We must admit that making any changes/updates to an existing document in ElasticSearch is really messy. Some reasons for that might be:
1. Using scripts: even when you can merge existing fields built-in, using scripts and especially painless is just not right for simple tasks. 1. Using metafields: sometimes just in order to get or update the document, you must hold Parent ID or Routing key. It doesn't feel natural.
I wish there would be a simple document editor which shows me the current version of the document, allows me to edit the document (just like in notepad) and then overwrite the document with this version.
Simple screenshots from RoboMongo for demonstration: ![robomongo|690x353](upload://85tCMp4LKoZVT12h0R9BoTZBspj.png)![robomongo2|649x500](upload://AoSzgDlfCLkDxh2B0We9OYjtsaO.png)