[Docs] Semantic field does not support object fields

[carlosdelest]

Clarify in docs that semantic_text fields are not currently supported in object fields

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[jimczi]

What's preventing the field to work inside object fields? We fail if the field is under a nested object but normal objects should work fine. We have tests for this.

[carlosdelest]

@jimczi

What's preventing the field to work inside object fields? We fail if the field is under a nested object but normal objects should work fine.

We're not overwriting correctly the object when calculating the inference. The following sequence:

PUT test_semantic

PUT /test_semantic/_mapping
{
  "properties": {
    "level_1": {
      "properties": {
        "level_2": {
          "type": "semantic_text",
          "inference_id": "elser-endpoint"
        }
      }
    }
  }
}

POST test_semantic/_doc/0001
{
  "level_1": {
    "level_2": "text"
  }
}

results in an error:

{
  "error": {
    "root_cause": [
      {
        "type": "document_parsing_exception",
        "reason": "[1:29] failed to parse field [level_1.level_2] of type [semantic_text] in document with id '0001'. Preview of field's value: 'null'"
      }
    ],
    "type": "document_parsing_exception",
    "reason": "[1:29] failed to parse field [level_1.level_2] of type [semantic_text] in document with id '0001'. Preview of field's value: 'null'",
    "caused_by": {
      "type": "illegal_argument_exception",
      "reason": "[1:29] [semantic_text] Expected START_OBJECT but was: END_OBJECT"
    }
  },
  "status": 400
}

I've been able to reproduce this locally.

We have tests for this.

We have tests for copy_to from object fields to (non-object) semantic fields here. I haven't found object tests on the inference tests.

[jimczi]

Oh that's a bug then! We should account for objects here?

[carlosdelest]

Oh that's a bug then! We should account for objects here?

👍 That is correct.

[jimczi]

We have tests here but they don't use the action filter.

[carlosdelest]

I'm closing this in favour of opening this GH bug