Elasticsearch NEST Reuse ElasticClient for different index query - elasticsearch

Question

How can I register ElasticClient as singleton in a .NET Core application but still able to specify the different index during the query?
For example:
In Startup.cs I register an elastic client object as singleton, by only mentioning the URL without specifying the index.
public void ConfigureServices(IServiceCollection services)
{
....
var connectionSettings = new ConnectionSettings(new Uri("http://localhost:9200"));
var client = new ElasticClient(connectionSettings);
services.AddSingleton<IElasticClient>(client);
....
}
Then when injecting ElasticClient singleton object above, I would like to use it for different indices in 2 different queries.
In the class below, I want to query from an index called "Apple"
public class GetAppleHandler
{
private readonly IElasticClient _elasticClient;
public GetAppleHandler(IElasticClient elasticClient)
{
_elasticClient = elasticClient;
}
public async Task<GetAppleResponse> Handle()
{
// I want to query (_elasticClient.SearchAsync<>) using an index called "Apple" here
}
}
From code below I want to query from an index called "Orange"
public class GetOrangeHandler
{
private readonly IElasticClient _elasticClient;
public GetOrangeHandler(IElasticClient elasticClient)
{
_elasticClient = elasticClient;
}
public async Task<GetOrangeResponse> Handle()
{
// I want to query (_elasticClient.SearchAsync<>) using an index called "Orange" here
}
}
How can I do this? If it's not possible, can you suggest other approach that will allow me to inject ElasticClient through .NET Core dependency injection and at the same time also allow me to query from 2 different indices of the same ES instance?

Answer 1

Just need to specify the index on the request
var defaultIndex = "person";
var pool = new SingleNodeConnectionPool(new Uri("http://localhost:9200"));
var settings = new ConnectionSettings(pool)
.DefaultIndex(defaultIndex)
.DefaultTypeName("_doc");
var client = new ElasticClient(settings);
var searchResponse = client.Search<Person>(s => s
.Index("foo_bar")
.Query(q => q
.Match(m => m
.Field("some_field")
.Query("match query")
)
)
);
Here the search request would be
POST http://localhost:9200/foo_bar/_doc/_search
{
"query": {
"match": {
"some_field": {
"query": "match query"
}
}
}
}
foo_bar index has been defined in the search request
_doc type has been inferred from the global rule on DefaultTypeName("_doc")