This meta ticket tracks the changes in Elasticsearch 7.8.0 that require changes in the client:

New APIs

• Cluster Delete VotingConfigExclusions
• Cluster Post VotingConfigExclusions

Cluster Coordination

• Voting config exclusions should work with absent nodes #50836 (issue: #47990)

Infra/Core

• Deprecate node local storage setting #54374

New features

Aggregations

• Add support for filters to T-Test aggregation #54980 (issue: #53692)
• Add Student's t-test aggregation support #54469 (issue: #53692)

Features/Indices APIs

• [ ] Add simulate template composition API _index_template/_simulate_index/{name} #55686 (issue: #53101) Simulate index template APIs are experimental

Geo

• Add new point field. #53804

Enhancements

Aggregations

• Expose agg usage in Feature Usage API #55732 (issue: #53746)

Analysis

• Add preserve_original setting in ngram token filter #55432

Cluster Coordination

• Add voting config exclusion add and clear API spec and integration test cases #55760 (issue: #48131)

Features/CAT APIs

• [ ] Add support for V2 index templates to /_cat/templates #55829 (issue: #53101) v2 index template APIs are experimental

Features/Indices APIs

• [ ] Update template v2 api rest spec #55948 (issue: #53101) v2 index template APIs are experimental
• [ ] Add prefer_v2_templates flag and index setting #55411 (issue: #53101) v2 index template APIs are experimental

Features/Stats

• [ ] Add Bulk stats track the bulk per shard #52208 (issues: #47345, #50536) Doesn't look to be in 7.8. See Add Bulk stats track the bulk per shard elasticsearch#52208 (comment)

Geo

• Doc values support for geo shapes. [ISSUE] #37206. NEST already implements doc_values for GeoShapeProperty

Infra/REST API

• [ ] Add validation to the usage service #54617 no client changes required

Infra/Scripting

• Scripting: stats per context in nodes stats #54008 (issue: #50152)

MULTIPLE AREA LABELS

• Add geo_shape mapper supporting doc-values in Spatial Plugin #55037 (issue: #53562)
• [ ] Add pre-configured “lowercase” normalizer #53882 (issue: #53872) No client changes required

Snapshot/Restore

• [ ] Allow Deleting Multiple Snapshots at Once #55474 Change has been made to REST spec in master (Update snapshot.delete.json to make snapshot a list type elasticsearch#57326), but change will not be ported to 7.x

Transform

• [Transform] add throttling #56007 (issue: #54862)

Bug fixes

Aggregations

• Add analytics plugin usage stats to _xpack/usage #54911 (issue: #54847)

Analysis

• Add preserve_original setting in edge ngram token filter #55766 (issue: #55767)

Features/Ingest

• Fix empty_value handling in CsvProcessor #55649 (issue: #55643)