Check array size at parse time

[drempapis]

For an index having an array defined as nested

PUT /test-large-array
{
  "mappings": {
    "properties": {
      "array": {
        "type": "nested",           
        "properties": {
          "value": { "type": "integer" }
        }
      }
    }
  }
}

Indexing is protected by the index.mapping.nested_objects.limit setting, which restricts the number of nested objects allowed per document. However, in cases where an index is created via dynamic mapping without predefined limits, no adequate control is in place. This can result in the ingestion of a poison document—a document containing an array with a vast number of objects, which can severely degrade Elasticsearch cluster performance or even lead to node crashes due to excessive memory consumption and processing overhead.

This is a preliminary draft that attempts to address the scenario by incorporating safeguards, enforcement of the index.mapping.nested_objects.limit setting, and additional validation checks during document parsing. The approach aims to mitigate the risk of ingesting poison documents by interleaving structural controls and runtime validation to limit the number of objects.