Add runtime_mappings to search request

This adds a way to specify the `runtime_mappings` on a search request
which are always "runtime" fields. It looks like:
```
curl -XDELETE -uelastic:password -HContent-Type:application/json localhost:9200/test
curl -XPOST -uelastic:password -HContent-Type:application/json 'localhost:9200/test/_bulk?pretty&refresh' -d'
{"index": {}}
{"animal": "cat", "sound": "meow"}
{"index": {}}
{"animal": "dog", "sound": "woof"}
{"index": {}}
{"animal": "snake", "sound": "hisssssssssssssssss"}
'

curl -XPOST -uelastic:password -HContent-Type:application/json localhost:9200/test/_search?pretty -d'
{
  "runtime_mappings": {
    "animal.upper": {
      "type": "keyword",
      "script": "for (String s : doc[\"animal.keyword\"]) {emit(s.toUpperCase())}"
    }
  },
  "query": {
    "match": {
      "animal.upper": "DOG"
    }
  }
}'
```

modules/analysis-common/src/test/java/org/elasticsearch/analysis/common/DisableGraphQueryTests.java

@@ -46,6 +46,7 @@
 import java.util.Collection;
 import java.util.Collections;
 
+import static java.util.Collections.emptyMap;
 import static org.hamcrest.Matchers.equalTo;
 
 /**
@@ -84,7 +85,7 @@ public void setup() {
         indexService = createIndex("test", settings, "t",
             "text_shingle", "type=text,analyzer=text_shingle",
             "text_shingle_unigram", "type=text,analyzer=text_shingle_unigram");
-        shardContext = indexService.newQueryShardContext(0, null, () -> 0L, null);
+        shardContext = indexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap());
 
         // parsed queries for "text_shingle_unigram:(foo bar baz)" with query parsers
         // that ignores position length attribute

modules/lang-painless/src/main/java/org/elasticsearch/painless/action/PainlessExecuteAction.java

@@ -85,6 +85,7 @@
 import java.util.Map;
 import java.util.Objects;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.action.ValidateActions.addValidationError;
 import static org.elasticsearch.rest.RestRequest.Method.GET;
 import static org.elasticsearch.rest.RestRequest.Method.POST;
@@ -555,7 +556,7 @@ private static Response prepareRamIndex(Request request,
                         searcher.setQueryCache(null);
                         final long absoluteStartMillis = System.currentTimeMillis();
                         QueryShardContext context =
-                            indexService.newQueryShardContext(0, searcher, () -> absoluteStartMillis, null);
+                            indexService.newQueryShardContext(0, searcher, () -> absoluteStartMillis, null, emptyMap());
                         return handler.apply(context, indexReader.leaves().get(0));
                     }
                 }

modules/lang-painless/src/test/java/org/elasticsearch/painless/NeedsScoreTests.java

@@ -32,6 +32,8 @@
 import java.util.List;
 import java.util.Map;
 
+import static java.util.Collections.emptyMap;
+
 /**
  * Test that needsScores() is reported correctly depending on whether _score is used
  */
@@ -45,7 +47,7 @@ public void testNeedsScores() {
         contexts.put(NumberSortScript.CONTEXT, Whitelist.BASE_WHITELISTS);
         PainlessScriptEngine service = new PainlessScriptEngine(Settings.EMPTY, contexts);
 
-        QueryShardContext shardContext = index.newQueryShardContext(0, null, () -> 0, null);
+        QueryShardContext shardContext = index.newQueryShardContext(0, null, () -> 0, null, emptyMap());
 
         NumberSortScript.Factory factory = service.compile(null, "1.2", NumberSortScript.CONTEXT, Collections.emptyMap());
         NumberSortScript.LeafFactory ss = factory.newFactory(Collections.emptyMap(), shardContext.lookup());

modules/percolator/src/test/java/org/elasticsearch/percolator/PercolatorFieldMapperTests.java

@@ -103,6 +103,7 @@
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.elasticsearch.index.query.QueryBuilders.boolQuery;
 import static org.elasticsearch.index.query.QueryBuilders.matchAllQuery;
@@ -515,7 +516,7 @@ public void testQueryWithRewrite() throws Exception {
         QueryShardContext shardContext = indexService.newQueryShardContext(
             randomInt(20), null, () -> {
                 throw new UnsupportedOperationException();
-            }, null);
+            }, null, emptyMap());
         PlainActionFuture<QueryBuilder> future = new PlainActionFuture<>();
         Rewriteable.rewriteAndFetch(queryBuilder, shardContext, future);
         assertQueryBuilder(qbSource, future.get());

modules/percolator/src/test/java/org/elasticsearch/percolator/PercolatorQuerySearchTests.java

@@ -51,6 +51,7 @@
 import java.util.Map;
 import java.util.function.Function;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.common.xcontent.XContentFactory.jsonBuilder;
 import static org.elasticsearch.index.query.QueryBuilders.boolQuery;
 import static org.elasticsearch.index.query.QueryBuilders.matchQuery;
@@ -258,7 +259,7 @@ public void testRangeQueriesWithNow() throws Exception {
         try (Engine.Searcher searcher = indexService.getShard(0).acquireSearcher("test")) {
             long[] currentTime = new long[] {System.currentTimeMillis()};
             QueryShardContext queryShardContext =
-                indexService.newQueryShardContext(0, searcher, () -> currentTime[0], null);
+                indexService.newQueryShardContext(0, searcher, () -> currentTime[0], null, emptyMap());
 
             BytesReference source = BytesReference.bytes(jsonBuilder().startObject()
                 .field("field1", "value")

server/src/main/java/org/elasticsearch/action/admin/indices/template/post/TransportSimulateIndexTemplateAction.java

@@ -56,6 +56,7 @@
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.cluster.metadata.MetadataIndexTemplateService.findConflictingV1Templates;
 import static org.elasticsearch.cluster.metadata.MetadataIndexTemplateService.findConflictingV2Templates;
 import static org.elasticsearch.cluster.metadata.MetadataIndexTemplateService.findV2Template;
@@ -182,7 +183,7 @@ public static Template resolveTemplate(final String matchingTemplate, final Stri
                 resolvedAliases, tempClusterState.metadata(), aliasValidator, xContentRegistry,
                 // the context is only used for validation so it's fine to pass fake values for the
                 // shard id and the current timestamp
-                tempIndexService.newQueryShardContext(0, null, () -> 0L, null)));
+                tempIndexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap())));
         Map<String, AliasMetadata> aliasesByName = aliases.stream().collect(
             Collectors.toMap(AliasMetadata::getAlias, Function.identity()));
 

server/src/main/java/org/elasticsearch/action/search/SearchRequest.java

@@ -42,6 +42,7 @@
 import java.util.Map;
 import java.util.Objects;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.action.ValidateActions.addValidationError;
 
 /**

server/src/main/java/org/elasticsearch/cluster/metadata/MetadataCreateIndexService.java

@@ -98,6 +98,7 @@
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
+import static java.util.Collections.emptyMap;
 import static java.util.stream.Collectors.toList;
 import static org.elasticsearch.cluster.metadata.IndexMetadata.INDEX_NUMBER_OF_REPLICAS_SETTING;
 import static org.elasticsearch.cluster.metadata.IndexMetadata.INDEX_NUMBER_OF_SHARDS_SETTING;
@@ -490,7 +491,7 @@ private ClusterState applyCreateIndexRequestWithV1Templates(final ClusterState c
                 MetadataIndexTemplateService.resolveAliases(templates), currentState.metadata(), aliasValidator,
                 // the context is only used for validation so it's fine to pass fake values for the
                 // shard id and the current timestamp
-                xContentRegistry, indexService.newQueryShardContext(0, null, () -> 0L, null)),
+                xContentRegistry, indexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap())),
             templates.stream().map(IndexTemplateMetadata::getName).collect(toList()), metadataTransformer);
     }
 
@@ -523,7 +524,7 @@ private ClusterState applyCreateIndexRequestWithV2Template(final ClusterState cu
                 MetadataIndexTemplateService.resolveAliases(currentState.metadata(), templateName), currentState.metadata(), aliasValidator,
                 // the context is only used for validation so it's fine to pass fake values for the
                 // shard id and the current timestamp
-                xContentRegistry, indexService.newQueryShardContext(0, null, () -> 0L, null)),
+                xContentRegistry, indexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap())),
             Collections.singletonList(templateName), metadataTransformer);
     }
 
@@ -569,7 +570,7 @@ private ClusterState applyCreateIndexRequestWithExistingMetadata(final ClusterSt
                 currentState.metadata(), aliasValidator, xContentRegistry,
                 // the context is only used for validation so it's fine to pass fake values for the
                 // shard id and the current timestamp
-                indexService.newQueryShardContext(0, null, () -> 0L, null)),
+                indexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap())),
             List.of(), metadataTransformer);
     }
 

server/src/main/java/org/elasticsearch/cluster/metadata/MetadataIndexAliasesService.java

@@ -47,6 +47,7 @@
 import java.util.function.Function;
 
 import static java.util.Collections.emptyList;
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.indices.cluster.IndicesClusterStateService.AllocatedIndices.IndexRemovalReason.NO_LONGER_ASSIGNED;
 
 /**
@@ -154,7 +155,7 @@ public ClusterState applyAliasActions(ClusterState currentState, Iterable<AliasA
                         // the context is only used for validation so it's fine to pass fake values for the shard id,
                         // but the current timestamp should be set to real value as we may use `now` in a filtered alias
                         aliasValidator.validateAliasFilter(alias, filter, indexService.newQueryShardContext(0, null,
-                            () -> System.currentTimeMillis(), null), xContentRegistry);
+                            () -> System.currentTimeMillis(), null, emptyMap()), xContentRegistry);
                     }
                 };
                 if (action.apply(newAliasValidator, metadata, index)) {

server/src/main/java/org/elasticsearch/cluster/metadata/MetadataIndexTemplateService.java

@@ -80,6 +80,7 @@
 import java.util.function.Predicate;
 import java.util.stream.Collectors;
 
+import static java.util.Collections.emptyMap;
 import static org.elasticsearch.cluster.metadata.MetadataCreateDataStreamService.validateTimestampFieldMapping;
 import static org.elasticsearch.indices.cluster.IndicesClusterStateService.AllocatedIndices.IndexRemovalReason.NO_LONGER_ASSIGNED;
 
@@ -1112,7 +1113,7 @@ private static void validateCompositeTemplate(final ClusterState state,
                     new AliasValidator(),
                     // the context is only used for validation so it's fine to pass fake values for the
                     // shard id and the current timestamp
-                    xContentRegistry, tempIndexService.newQueryShardContext(0, null, () -> 0L, null));
+                    xContentRegistry, tempIndexService.newQueryShardContext(0, null, () -> 0L, null, emptyMap()));
 
                 // triggers inclusion of _timestamp field and its validation:
                 String indexName = DataStream.BACKING_INDEX_PREFIX + temporaryIndexName;

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

@@ -192,7 +192,7 @@ public IndexService(
             assert indexAnalyzers != null;
             this.mapperService = new MapperService(indexSettings, indexAnalyzers, xContentRegistry, similarityService, mapperRegistry,
                 // we parse all percolator queries as they would be parsed on shard 0
-                () -> newQueryShardContext(0, null, System::currentTimeMillis, null), idFieldDataEnabled, scriptService);
+                () -> newQueryShardContext(0, null, System::currentTimeMillis, null, emptyMap()), idFieldDataEnabled, scriptService);
             this.indexFieldData = new IndexFieldDataService(indexSettings, indicesFieldDataCache, circuitBreakerService, mapperService);
             if (indexSettings.getIndexSortConfig().hasIndexSort()) {
                 // we delay the actual creation of the sort order for this index because the mapping has not been merged yet.
@@ -586,13 +586,19 @@ public IndexSettings getIndexSettings() {
      * Passing a {@code null} {@link IndexSearcher} will return a valid context, however it won't be able to make
      * {@link IndexReader}-specific optimizations, such as rewriting containing range queries.
      */
-    public QueryShardContext newQueryShardContext(int shardId, IndexSearcher searcher, LongSupplier nowInMillis, String clusterAlias) {
+    public QueryShardContext newQueryShardContext(
+        int shardId,
+        IndexSearcher searcher,
+        LongSupplier nowInMillis,
+        String clusterAlias,
+        Map<String, Object> runtimeMappings
+    ) {
         final SearchIndexNameMatcher indexNameMatcher =
             new SearchIndexNameMatcher(index().getName(), clusterAlias, clusterService, expressionResolver);
         return new QueryShardContext(
             shardId, indexSettings, bigArrays, indexCache.bitsetFilterCache(), indexFieldData::getForField, mapperService(),
             similarityService(), scriptService, xContentRegistry, namedWriteableRegistry, client, searcher, nowInMillis, clusterAlias,
-            indexNameMatcher, allowExpensiveQueries, valuesSourceRegistry);
+            indexNameMatcher, allowExpensiveQueries, valuesSourceRegistry, runtimeMappings);
     }
 
     /**