I do something similar but my data is not that important, as most of you guys work on - I have a very high rate of data being input from users for curating purposes in a bioinformatics lab..So I load the data onto a mongodb cluster and run the elasticsearch-river-mongodb [1] to keep the elasticsearch in sync with the mongodb.. I do not know whether it solves this problem - but I am happy that I have data safe in mongodb - any inputs regarding my method would be appreciated..
So you are protecting your data from unsafe Elasticsearch by storing it in an even more unsafe MongoDB[1]? You should probably put a database that knows how to store data somewhere in your stack and learn to use that.
[1]https://github.com/richardwilly98/elasticsearch-river-mongod...