通过 Nest 中的 SearchRequest 类设置索引名称

Question

I use Nest client to use ElasticSearch .I want to search in ElasticSearch :

SearchRequest countRequest = new SearchRequest
{
  //Somthing
};

client.Search<Post>(countRequest);

On other hand :

client.Search<Post>(s=>s.Index("IndexName").Query(...))

How i can set index name by SearchRequest class search ?

Answer 1

This is for those using newer versions of NEST. In 2.0.1, I am unable to find the Indices property in SearchRequest . However, you can pass them in through the constructor:

var request = new SearchRequest<Post>("IndexName", "TypeName");

I map the index and type on the ConnectionSettings like so.

ConnectionSettings settings = new ConnectionSettings("url");
settings.MapDefaultTypeIndices(t => t.Add(typeof(Post), "IndexName"));
settings.MapDefaultTypeNames(t => t.Add(typeof(Post), "TypeName"));

Other ways to tell NEST the index and type:

client.Search<Post>(s => s.Index("IndexName").Type("TypeName").From(0));

or apply the ElasticsearchTypeAttribute on the type.

[ElasticsearchType(Name = "TypeName")]
public class Post{ }

Answer 2

SearchRequest contains an Indices property, so that you can specify multiple indices to search across. In your case, you could just pass the single index like so:

var request = new SearchRequest
{
    Indices = new IndexNameMarker[] { "IndexName" }
};

Another option would be to map your Post type to the index it belongs to, and use the typed SearchRequest<T> to let NEST infer the index name.

Answer 3

I was trying to solve a bit different task with ES v5 (json request was pushed from the file) but also had the same problem with setting the indexName. So, my solution was to add index querystring parameter. Using this in integration tests:

public static class ElasticSearchClientHelper
{
    public static ISearchResponse<T> SearchByJson<T>(this IElasticClient client, string json, string indexName, Dictionary<string, object> queryStringParams = null) where T : class
    {
        var qs = new Dictionary<string, object>()
        {
            {"index", indexName}
        };
        queryStringParams?.ForEach(pair => qs.Add(pair.Key, pair.Value));

        using (var stream = new MemoryStream(Encoding.UTF8.GetBytes(json)))
        {
            var searchRequest = client.Serializer.Deserialize<SearchRequest>(stream);
            ((IRequestParameters)((IRequest<SearchRequestParameters>)searchRequest).RequestParameters).QueryString = qs;
            return client.Search<T>(searchRequest);
        }
    }
}