@Override
public AggregatorFactory parse(
String aggregationName, XContentParser parser, SearchContext context) throws IOException {
String childType = null;
XContentParser.Token token;
String currentFieldName = null;
while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
if (token == XContentParser.Token.FIELD_NAME) {
currentFieldName = parser.currentName();
} else if (token == XContentParser.Token.VALUE_STRING) {
if ("type".equals(currentFieldName)) {
childType = parser.text();
} else {
throw new SearchParseException(
context,
"Unknown key for a "
+ token
+ " in ["
+ aggregationName
+ "]: ["
+ currentFieldName
+ "].");
}
} else {
throw new SearchParseException(
context, "Unexpected token " + token + " in [" + aggregationName + "].");
}
}
if (childType == null) {
throw new SearchParseException(
context, "Missing [child_type] field for children aggregation [" + aggregationName + "]");
}
DocumentMapper childDocMapper = context.mapperService().documentMapper(childType);
if (childDocMapper == null) {
throw new SearchParseException(
context, "[children] No mapping for for type [" + childType + "]");
}
ParentFieldMapper parentFieldMapper = childDocMapper.parentFieldMapper();
if (!parentFieldMapper.active()) {
throw new SearchParseException(context, "[children] _parent field not configured");
}
String parentType = parentFieldMapper.type();
DocumentMapper parentDocMapper = context.mapperService().documentMapper(parentType);
if (parentDocMapper == null) {
throw new SearchParseException(
context,
"[children] Type ["
+ childType
+ "] points to a non existent parent type ["
+ parentType
+ "]");
}
Filter parentFilter = context.filterCache().cache(parentDocMapper.typeFilter());
Filter childFilter = context.filterCache().cache(childDocMapper.typeFilter());
ParentChildIndexFieldData parentChildIndexFieldData =
context.fieldData().getForField(parentFieldMapper);
ValuesSourceConfig<ValuesSource.Bytes.WithOrdinals.ParentChild> config =
new ValuesSourceConfig<>(ValuesSource.Bytes.WithOrdinals.ParentChild.class);
config.fieldContext(
new FieldContext(
parentFieldMapper.names().indexName(), parentChildIndexFieldData, parentFieldMapper));
return new ParentToChildrenAggregator.Factory(
aggregationName, config, parentType, parentFilter, childFilter);
}
