用于检索某些字段的 ElasticSearch NEST 库

Question

正在努力实现以下目标，

检索与给定 ID 和类型匹配的文章
检索匹配记录的选定字段

我已经用 Sense（chrome 插件）试过了，

POST /d3acampaign/article/_search
        {
            "fields": ["title","genre"] ,
            "query": {
                "filtered": {
                    "filter": {
                        "bool": {
                            "must": [{
                                    "term": {
                                    "id": "6"
                                }
                            },
                            {
                                    "term": {
                                    "genre": "metal"
                                }
                            }]
                        }
                    }
               }
            }
        }

对于 C# 代码，我正在尝试使用以下结构构建查询，

        FilterContainer fc = null;
        TermFilter title = new TermFilter()
        {
            Field = "id",
            Value = "6",
        };

        TermFilter genre = new TermFilter()
        {
            Field = "genre",
            Value = "metal",
        };

        fc = title & genre;
        QueryContainer qc = new FilteredQuery() { Filter = fc };
        var searchRequest = new SearchRequest
        {
            SearchType = Elasticsearch.Net.SearchType.QueryAndFetch,
            Query = qc,
            Indices = new IndexNameMarker[] {"journal"},
            Types = new TypeNameMarker[] { "article" },                
        };


        var r = client.SearchAsync<Article>(searchRequest);


        var l = (List<Article>) r.Result.Documents;

我能够运行此查询并获得匹配的记录，但我不确定如何指定要检索的选定字段。让我知道可以在 C# 代码中更改哪些内容以指定必要的字段。

提前致谢。

Answer 1

根据this回答你可以修改你的请求对象如下：

var searchRequest = new SearchRequest
{
    ...
    Fields = new List<PropertyPathMarker>
    {
        Property.Path<Article>(p => p.YourField)
    }
};

或者如果您决定使用 source filtering:

var searchRequest = new SearchRequest
{
    ...
    Source = new SourceFilter
    {
        Include = new []
        {
            Property.Path<Article>(p => p.YourField)
        }
    } 
};

希望对您有所帮助。

用于检索某些字段的 ElasticSearch NEST 库

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