How to set IndexOption = docs - elasticsearch

Question

I need to get result below with NEST (Elastic Search .NET client)
"detailVal": {
"name": "detailVal",
"type": "multi_field",
"fields": {
"detailVal": {
"type": "string"
},
"untouched": { // <== FOCUS 2
"type": "string",
"index": "not_analyzed",
"omit_norms": true,
"include_in_all": false,
"index_options": "docs" // <== FOCUS 1
}
}
}
I have done so far
[ElasticProperty(OmitNorms = true, Index = FieldIndexOption.not_analyzed, IncludeInAll = false, AddSortField = true)]
public string DetailVal { get; set; }
which gets me
"detailVal": {
"name": "detailVal",
"type": "multi_field",
"fields": {
"detailVal": {
"type": "string",
"index": "not_analyzed",
"omit_norms": true,
"include_in_all": false
},
"sort": { // <== FOCUS 2
"type": "string",
"index": "not_analyzed"
}
}
}
so, any idea how to
add "index_options": "docs" (I found IndexOptions.docs but it is not valid as Attribute)
change sort to untouched

Answer 1

The attribute based mapping only gets you so far. It's good enough if you only need to change names and set simple properties.
The recommended approach is to use client.MapFluent()
See https://github.com/Mpdreamz/NEST/blob/master/src/Nest.Tests.Unit/Core/Map/FluentMappingFullExampleTests.cs#L129
For an example how to set index_options
And line 208:
https://github.com/Mpdreamz/NEST/blob/master/src/Nest.Tests.Unit/Core/Map/FluentMappingFullExampleTests.cs#L208
To see how you can create your own multi_field mapping.
You can even combine both approaches:
client.MapFluent<MyType>(m=>m
.MapFromAttributes()
//Map what you can't with attributes here
);
client.Map() and client.MapFromAttributes() will most likely be removed at some point.