GetMapping not working for Nest client in Elasticsearch - json

Question

perhaps some of the documentation http://nest.azurewebsites.net/ is old because i'm running into a at least few issues...
i've got a json object 'search'. i am getting null returned from the GetMapping function. well, it returns a Nest.RootObjectMapping object, but all fields within are null. i can get the mapping fine using Sense or regular curl.
var mapping = elasticClient.GetMapping<MyJsonPOCO>();
any ideas?
also, just as example of other things going wrong, this search works, but adding 'fields' to it does not (i got the fields declaration per the documentation)
var result = elasticClient.Search<MyJsonPOCO>(s => s
.Query(q => q
.QueryString(qs => qs
.OnField(e => e.Title)
.Query("my search term"))));
if i use this query with the fields added (to just return 'title'), i get a json parser issue.
var result = elasticClient.Search<MyJsonPOCO>(s => s
.Fields(f => f.Title)
.Query(q => q
.QueryString(qs => qs
.OnField(e => e.Title)
.Query("my search term"))));
here's the error for that one:
An exception of type 'Newtonsoft.Json.JsonReaderException' occurred in Newtonsoft.Json.dll but was not handled in user code
Additional information: Error reading string. Unexpected token: StartArray. Path 'hits.hits[0].fields.title', line 1, position 227.

Answer 1

Elasticsearch 1.0 changed the way fields are returned in the search response
You need the NEST 1.0 beta1 release to work with Elasticsearch 1.0
http://www.elasticsearch.org/blog/introducing-elasticsearch-net-nest-1-0-0-beta1/
See also this github issue for more background information on the why and how to work with fields from 1.0 forward:
https://github.com/elasticsearch/elasticsearch-net/issues/590