elasticsearch : Nested Document Mapping not working

Question

I have following json structure in elastic search which stored @ http://localhost:9200/mongoindex/documents/ :

{
"text" : "OTesting1"
"otag" : "otag1"
"pages" : [{
      "text" : "1"
  "name" : "itag1"

    }, {
     "text" : "2"
     "name" : "itag2"
    }
]
}

I have created nested mapping as following to enable nested search and nested filter on it :

http://localhost:9200/mongoindex/documents/_mapping [PUT]

{
  "documents": {
    "properties": {
      "pages": {
        "type": "nested"
      }
    }
  }
}

Now executed following java code :

Settings settings = ImmutableSettings.settingsBuilder()
                .put("cluster.name", "xyz").build();
        Client client = new TransportClient(settings).addTransportAddress(new InetSocketTransportAddress("localhost", 9300));
        SearchResponse response = client.prepareSearch("mongoindex")
                .setTypes("documents")
                .setQuery(QueryBuilders.nestedQuery("documents", QueryBuilders.boolQuery().must(QueryBuilders.matchQuery("pages.text", "1"))).scoreMode("avg"))
                .execute()
                .actionGet();

but its giving me following exception :

> Exception in thread "main"
> org.elasticsearch.action.search.SearchPhaseExecutionException: Failed
> to execute phase [query], total failure; shardFailures
> {[kSKaBxjGTMSS352kukrYVw][mongoindex][0]:
> SearchParseException[[mongoindex][0]: from[-1],size[-1]: Parse Failure
> [Failed to parse source
> [{"query":{"nested":{"query":{"bool":{"must":{"match":{"pages.text":{"query":"1","type":"boolean"}}}}},"path":"documents","score_mode":"avg"}}}]]];
> nested: QueryParsingException[[mongoindex] [nested] nested object
> under path [documents] is not of nested type];
> }{[kSKaBxjGTMSS352kukrYVw][mongoindex][4]:
> SearchParseException[[mongoindex][4]: from[-1],size[-1]: Parse Failure
> [Failed to parse source
> [{"query":{"nested":{"query":{"bool":{"must":{"match":{"pages.text":{"query":"1","type":"boolean"}}}}},"path":"documents","score_mode":"avg"}}}]]];
> nested: QueryParsingException[[mongoindex] [nested] nested object
> under path [documents] is not of nested type]; }

Answer 1

You have to specify the path to your nested object in the Nested Query, in your case "path" : "pages". I'm not familiar with the Java syntax, but the equivalent REST request would look like this:

{
   "nested" : {
       "path" : "pages",
       "score_mode" : "avg",
       "query" : {
           "bool" : {
               "must" : [
                   {
                       "match" : {"pages.text" : "1"}
                   }
               ]
           }
       }
   }

}

Tangentially related, the last line of ElasticSearch error messages usually contains the info you need to debug (while the rest is pretty useless and/or repetitive). So this is the key part:

QueryParsingException[[mongoindex] [nested] nested object under path [documents] is not of nested type]; }