Generate QueryString with named fields using nest elastic search client

Question

Im currently using Nest elastic clien, so run basic search terms like this:

.Query(q => q.QueryString(qs=>qs.Query("user search term")));

and i'm also combining those basic search terms with facets filters like this:

.Query(
    q => q.QueryString(qs => qs.Query("user search term"))
    && q.Terms(t => t.Brand, new string[] {"brand1", "brand2"})
    && q.Terms(t => t.Colour, new string[] {"blue", "black"})
    && q.Range(r => r.From(50).To(100).OnField(f => f.Price))
);

however I'm struggling to run custom query string searches that apply to specific fields. The search querystring will be passed into my app and therefore i wont know the specific fields that im searching so i cannot use the .OnField() method on the client

For example a want to be able to pass in a querystring that searches by brand, gender and colour at the same time. From looking at the Elastic search query DSL I think I should be able to pass in a querystring that names the fields like so:

.Query(q => q.QueryString(qs => qs.Query("brand:brand1 AND gender:male AND colour(blue)")));

but this doesnt work and returns no results. How can I generate a querystring to search on specific fields the Nest client?

Also is there any way of viewing the generated query from the nest SearchDescriptor?

You can see what NEST is sending to Elasticsearch via this previous question: stackoverflow.com/questions/23703570/… — Paige Cook
thank you seeing the json generated helped me realise that the query string generated using the nest client was exactly how i needed it to be, and therefore the problem was in my original mapping on the index. As a also generate term queries on the brand and gender fields they were set as FieldIndexOption.not_analyzed which was the problem. — Steve

Mohammad Hatami Mohammad Hatami · Accepted Answer · 2018-12-05T09:05:02

You can use bool query

List<QueryContainer> shoudQuery = new List<QueryContainer>();

shoudQuery.Add(new MatchQuery()
    {
       Field = "brand",
       Query = "brand1",    
    });
shoudQuery.Add(new MatchQuery()
    {
       Field = "gender",
       Query = "male",    
    });
shoudQuery.Add(new MatchQuery()
    {
       Field = "colour",
       Query = "blue",    
    });


QueryContainer queryContainer = new BoolQuery
        {
             Should = shoudQuery.ToArray(),
             Must = new QueryContainer[] { new MatchAllQuery() },
             MinimumShouldMatch = 3,

         };


var result = Client.Search(s => s.Size(resultSize).Query(q => queryContainer)

if you want 3 and =>MinimumShouldMatch = 3
if you want 2 of 3 =>MinimumShouldMatch = 2

...

Generate QueryString with named fields using nest elastic search client

1 Answers