This section discusses the changes that you need to be aware of when migrating your application to Elasticsearch 6.6.

See also Release Highlights and Release Notes.

API changesedit

Machine learning API changesedit

The get jobs API and get job stats API can retrieve a maximum of 10,000 jobs. Likewise, the get datafeeds API and get datafeed stats API can retrieve a maximum of 10,000 datafeeds. Prior to version 6.6, there were no limits on the results from these APIs.

Watcher API changesedit

If you used the metric parameter with the stats API, the response contained incorrect labels, which are fixed in 6.6 and later releases. If you choose to retrieve queued_watches metrics, it now returns a queued_watches list instead of a current_watches list. Likewise, if you retrieve pending_watches metrics, it returns a current_watches list instead of a queued_watches list. The pending_watches metric is deprecated; use current_watches instead.

Search changesedit

query_string, multi_match and simple_query_string queryedit

Using automatically expanded fields for the "all fields" mode ("default_field": "*") for the query_string, multi_match and simple_query_string now raises a warning and a deprecation notice to be logged for queries beyond a certain number of fields. This limit will be enforced with a hard error starting in 7.0 and is determined by the indices.query.bool.max_clause_count setting which defaults to 1024.

Deprecate _source_exclude and _source_include URL Parametersedit

_source_exclude and _source_include are deprecated in favor of _source_excludes and _source_includes because those line up better with the rest of Elasticsearc’s APIs and Elasticsearch will raise a deprecation warning if those are used on any APIs. We plan to drop support for _source_exclude and _source_include in 7.0.

Deprecate boosts on inner span queries.edit

Setting boost on inner span queries is deprecated. In the next major version setting boost on inner span queries will throw a parsing exception.

Deprecate .values and .getValues() on doc values in scriptsedit

In scripts .values and .getValues() hasn’t been needed for a long, long time because the doc values objects themselves are Lists. So instead of:

GET /stackoverflow/_search
{
  "script_fields": {
    "tags_count": {
      "script" : {
        "source": "doc['tags'].values.size()"
      }
    }
  }
}

do

GET /stackoverflow/_search
{
  "script_fields": {
    "tags_count": {
      "script" : {
        "source": "doc['tags'].size()"
      }
    }
  }
}

Settings changesedit

Watcher notifications account settingsedit

The following settings have been deprecated and the secure variants should be used instead. The secure settings have to be defined inside each cluster node’s keystore, i.e., they are not to be specified via the cluster settings API.

Mappings changesedit

Changed default geo_shape indexing strategyedit

geo_shape types now default to using a vector indexing approach based on Lucene’s new LatLonShape field type. This indexes shapes as a triangular mesh instead of decomposing them into individual grid cells. To index using legacy prefix trees the tree parameter must be explicitly set to one of quadtree or geohash. Note that these strategies are now deprecated and will be removed in a future version.

The impact of changing the default indexing strategy is as follows:

IMPORTANT NOTE: If you are using any of the features listed above, newly created indexes with default geo_shape type (e.g., templates) might no longer work. It is recommended to update the geo_shape field mapping to explicitly define the tree parameter to one of geohash or quadtree. This will ensure newly created indexes are feature compatible with previously created indexes.

deprecated geo_shape parametersedit

The following type parameters are deprecated for the geo_shape field type: tree, precision, tree_levels, distance_error_pct, points_only, and strategy. They will be removed in a future version.