fieldValueFactorSearch.go

func fieldValueFactorSearch(index, Type, searchTerm, category, animated string) []Result {
  
	client, _ := elastic.NewSimpleClient(elastic.SetURL("http://13.232.108.38:8000"),
		elastic.SetErrorLog(log.New(os.Stderr, "ELASTIC ", log.LstdFlags)),
		elastic.SetInfoLog(log.New(os.Stdout, "", log.LstdFlags)))
  
	ctx := context.Background()
  
  var Results []Sticker

	fieldFactor := elastic.NewFieldValueFactorFunction().Field("votes").Modifier("log1p")

	query := elastic.NewBoolQuery()

	if searchTerm != "" {
		query = query.Must(elastic.NewTermQuery("tags", searchTerm))
	}

	if animated != "" {
		query = query.Filter(elastic.NewTermQuery("animated", animated))
	}

	if category != "" {
		query = query.Filter(elastic.NewTermQuery("category", category))
	}

	functionScore := elastic.NewFunctionScoreQuery().Query(query).AddScoreFunc(fieldFactor)

	src, _ := functionScore.Source()
	data, _ := json.Marshal(src)

	searchResult, err := client.Search().
		Index(index).
		Type(Type).
		Query(elastic.NewRawStringQuery(string(data))).
		From(0).Size(100).
		Do(ctx)

	if err != nil {
    panic(err)
	}
  
  if searchResult.Hits.TotalHits > 0 {
		fmt.Printf("Found a total of %d Stickers in Exact Search\n", searchResult.Hits.TotalHits)

		// Iterate through results
		for _, hit := range searchResult.Hits.Hits {
			// hit.Index contains the name of the index

			// Deserialize hit.Source into a Tweet (could also be just a map[string]interface{}).
			var t Sticker
			err := json.Unmarshal(*hit.Source, &t)
			if err != nil {
				fmt.Println("Deserialization failed")
			}
      
      Results = append(Results, t)
    }
  }
  
  if len(result) == 0 {
		fmt.Println("No results found")
	}
  
  return Results

}