AWS keys from secrets

[szabolcsgarda]

When you deploy the container by some kind of container management system (e.g.: Portainer) it would be useful if you could pass certain data as secrets (specifically AWS credentials, bucket name etc.), therefore they would not show up in the docker-compose file.
The way Portainer manages secrets is that it creates a file in the container, which contains the secret itself.

A possible (and usual) way to enable this feature is to allow users to pass <ENVIRONMENTAL_VARIABLE_NAME>_FILE environmental variable, which should contain the file path where the corresponding secret is. At container startup the entrypoint.sh should read in this file and copy its value to <ENVIRONMENTAL_VARIABLE_NAME>, therefore further commands and applications will be able to access the secret as environmental variable.
A project implements this feature: https://hub.docker.com/_/mysql

I am happy to implement this feature if others also consider it useful