Custom score on the basis of a field value(colon separated) and boosting factor in ES 6.2.4

[amit.nema]

custom score on the basis of a field value(colon separated) and booting factor

e.g I have a indexed a field as
scorevector : "Lucene:1.3 Hadoop:4.3 Elastic:6.8 Lucene:7.2"

I would like to search the index as

my_index/_search
get_custom_score : {
scorevector : "Lucene^5 Hadoop^2 Elastic^3 HDFS^1.5"
}

score must be returned as [(1.3+7.2)/2]*5 + 4.3*2 + 6.8*3 = 50.25
term "Lucene" payload average [(1.3+7.2)/2]

I tried few things as below

POST my_index
{
"settings": {
"analysis": {
"analyzer": {
"payloads": {
"type": "custom",
"tokenizer": "whitespace",
"filter": [
"my_delimited_payload"
]
}
},
"filter": {
"my_delimited_payload": {
"type": "delimited_payload",
"delimiter": ":",
"encoding": "float"
}
}
}
},
"mappings": {
"_doc": {
"properties": {
"scorevector": {
"norms": true,
"index": true,
"store": false,
"type": "text",
"analyzer": "payloads"
}
}
}
}
}

PUT my_index
{scorevector : "Lucene:1.3 Hadoop:4.3 Elastic:6.8 HDFS:7.2"}

Now as per my understanding this payload (float value next to colon) should be analyzed.

I think I can make use of AveragePayloadFunction.

I need some solution to get the score as needed.

Could you please help me to with some example code?

Any help will be appreacciated.

Thanks in advance
Amit

[amit.nema]

I could resolve it by making two plugins as below

• MySimilarityPlugin.java : extends Plugin
  @Override
  public void onIndexModule(IndexModule im) {
      im.addSimilarity(..., new MySimilarity(...))
  }
  MySimilarity extends ClassicSimilarity and all method returns as 1.

• MyQueryParserPlugin.java : extends Plugin implements SearchPlugin

1. Override getQueries(..MyQueryBuilder...)
2. MyQueryBuilder is same as QueryStringQueryBuilder use MyQueryParser instead QueryStringQueryParser.
3. MyQueryParser extends QueryStringQueryParser
   @Override
   public Query getFieldQuery(String f, String qt, boolean q) {
       return new PayloadScoreQuery(new SpanTermQuery(new Term(field, queryText)), new AveragePayloadFunction());
   }

• 'test' index as below
  curl -XPUT 'localhost:9200/test' -d ' {
  "settings": {
  "index": {
  "similarity": {
  "mysim": {
  "type": "mysimilarity"
  }
  },
  "analysis": {
  "analyzer": {
  "myanalyzer": {
  "filter": [
  "mytokenfilter"
  ],
  "type": "custom",
  "tokenizer": "whitespace"
  }
  },
  "filter": {
  "mytokenfilter": {
  "type": "delimited_payload",
  "delimiter": ":"
  }
  }
  }
  }
  },
  "mapping": {
  "docs": {
  "properties": {
  "mytext": {
  "type": "text",
  "similarity": "mysim",
  "analyzer": "myanalyzer"
  }
  }
  }
  }
  }'

Its working as expected.

Please let me know, if you have any better approach.