Is there a way to deserialize properties which have special charaters in names with ElasticLowLevelClient.SearchAsync? - elasticsearch-net

Question

I have logstash pushing logs into elasticsearch which automatically inserts the #timestamp field into each doc. I used Elasticsearch.Net instead of NEST in this project.
Each doc looks something like:
{
"Origin": 0,
"VisitorId": "49f843eb-be38-4912-a3b8-277841cd709d",
"CompanyId": 1,
"ActivityType": 21,
"Referer": "http://cn.bing.com/search?q=sogou&src=IE-SearchBox&FORM=IE10SR",
"ProductId": 1,
"version": "1.0",
"Url": "http://localhost:8001/Product/Detail/1",
"DeviceType": 1,
"#timestamp": "2017-03-21T02:04:13.136Z",
"UserId": 4,
"host": "ZBL-PC",
"#version": "1",
"IpAddress": "14.197.145.136",
"timestamp": "2017-03-21T02:04:13.136Z"
}
Currently, my search query looks like:
var res = client.SearchAsync<SearchResult<ProductVisit>>(index: _indexName,
type: "viewsingleproduct",
body: new PostData<object>(new
{
size = 10
}));
public class ProductVisit
{
public int? UserId { get; set; }
public Guid? VisitorId { get; set; }
public int DeviceType { get; set; }
public string timestamp { get; set; }
public int CompanyId { get; set; }
public long ProductId { get; set; }
}
public class Hit<TDocument>
{
public TDocument _source { get; set; }
}
public class Hits<TDocument>
{
public int total { get; set; }
public List<Hit<TDocument>> hits { get; set; }
}
public class SearchResult<TDocument>
{
public Hits<TDocument> hits { get; set; }
}
The Elasticsearch.Net way of retrieving docs is to declare a DTO which can be automatically deserialized into from the json in the response. However, in this case, I cannot declare a property that is a valid C# property name such that #timestamp values can be filled into.
In Nest which uses Newtonsoft.json, I can specify the actual field name in elasticsearch by attribute annotations (I remember JsonProperty will do the trick and also NEST has its own attribute that lets you specify the property name). However, Elasticsearch.Net doesn't use Newtonsoft.json internally. It uses SimpleJson which could've supported similar tricks via DataMember attribute but it requires SIMPLE_JSON_DATACONTRACT preprocessor switch to be enabled and Elasticsearch.Net disabled it by default.
Currently my solution is to copy #timestamp field into timestamp in logstash config, as shown in the json doc above. But it is a hack.
I originally had problems in the request side where official examples mostly construct queries using anonymous types like this:
new
{
term = new
{
_TopicPostId = new {
value = 4
}
}
},
But occasionally I need to construct queries with field names containing special characters. I finally figured out I could use Dictionary instead of anonymous types and it worked. For example:
new {
range = new Dictionary<string, object>{{
"#timestamp",
new
{
gte = "now-1d/d",
lte = "now/d"
}
}}
},