Fix range queries on _type field for singe type indices (#31756)

With the introduction of single types in 6.x, the `_type` field is no longer
indexed, which leads to certain queries that were working before throw errors
now. One such query is the `range` query, that, if performed on a single typer
index, currently throws an IAE since the field is not indexed.
This change adds special treatment for this case in the TypeFieldMapper,
comparing the range queries lower and upper bound to the one existing type and
either returns a MatchAllDocs or a MatchNoDocs query.

Relates to #31632
Closes #31476

Author: Christoph Büscher

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

@@ -35,6 +35,8 @@
 import org.apache.lucene.search.TermInSetQuery;
 import org.apache.lucene.search.TermQuery;
 import org.apache.lucene.util.BytesRef;
+import org.elasticsearch.common.logging.DeprecationLogger;
+import org.elasticsearch.common.logging.ESLoggerFactory;
 import org.elasticsearch.common.lucene.Lucene;
 import org.elasticsearch.common.lucene.search.Queries;
 import org.elasticsearch.common.xcontent.XContentBuilder;
@@ -90,6 +92,8 @@ public MetadataFieldMapper getDefault(MappedFieldType fieldType, ParserContext c
 
     static final class TypeFieldType extends StringFieldType {
 
+        private static final DeprecationLogger DEPRECATION_LOGGER = new DeprecationLogger(ESLoggerFactory.getLogger(TypeFieldType.class));
+
         TypeFieldType() {
         }
 
@@ -154,6 +158,29 @@ public Query termsQuery(List<?> values, QueryShardContext context) {
             }
         }
 
+        @Override
+        public Query rangeQuery(Object lowerTerm, Object upperTerm, boolean includeLower, boolean includeUpper, QueryShardContext context) {
+            DEPRECATION_LOGGER.deprecatedAndMaybeLog("range_single_type",
+                    "Running [range] query on [_type] field for an index with a single type. As types are deprecated, this functionality will be removed in future releases.");
+            Query result = new MatchAllDocsQuery();
+            String type = context.getMapperService().documentMapper().type();
+            if (type != null) {
+                BytesRef typeBytes = new BytesRef(type);
+                if (lowerTerm != null) {
+                    int comp = indexedValueForSearch(lowerTerm).compareTo(typeBytes);
+                    if (comp > 0 || (comp == 0 && includeLower == false)) {
+                        result = new MatchNoDocsQuery("[_type] was lexicographically smaller than lower bound of range");
+                    }
+                }
+                if (upperTerm != null) {
+                    int comp = indexedValueForSearch(upperTerm).compareTo(typeBytes);
+                    if (comp < 0 || (comp == 0 && includeUpper == false)) {
+                        result = new MatchNoDocsQuery("[_type] was lexicographically greater than upper bound of range");
+                    }
+                }
+            }
+            return result;
+        }
     }
 
     /**

server/src/test/java/org/elasticsearch/search/query/SearchQueryIT.java

@@ -1822,4 +1822,40 @@ public void testRangeQueryRangeFields_24744() throws Exception {
         SearchResponse searchResponse = client().prepareSearch("test").setQuery(range).get();
         assertHitCount(searchResponse, 1);
     }
+
+    public void testRangeQueryTypeField_31476() throws Exception {
+        assertAcked(prepareCreate("test").addMapping("foo", "field", "type=keyword"));
+
+        client().prepareIndex("test", "foo", "1").setSource("field", "value").get();
+        refresh();
+
+        RangeQueryBuilder range = new RangeQueryBuilder("_type").from("ape").to("zebra");
+        SearchResponse searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 1);
+
+        range = new RangeQueryBuilder("_type").from("monkey").to("zebra");
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 0);
+
+        range = new RangeQueryBuilder("_type").from("ape").to("donkey");
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 0);
+
+        range = new RangeQueryBuilder("_type").from("ape").to("foo").includeUpper(false);
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 0);
+
+        range = new RangeQueryBuilder("_type").from("ape").to("foo").includeUpper(true);
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 1);
+
+        range = new RangeQueryBuilder("_type").from("foo").to("zebra").includeLower(false);
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 0);
+
+        range = new RangeQueryBuilder("_type").from("foo").to("zebra").includeLower(true);
+        searchResponse = client().prepareSearch("test").setQuery(range).get();
+        assertHitCount(searchResponse, 1);
+    }
+
 }