedSettings.add(MapperService.INDEX_MAPPING_NESTED_FIELDS_LIMIT_SETTING);
         replicatedSettings.add(MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING);
         replicatedSettings.add(MapperService.INDEX_MAPPING_FIELD_NAME_LENGTH_LIMIT_SETTING);