No handler for type [join] declared on field

Question

I tried to create an index with join datatype on new AWS Elasticsearch 6.0.

Following instruction on Elasticsearch 6.0 document: https://www.elastic.co/guide/en/elasticsearch/reference/6.0/parent-join.html

PUT my_index
{
  "mappings": {
    "doc": {
      "properties": {
        "my_join_field": { 
          "type": "join",
          "relations": {
            "question": "answer" 
          }
        }
      }
    }
  }
}

Then I received the following error:

{
  "error": {
    "root_cause": [
      {
        "type": "mapper_parsing_exception",
        "reason": "No handler for type [join] declared on field [my_join_field]"
      }
    ],
    "type": "mapper_parsing_exception",
    "reason": "Failed to parse mapping [doc]: No handler for type [join] declared on field [my_join_field]",
    "caused_by": {
      "type": "mapper_parsing_exception",
      "reason": "No handler for type [join] declared on field [my_join_field]"
    }
  },
  "status": 400
}

I am wondering if I'm missing something? Thanks!

Answer 1

I got the same problem. Root cause is a missing module on the ElasticSearch service packaged by AWS. If you compare the configuration of a local installation and the one provided by AWS you will that this module is missing:

{
      "name" : "parent-join",
      "version" : "6.0.0",
      "description" : "This module adds the support parent-child queries and aggregations",
      "classname" : "org.elasticsearch.join.ParentJoinPlugin",
      "has_native_controller" : false,
      "requires_keystore" : false
}

Feature is now available in AWS ES 6.0