Check field data type before casting when applying geo distance sort

docs/changelog/130924.yaml

@@ -0,0 +1,6 @@
+pr: 130924
+summary: Check field data type before casting when applying geo distance sort
+area: Search
+type: bug
+issues:
+ - 129500

server/src/main/java/org/elasticsearch/search/sort/GeoDistanceSortBuilder.java

@@ -599,7 +599,13 @@ private IndexGeoPointFieldData fieldData(SearchExecutionContext context) {
                 throw new IllegalArgumentException("failed to find mapper for [" + fieldName + "] for geo distance based sort");
             }
         }
-        return context.getForField(fieldType, MappedFieldType.FielddataOperation.SEARCH);
+        IndexFieldData<?> indexFieldData = context.getForField(fieldType, MappedFieldType.FielddataOperation.SEARCH);
+        if (indexFieldData instanceof IndexGeoPointFieldData) {
+            return (IndexGeoPointFieldData) indexFieldData;
+        }
+        throw new IllegalArgumentException(
+            "unable to apply geo distance sort to field [" + fieldName + "] of type [" + fieldType.typeName() + "]"
+        );
     }
 
     private Nested nested(SearchExecutionContext context) throws IOException {

server/src/test/java/org/elasticsearch/search/sort/GeoDistanceSortBuilderTests.java

@@ -23,6 +23,7 @@
 import org.elasticsearch.index.mapper.GeoPointFieldMapper;
 import org.elasticsearch.index.mapper.MappedFieldType;
 import org.elasticsearch.index.mapper.NestedPathFieldMapper;
+import org.elasticsearch.index.mapper.NumberFieldMapper;
 import org.elasticsearch.index.query.GeoValidationMethod;
 import org.elasticsearch.index.query.MatchAllQueryBuilder;
 import org.elasticsearch.index.query.MatchNoneQueryBuilder;
@@ -99,6 +100,9 @@ public static GeoDistanceSortBuilder randomGeoDistanceSortBuilder() {
 
     @Override
     protected MappedFieldType provideMappedFieldType(String name) {
+        if (name.equals("double")) {
+            return new NumberFieldMapper.NumberFieldType(name, NumberFieldMapper.NumberType.DOUBLE);
+        }
         return new GeoPointFieldMapper.GeoPointFieldType(name);
     }
 
@@ -531,6 +535,12 @@ public void testBuildInvalidPoints() throws IOException {
             );
             assertEquals("illegal longitude value [-360.0] for [GeoDistanceSort] for field [fieldName].", ex.getMessage());
         }
+        {
+            GeoDistanceSortBuilder sortBuilder = new GeoDistanceSortBuilder("double", 0.0, 180.0);
+            sortBuilder.validation(GeoValidationMethod.STRICT);
+            IllegalArgumentException ex = expectThrows(IllegalArgumentException.class, () -> sortBuilder.build(searchExecutionContext));
+            assertEquals("unable to apply geo distance sort to field [double] of type [double]", ex.getMessage());
+        }
     }
 
     /**