How to read the JSON output of a faceted search query?

1
votes

I am having Movies that belong to a genre and have multiple ratings. With ElasticSearch, I want to do a faceted search on Genres first, and then Ratings.

I was reading about the idea here: http://www.elasticsearch.org/guide/reference/api/search/facets/

But I am confused how to understand the output of this Curl query:

curl -X POST "http://localhost:9200/movies/_search?pretty=true" -d '
 {
    "query" : { "query_string" : {"query" : "T*"} },
    "facets" : {
      "categories" : { "terms" : {"field" : "categories"} }
    }
  }
'
{
  "took" : 35,
  "timed_out" : false,
  "_shards" : {
    "total" : 5,
    "successful" : 5,
    "failed" : 0
  },
  "hits" : {
    "total" : 3,
    "max_score" : 1.0,
    "hits" : [ {
      "_index" : "movies",
      "_type" : "movie",
      "_id" : "13",
      "_score" : 1.0, "_source" : {"category_id":2,"created_at":"2013-05-03T16:40:21Z","description":null,"title":"Tiny Plastic Men","updated_at":"2013-05-03T16:40:21Z","user_id":null}
    }, {
      "_index" : "movies",
      "_type" : "movie",
      "_id" : "32",
      "_score" : 1.0, "_source" : {"category_id":14,"created_at":"2013-05-03T16:55:02Z","description":null,"title":"The Extreme Truth","updated_at":"2013-05-03T16:55:02Z","user_id":null}
    }, {
      "_index" : "movies",
      "_type" : "movie",
      "_id" : "39",
      "_score" : 1.0, "_source" : {"category_id":7,"created_at":"2013-05-03T16:55:02Z","description":null,"title":"A Time of Day","updated_at":"2013-05-03T16:55:02Z","user_id":null}
    } ]
  },
  "facets" : {
    "categories" : {
      "_type" : "terms",
      "missing" : 3,
      "total" : 0,
      "other" : 0,
      "terms" : [ ]
    }
  }

I am having some movies that start with a 'T', but additionally I would expect movies from the Genre/Category 'Thriller'.

Therefore, what can I read from the JSON above?

2
elasticsearch

2 Answers

3
votes

It seems like your facet does not match any fields in your document you should probably use:

curl -X POST "http://localhost:9200/movies/_search?pretty=true" -d '
 {
    "query" : { "query_string" : {"query" : "T*"} },
    "facets" : {
      "categories" : { "terms" : {"field" : "category_id"} }
    }
  }
'

then you sould get a list of category_id and a count of documents in each category_id