Key conflicts when field data service load two fields for different types but with same indexName

[coderplay]

Let's take a look at the implementation of IndexFieldDataService. getForField(FieldMapper<?> mapper)

    public <IFD extends IndexFieldData<?>> IFD getForField(FieldMapper<?> mapper) {
...
        final String key = fieldNames.indexName();
        IndexFieldData<?> fieldData = loadedFieldData.get(key);
...
                    fieldData = builder.build(index, indexSettings, mapper, cache, circuitBreakerService, indexService.mapperService());
                    loadedFieldData.put(fieldNames.indexName(), fieldData);
...
        return (IFD) fieldData;
    }

This method use FieldMapper's indexName as key, fetch field data for a concurrent HashMap. The indexName of FieldMapper is always from a DocumentMapper, which is built like this

// DocumentMapper.Builder
        public Builder(String index, Settings indexSettings, RootObjectMapper.Builder builder) {
...
            this.builderContext = new Mapper.BuilderContext(indexSettings, new ContentPath(1));
...
        }

The new ContentPath(1) will effect all FieldMapper's indexNames of a DocumentMapper. Those indexName won't get a full path with a qualifier.

Here is an FieldMapper example which passed into IndexFieldDataService. getForField(FieldMapper<?> mapper)

names = {org.elasticsearch.index.mapper.FieldMapper$Names@5182}
name = {java.lang.String@7248}"country"
indexName = {java.lang.String@7249}"country"
indexNameClean = {java.lang.String@7248}"country"
fullName = {java.lang.String@7250}"country"
sourcePath = {java.lang.String@7250}"country"

When two two fields for different types but with same indexName passed into IndexFieldDataService. getForField(FieldMapper<?> mapper), the second call will retrieve a wrong field data since its indexName will match the key from the first method call which will be already in loadedFieldData.

Please correct me if I misunderstand the logic of this part.

[clintongormley]

Hi @coderplay

You are correct. We are removing index_name (#6677) and requiring that fields of the same name in different types in the same index have the same mappings (#4081).

thanks