ElasticSearch document field size

Question

I am trying to obtain metadata about the document types within an elasticsearch index. Any ideas on how I could retrieve the maximum length of a string field?

Answer 1

After enabling dynamic scripting the following did the trick for me (provided there where no nulls):

POST /myIndex/_search?Document' -d '
{
    "query" : {
        "filtered" : {
            "filter" : {
                "exists" : { "field" : "someField" }
            }
        }
    },    
    "aggs" : {
        "max_length" : { "max" : { "script" :doc['someField'].value.length()" } }
    }
}