Creating an index Nest

How would I recreate the following index using Elasticsearch Nest API?

Here is the json for the index including the mapping:

{
    "settings": {
        "analysis": {
            "filter": {
                "trigrams_filter": {
                    "type":     "ngram",
                    "min_gram": 3,
                    "max_gram": 3
                }
            },
            "analyzer": {
                "trigrams": {
                    "type":      "custom",
                    "tokenizer": "standard",
                    "filter":   [
                        "lowercase",
                        "trigrams_filter"
                    ]
                }
            }
        }
    },
    "mappings": {
        "data": {
        "_all" : {"enabled" : true},
            "properties": {
                "text": {
                    "type":     "string",
                    "analyzer": "trigrams" 
                }
            }
        }
    }
}

Here is my attempt:

var newIndex = client.CreateIndexAsync(indexName, index => index
            .NumberOfReplicas(replicas)
            .NumberOfShards(shards)
            .Settings(settings => settings
                .Add("merge.policy.merge_factor", "10")
                .Add("search.slowlog.threshold.fetch.warn", "1s")
                .Add("mapping.allow_type_wrapper", true))
             .AddMapping<Object>(mapping => mapping
                .IndexAnalyzer("trigram")
                .Type("string"))
 );

The documentation does not mention anything about this?

UPDATE:

Found this post that uses var index = new IndexSettings()

and then adds Analysis with the string literal json.

index.Add("analysis", @"{json});

Where can one find more examples like this one and does this work?

Creating an index in older versions

There are two main ways that you can accomplish this as outlined in the Nest Create Index Documentation:

Here is the way where you directly declare the index settings as Fluent Dictionary entries. Just like you are doing in your example above. I tested this locally and it produces the index settings that match your JSON above.

        var response = client.CreateIndex(indexName, s => s
          .NumberOfReplicas(replicas)
          .NumberOfShards(shards)
          .Settings(settings => settings
             .Add("merge.policy.merge_factor", "10")
             .Add("search.slowlog.threshold.fetch.warn", "1s")
             .Add("mapping.allow_type_wrapper", true)
             .Add("analysis.filter.trigrams_filter.type", "nGram")
             .Add("analysis.filter.trigrams_filter.min_gram", "3")
             .Add("analysis.filter.trigrams_filter.max_gram", "3")
             .Add("analysis.analyzer.trigrams.type", "custom")
             .Add("analysis.analyzer.trigrams.tokenizer", "standard")
             .Add("analysis.analyzer.trigrams.filter.0", "lowercase")
             .Add("analysis.analyzer.trigrams.filter.1", "trigrams_filter")
           )
           .AddMapping<Object>(mapping => mapping
              .Type("data")
              .AllField(af => af.Enabled())
              .Properties(prop => prop
                 .String(sprop => sprop
                   .Name("text")
                   .IndexAnalyzer("trigrams")
                  )
               )
           )
       );

Please note that NEST also includes the ability to create index settings using strongly typed classes as well. I will post an example of that later, if I have time to work through it.

Creating index with NEST 7.x

Please also note that in NEST 7.x CreateIndex method is removed. Use Indices.Create isntead. Here's the example.

_client.Indices
    .Create(indexName, s => s
        .Settings(se => se
            .NumberOfReplicas(replicas)
            .NumberOfShards(shards)
            .Setting("merge.policy.merge_factor", "10")));