Painless null pointer exception

[biggiesmallsAG]

Document:

      {
        "_index": "optik",
        "_type": "indicators",
        "_id": "AVwPUXjQo8Mgt9lhybim",
        "_score": 1,
        "_routing": "test1",
        "_parent": "test1",
        "_source": {
          "indicators_list": [
            {
              "indicator": "apple.com.au",
              "ptag_type": "",
              "ptag_analyst": "",
              "ptag_date": "1970-01-01T00:00:00.000000"
            }
          ]
        }
      }

Scripting:

POST optik/indicators/AVwPUXjQo8Mgt9lhybim/_update?parent=test1
{
  "script": {
    "lang": "painless",
    "inline": "int i=0; for (i = 0; i < doc['indicators_list'].length; i++) { if (doc['indicators_list'][i]['indicator'].value == 'apple.com.au') { doc['indicators_list'][i]['ptag_type'].value = params.ptag_type;}}",
    "params": {
      "ptag_type": "malicious"
    }
  }
}

Error:

{
  "error": {
    "root_cause": [
      {
        "type": "remote_transport_exception",
        "reason": "[h4M67tk][10.37.129.11:9300][indices:data/write/update[s]]"
      }
    ],
    "type": "illegal_argument_exception",
    "reason": "failed to execute script",
    "caused_by": {
      "type": "script_exception",
      "reason": "compile error",
      "script_stack": [],
      "script": "int i=0; for (i = 0; i < doc['indicators_list'].length; i++) { if (doc['indicators_list'][i]['indicator'].value == 'apple.com.au') { doc['indicators_list'][i]['ptag_type'].value = params.ptag_type;}}",
      "lang": "painless",
      "caused_by": {
        "type": "null_pointer_exception",
        "reason": null
      }
    }
  },
  "status": 400
}

Im at a dead end, would be nice to know where the null pointer is.. or why my script that is seemingly syntactically correct is failing..

[rjernst]

There are two problems here. First, accessing a field within a doc must use the full field path. Ie, doc is not a map of maps, so if you have a doc containing { "a": { "b": "value"} } you must use doc['a.b'].value. Second, nested fields are not supported within scripts (these are different documents in lucene, so cannot be accessed by the parent document).

relates #23719

[biggiesmallsAG]

Hi,
Ok, for my usecase, how do i iterate an object via a script to update the doc without overriding (or doing it manually in my python backend? My indicators_list array will always be nested (full of indicators).

[rjernst]

@biggiesmallsAG Github is reserved for feature requests and confirmed bug reports. Please ask questions on our forum.

[nik9000]

I think this is actually a bug:

      "script_stack": [],

If there is an error we need to point you to where the error is.

[biggiesmallsAG]

agreed, at least a stack trace would be able to point to @rjernst explanation of nested fields not being supported.

[madguy02]

@rjernst sorry to mention you directly in the thread , but i am still wondering why does iterating a nested array of objects using

for (int i=0;i<ctx._source.files.length;i++) {
 Debug.explain(ctx._source.files[i])
}

throws null pointer exception
Does elastic support this yet or i am going wrong somewhere

Note :

This is on ES 6.7. Here files field is a nested field with multiple properties