---
prelude: >
    In Elasticsearch 2.x field names cannot contain '.', so when indexing
    document with property contains '.' in field name, it will fail with
    error "cannot contain '.'".
upgrade:
  - If you want to search field contains '.', you need to replace '.' with
    '++', e.g. 'sahara_tag_2.7.1' -> 'sahara_tag_2++7++1'.
fixes:
  - Replace '.' with '++' when saving documents to Elasticsearch, and
    convert back when searching results.
