- [Go client docs](https://www.elastic.co/docs/reference/elasticsearch/clients/go/typed-api)
- [ES API docs](https://www.elastic.co/docs/api/doc/elasticsearch/operation/operation-indices-get)

- Fix index names custom completion
  https://github.com/urfave/cli/issues/2332
  https://github.com/urfave/cli/issues/2333

- index show: add more details, see screenshots

- add shard explain, aka:
  get /_cluster/allocation/explain {"index":"yourindex", "primary": true, "shard":0}


- add validate:

> GET /mock/_validate/query?rewrite=true {"from":0,"query":{"bool":{"must":[{"match_all":{}}]}},"size":20,"sort":[{"name":{"order":"desc"}}]}
{
  "valid": false
}

- add explain to search (maybe option -e)

> GET /mock/_explain/1780043878 {"query":{"bool":{"must":[{"match_all":{}}]}}}
{
  "_index": "mock",
  "_id": "1780043878",
  "matched": true,
  "explanation": {
    "value": 1.0,
    "description": "*:*",
    "details": []
  }
}