From 93b04fb7bd9731b806de297650e734cc923727d7 Mon Sep 17 00:00:00 2001
From: Jim Ferenczi <jim.ferenczi@elastic.co>
Date: Mon, 24 Jul 2017 13:07:19 +0200
Subject: [PATCH] The default _parent field should not try to load global
 ordinals (#25851)

The default _parent field tries to load global ordinals because it is created with eager_global_ordinals=true.
This leads to an IllegalStateException because this field does not have doc_values.
This change explicitely sets eager_global_ordinals to false in order to avoid the ISE on startup.

Fixes #25849
---
 .../org/elasticsearch/index/mapper/ParentFieldMapper.java     | 4 +++-
 .../elasticsearch/index/mapper/ParentFieldMapperTests.java    | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/org/elasticsearch/index/mapper/ParentFieldMapper.java b/core/src/main/java/org/elasticsearch/index/mapper/ParentFieldMapper.java
index 482935437ed..f984871fbed 100644
--- a/core/src/main/java/org/elasticsearch/index/mapper/ParentFieldMapper.java
+++ b/core/src/main/java/org/elasticsearch/index/mapper/ParentFieldMapper.java
@@ -65,7 +65,7 @@ public class ParentFieldMapper extends MetadataFieldMapper {
             FIELD_TYPE.setIndexOptions(IndexOptions.NONE);
             FIELD_TYPE.setHasDocValues(true);
             FIELD_TYPE.setDocValuesType(DocValuesType.SORTED);
-            FIELD_TYPE.setEagerGlobalOrdinals(true);
+            FIELD_TYPE.setEagerGlobalOrdinals(false);
             FIELD_TYPE.freeze();
         }
     }
@@ -78,6 +78,8 @@ public class ParentFieldMapper extends MetadataFieldMapper {
 
         public Builder(String documentType) {
             super(Defaults.NAME, new ParentFieldType(Defaults.FIELD_TYPE, documentType), Defaults.FIELD_TYPE);
+            // Defaults to true
+            eagerGlobalOrdinals(true);
             this.documentType = documentType;
             builder = this;
         }
diff --git a/core/src/test/java/org/elasticsearch/index/mapper/ParentFieldMapperTests.java b/core/src/test/java/org/elasticsearch/index/mapper/ParentFieldMapperTests.java
index 935562a2bc4..d7d94786938 100644
--- a/core/src/test/java/org/elasticsearch/index/mapper/ParentFieldMapperTests.java
+++ b/core/src/test/java/org/elasticsearch/index/mapper/ParentFieldMapperTests.java
@@ -124,6 +124,8 @@ public class ParentFieldMapperTests extends ESSingleNodeTestCase {
         Set<String> allFields = new HashSet<>(mapperService.simpleMatchToIndexNames("*"));
         assertTrue(allFields.contains("_parent"));
         assertFalse(allFields.contains("_parent#null"));
+        MappedFieldType fieldType = mapperService.fullName("_parent");
+        assertFalse(fieldType.eagerGlobalOrdinals());
     }
 
     private static int getNumberOfFieldWithParentPrefix(ParseContext.Document doc) {