Querying with Completion Suggesters in Elasticsearch with Java API

Question

I have my indices created, and mapping type for my 'suggest' field set to completion. I can't figure out how to configure the query for completion suggestions in elastic-search (Java API)

I'm trying to use this Query to base my implementation off of.

"song-suggest" : {
    "text" : "n",
    "completion" : {
        "field" : "suggest"
    }
}

Here's what I have so far,

CompletionSuggestionBuilder compBuilder = new CompletionSuggestionBuilder("complete"); 
compBuilder.text("n");
compBuilder.field("suggest");

SearchResponse searchResponse = localClient.prepareSearch(INDEX_NAME)
    .setTypes("completion")
    .setQuery(QueryBuilders.matchAllQuery())
    .addSuggestion(compBuilder)
    .execute().actionGet();

 CompletionSuggestion compSuggestion = searchResponse.getSuggest().getSuggestion("complete");

Am I missing something, doing something wrong? Thanks!

Answer 1

Not sure if this is the best thing to do. But this works for me. Hope it helps.

@Override
public List<SuggestionResponse> findSuggestionsFor(String suggestRequest) {
    CompletionSuggestionBuilder suggestionsBuilder = new CompletionSuggestionBuilder("completeMe");
    suggestionsBuilder.text(suggestRequest);
    suggestionsBuilder.field("suggest");
    SuggestRequestBuilder suggestRequestBuilder =
            client.prepareSuggest(MUSIC_INDEX).addSuggestion(suggestionsBuilder);

    logger.debug(suggestRequestBuilder.toString());

    SuggestResponse suggestResponse = suggestRequestBuilder.execute().actionGet();

    Iterator<? extends Suggest.Suggestion.Entry.Option> iterator =
            suggestResponse.getSuggest().getSuggestion("completeMe").iterator().next().getOptions().iterator();

    List<SuggestionResponse> items = new ArrayList<>();
    while (iterator.hasNext()) {
        Suggest.Suggestion.Entry.Option next = iterator.next();
        items.add(new SuggestionResponse(next.getText().string()));
    }
    return items;
}

Answer 2

paramsMap = req.getParameterMap();

String prefix = getParam("prefix");     

if (prefix == null) {
    EndpointUtil.badRequest("Autocomplete EndPoint: prefix parameter is missing", resp);
    return;
}

SearchRequest searchRequest;
SearchSourceBuilder searchSourceBuilder; 

searchRequest = new SearchRequest("section");
searchSourceBuilder = new SearchSourceBuilder();
searchSourceBuilder.timeout(new TimeValue(60, TimeUnit.SECONDS));
searchSourceBuilder.from(0);
searchSourceBuilder.size(MAX_HITS);     

CompletionSuggestionBuilder suggestionBuilder = new CompletionSuggestionBuilder("text.completion")
        .prefix(prefix, Fuzziness.AUTO).size(MAX_HITS);            

SuggestBuilder suggestBuilder  = new SuggestBuilder();

suggestBuilder.addSuggestion(SUGGEST_NAME, suggestionBuilder);

searchSourceBuilder.suggest(suggestBuilder);

searchRequest.source(searchSourceBuilder);      

SearchResponse searchResponse = getElasticClient().search(searchRequest);   

Suggest suggest = searchResponse.getSuggest();

List<Document> results = new ArrayList<Document>();     

  Suggest.Suggestion<Suggest.Suggestion.Entry<Suggest.Suggestion.Entry.Option>> suggestion 
    = suggest.getSuggestion(SUGGEST_NAME);

    List<Suggest.Suggestion.Entry<Suggest.Suggestion.Entry.Option>> list = suggestion.getEntries();
    for(Suggest.Suggestion.Entry<Suggest.Suggestion.Entry.Option> entry :list) {
        List<Suggest.Suggestion.Entry.Option> options = entry.getOptions();
        for(Suggest.Suggestion.Entry.Option option : options) {

            Document doc = new Document();

            doc.append("text",option.getText().toString());                 

            results.add(doc);
        }
    }    

sendJsonResult(results, resp);                  

Answer 3

But I'm running into the error "field "suggest" doesn't have type 'completion'. My mapping looks like this: code .field("suggest") .startObject() .field("type", "completion") .field("index_analyzer","simple") .field("search_analyzer","simple") .endObject()

It sounds like, that your mapping is not applied correctly. Did you check it out?

Based on the mapping you provided, I think you are missing the properties around your mapping. Try the following mapping:

XContentFactory.jsonBuilder().startObject()
  .startObject("properties")
    .startObject("suggest")
      .field("type", "completion")
    .endObject()
  .endObject()
.endObject()

Btw, SimpleAnalyzer is the default Analyzer for the suggestions. Thus, you need not define it explicitly.

Answer 4

To anyone who still needs this. The code snippet below works with ES v 6.3:-

CompletionSuggestionBuilder suggestionBuilder = new CompletionSuggestionBuilder("<field_name>").prefix("<search_term>");

        SearchRequestBuilder requestBuilder =
                oaEsClient.client().prepareSearch("<index_name>").setTypes("<type_name>")
                .suggest(new SuggestBuilder().addSuggestion("<suggestion_name>",suggestionBuilder))
                .setSize(20)
                .setFetchSource(true)
                .setExplain(false)
                ;
        SearchResponse response = requestBuilder.get();
        Suggest suggest = response.getSuggest();