Exact array match in elasticsearch. size() -> issue#3094

gistfile1.txt

{
    "query" : {
        "filtered" : {
            "query" : {
                "term" : {
                    "tags" : "foo"
                }
            },
            "filter" : {
                "script" : {
                    "script" : "doc['tags'].values.size() == 1" 
                }
            }
        }
    }
}