Can't perform exact k-NN with scoring script

Plugins k-NN
1

below is my opendistro installed version

{
  "name" : "node-xxxxx",
  "cluster_name" : "some-cluster-name",
  "cluster_uuid" : "asdlfldsjgldsjlas",
  "version" : {
    "number" : "7.8.0",
    "build_flavor" : "oss",
    "build_type" : "deb",
    "build_hash" : "757314695644ea9a1dc2fecd26d1a43856725e65",
    "build_date" : "2020-06-14T19:35:50.234439Z",
    "build_snapshot" : false,
    "lucene_version" : "8.5.1",
    "minimum_wire_compatibility_version" : "6.8.0",
    "minimum_index_compatibility_version" : "6.0.0-beta1"
  },
  "tagline" : "You Know, for Search"
}

I am strictly following this official example here

https://opendistro.github.io/for-elasticsearch-docs/docs/knn/knn-score-script/

to test the exact KNN.

but I get these error:

{
  "error" : {
    "root_cause" : [
      {
        "type" : "query_shard_exception",
        "reason" : "failed to create query: script_lang not supported [knn]",
        "index_uuid" : "qkhNyyiQRYChbuB3vgpHrw",
        "index" : "my-knn-index-1"
      }
    ],
    "type" : "search_phase_execution_exception",
    "reason" : "all shards failed",
    "phase" : "query",
    "grouped" : true,
    "failed_shards" : [
      {
        "shard" : 0,
        "index" : "my-knn-index-1",
        "node" : "AwdSnmJlRTG_8fdu6xXdkw",
        "reason" : {
          "type" : "query_shard_exception",
          "reason" : "failed to create query: script_lang not supported [knn]",
          "index_uuid" : "qkhNyyiQRYChbuB3vgpHrw",
          "index" : "my-knn-index-1",
          "caused_by" : {
            "type" : "illegal_argument_exception",
            "reason" : "script_lang not supported [knn]"
          }
        }
      }
    ]
  },
  "status" : 400
}

basically the error message says script_lang not supported [knn], but I have already installed knn plugin because my approximate KNN search works.

2

Hi @Lancerchiang

Script scoring is not available in ODFE 1.9. Script scoring was added in ODFE 1.11.

Jack