使用Java API的ElasticSearch完成建议器

时间:2016-02-01 18:15:05

标签: java elasticsearch

我在网上尝试了一些关于ElasticSearch的建议功能的示例代码,但我无法解决我对自动完成解决方案的问题

我的索引:

client.prepareIndex("kodcucom", "article", "1")
      .setSource(putJsonDocument("ElasticSearch: Java",
        "ElasticSeach provides Java API, thus it executes all operations " +
        "asynchronously by using client object..",
         new Date(),
         new String[]{"elasticsearch"},
         "Hüseyin Akdoğan")).execute().actionGet();

我使用了suggestbuilder来获取关键字,然后浏览内容“字段”,这里是由于没有结果而出现空指针异常的地方

CompletionSuggestionBuilder skillNameSuggest = new CompletionSuggestionBuilder("skillNameSuggest");

skillNameSuggest.text("lien");
skillNameSuggest.field("content");

SuggestRequestBuilder suggestRequestBuilder = client.prepareSuggest("kodcucom").addSuggestion(skillNameSuggest);

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

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

我是否缺少一些过滤器或输入条件才能获得结果?任何结果都应该可以,例如自动完成或找到记录。

编辑1:

这是我获得NPE的地方,我可以看到任何结果都没有从调试模式suggestResponse返回

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

编辑2: 我使用的是2.1.1版本的ElasticSearch Java API

编辑3: 我试图将迭代器行拆分成几个代码块,当将一组数据转换为迭代器时,NPE出现在最后一行,但没有太多帮助

Suggest tempSuggest = suggestResponse.getSuggest();

Suggestion tempSuggestion = tempSuggest.getSuggestion("skillNameSuggest");

Iterator tempIterator = tempSuggestion.iterator();

我看到了代码:

SuggestRequestBuilder suggestRequestBuilder = client.prepareSuggest("kodcucom").addSuggestion(skillNameSuggest);

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

已经包含一个空数组/数据集,我是否错误地使用了建议请求构建器?

2 个答案:

答案 0 :(得分:4)

为了使用完成功能,您需要专用一个字段,称为完成,您必须为其指定特殊映射。

例如:

"mappings": {
   "article": {
     "properties": {
      "content": {
        "type": "string"
      },
     "completion_suggest": {
      "type": "completion"}
     }
   }
}

completion_suggest字段是我们将用于上述代码示例中的自动完成功能的字段。在映射定义之后,数据必须索引如下:

curl -XPOST localhost:9200/kodcucom/article/1 -d '{
   "content": "elasticsearch",
   "completion_suggest": {
     "input": [ "es", "elastic", "elasticsearch" ],
     "output": "ElasticSearch"
   }
}'

然后可以使用Java API获取建议:

CompletionSuggestionBuilder skillNameSuggest  = new CompletionSuggestionBuilder("complete");
skillNameSuggest.text("es");
skillNameSuggest.field("completion_suggest");

SearchResponse searchResponse = client.prepareSearch("kodcucom")
        .setTypes("article")
        .setQuery(QueryBuilders.matchAllQuery())
        .addSuggestion(skillNameSuggest)
        .execute().actionGet();

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

List<CompletionSuggestion.Entry> entryList = compSuggestion.getEntries();
if(entryList != null) {
    CompletionSuggestion.Entry entry = entryList.get(0);
    List<CompletionSuggestion.Entry.Option> options =entry.getOptions();
    if(options != null)  {
        CompletionSuggestion.Entry.Option option = options.get(0);
        System.out.println(option.getText().string());
    }
}

答案 1 :(得分:0)

以下链接为您提供了有关如何创建建议者索引的详细信息。 https://www.elastic.co/blog/you-complete-me

现在,我使用异步Suggestionbuilder Java API根据术语生成建议。

 SearchRequestBuilder suggestionsExtractor = elasticsearchService.suggestionsExtractor("yourIndexName", "yourIndexType//not necessary", "name_suggest", term);
        System.out.println(suggestionsExtractor);
        Map<String,Object> suggestionMap = new HashMap<>();
        suggestionsExtractor.execute(new ActionListener<SearchResponse>() {
            @Override
            public void onResponse(SearchResponse searchResponse) {
               if(searchResponse.status().equals(RestStatus.OK)) {
                   searchResponse.getSuggest().getSuggestion("productsearch").getEntries().forEach(e -> {
                       e.getOptions().forEach(s -> {
                           ArrayList<Object> contents = new ArrayList<>();

                           suggestionMap.put(s.getText().string(), s.getScore());

                       });
                   });


               }

            }

            @Override
            public void onFailure(Exception e) {
                Helper.sendErrorResponse(routingContext,new JsonObject().put("details","internal server error"));
                e.printStackTrace();
            }
        });

以下是如何创建suggestionbuilder。

public SearchRequestBuilder suggestionsExtractor(String indexName, String typeName, String field, String term) {

        CompletionSuggestionBuilder csb = SuggestBuilders.completionSuggestion(field).text(term);
        SearchRequestBuilder suggestBuilder = client.prepareSearch()
                .suggest(new SuggestBuilder().addSuggestion(indexName, csb));
        return suggestBuilder;
    }