Elasticsearch Popular Keywords

Question

Does elasticsearch provide a way to keep track of popular keywords? For example, at a given time period, I would like to know the keywords that appear the mostly frequently in queries.

If elasticsearch does not have such a feature, what would be a good way to implement it using elasticsearch?

Thanks!

Answer 1

I don't think there is a build-in way for that, but it should be quite easy to achieve via a terms facet

What you'd have to do is:

1. Save all query keywords along with a timestamp in an elasticsearch index
2. Run a match_all query filtered by the time interval you are interested in and apply a term facet onto it

Unfortunately I don't have the time to write you an example, but that should lead you to the solution.

Here is an example:

// Demo index
curl -XDELETE 'http://localhost:9200/queries/'
curl -XPUT 'http://localhost:9200/queries/'

// Add some data
curl -XPUT 'http://localhost:9200/queries/query/1' -d '
{ 
    "date": "2013-02-19T12:57:23", 
    "query": "Trying out ElasticSearch, so far so good?"
}'

curl -XPUT 'http://localhost:9200/queries/query/2' -d '
{ 
    "date": "2013-03-02T11:27:23", 
    "query": "Lets give ElasticSearch another try"
}'

curl -XPUT 'http://localhost:9200/queries/query/3' -d '
{ 
    "date": "2013-04-02T08:27:23", 
    "query": "OK, why dont we stick to SOLR?"
}'

curl -XPUT 'http://localhost:9200/queries/query/4' -d '
{ 
    "date": "2013-04-19T11:27:23", 
    "query": "Couse ElasticSearch is so much cooler, its bonsai cool"
}'

// Query it
curl -XGET 'http://localhost:9200/queries/query/_search?pretty=true' -d '
{
    "query" : {
        "filtered" : {
            "filter" : {
                "range" : {
                    "date" : {
                        "gte" : "2013-01-01T00:00:00",
                        "lt" : "2013-04-01T00:00:00"
                    }
                }
            },
            "query" : {
                "match_all" : {}
            }
        }
    },
    "facets": {
        "keywords": {
            "terms": {
                "field": "query"
            }
        }
    }
}
'

Adjust the date range in the query to see the changes of the output

Answer 2

The Approved answer not working anymore because Facets have been removed and replaced with terms aggregation instead.