来自于 stackoverflow Elasticsearch Mapping - Rename existing field

You could do this by creating an Ingest pipeline, that contains a Rename Processor in combination with the Reindex API.

PUT _ingest/pipeline/my_rename_pipeline
{
  "description" : "describe pipeline",
  "processors" : [
    {
      "rename": {
        "field": "fieldCamelcase",
        "target_field": "fieldCamelCase"
      }
    }
  ]
}

POST _reindex
{
  "source": {
    "index": "source"
  },
  "dest": {
    "index": "dest",
    "pipeline": "my_rename_pipeline"
  }
} 

这种操作，会新建一个index，并不是直接在原来的索引的基础上进行直接修改字段名。

而且在最终执行时候，会有这种问题

{
  "took": 1170,
  "timed_out": false,
  "total": 111500,
  "updated": 0,
  "created": 971,
  "deleted": 0,
  "batches": 1,
  "version_conflicts": 0,
  "noops": 0,
  "retries": {
    "bulk": 0,
    "search": 0
  },
  "throttled_millis": 0,
  "requests_per_second": -1,
  "throttled_until_millis": 0,
  "failures": [
    {
      "index": "case-info-new-test",
      "type": "case_info",
      "id": "5beae7d0264f4b001bea7d46",
      "cause": {
        "type": "exception",
        "reason": "java.lang.IllegalArgumentException: java.lang.IllegalArgumentException: field [case_owner_id] doesn't exist",
        "caused_by": {
          "type": "illegal_argument_exception",
          "reason": "java.lang.IllegalArgumentException: field [case_owner_id] doesn't exist",
          "caused_by": {
            "type": "illegal_argument_exception",
            "reason": "field [case_owner_id] doesn't exist"
          }
        },
        "header": {
          "processor_type": "rename"
        }
      },
      "status": 500
    },
    {
      "index": "case-info-new-test",
      "type": "case_info",
      "id": "5beaa0125c94560014527e92",
      "cause": {
        "type": "exception",
        "reason": "java.lang.IllegalArgumentException: java.lang.IllegalArgumentException: field [case_owner_id] doesn't exist",
        "caused_by": {
          "type": "illegal_argument_exception",
          "reason": "java.lang.IllegalArgumentException: field [case_owner_id] doesn't exist",
          "caused_by": {
            "type": "illegal_argument_exception",
            "reason": "field [case_owner_id] doesn't exist"
          }
        },
        "header": {
          "processor_type": "rename"
        }
      },
      "status": 500
    }
  ]
}