Elasticsearch plugin to classify documents

Question

Is there an elasticsearch plugin out there that would allow me to classify the documents that I enter in an index?

The best solution for me would be a classification

Answer 1

The basic idea is to use a terms aggregations, which will yield one bucket per term.

POST /_search
{
    "aggs" : {
        "genres" : {
            "terms" : { "field" : "genre" }
        }
    }
}

The response you'll get will be ordered by decreasing amount of term occurrences:

{
    ...

    "aggregations" : {
        "genres" : {
            "doc_count_error_upper_bound": 0, 
            "sum_other_doc_count": 0, 
            "buckets" : [ 
                {
                    "key" : "jazz",
                    "doc_count" : 10
                },
                {
                    "key" : "rock",
                    "doc_count" : 5
                },
                {
                    "key" : "electronic",
                    "doc_count" : 2
                },
            ]
        }
    }
}

If you're using Kibana, you can directly create a tag cloud visualization based on those terms.