ElasticSearch - Metric aggregation for any exist field

Question

How I can find min value for any exist field? This is docs

{
    "price": 15,
    "size": 14,
    "weight": 10
}
{
    "price": 19,
    "size": 10
}
{
    "price": 17,
    "size": 2
}

I want find min value for any exist field. Result should be like this

"aggregations": {
    "price_min": {
         "value": 15
     },
     "size_min": {
         "value": 2
     },
     "weight_min": {
         "value": 10
     }
}