@brouberol just posting the Qs we have from Slack here for visibility (cc @Sfaci):

1. Is there a standard way to use config files for storing environment variables (db connection creds)?

2. Currently there is a frontend app (vuejs) silo'd in a subdirectory of the backend app (stripped down version of service-template-node) - both are served from different ports:
   • Is it reasonable to assume that we can map the different ports to separate domains or subdomains?
   • Should frontend + backend be in the same container or different containers?
   • Can the FE/BE container(s) be configured with a blubber file?

Is there a standard way to use config files for storing environment variables (db connection creds)?

TLDR: there is a way to commit secrets and have them be usable within your charts.

What we did for Superset was define a DB connection URI containing a <PASSWORD> placeholder that we later-on replace with the actual password. Because the password is secret, we only commit it to the private puppet repo, via which we render a special YAML file on the deployment server containing secrets/passwords only.

Is it reasonable to assume that we can map the different ports to separate domains or subdomains?

Do you mean DNS (sub)domains? If so, there is a way, but it requires just a bit of elbow grease. It can be done though.

However, what I'd do is slightly different, and it mirrors what was done for Superset. We have a single DNS domain (in our case, superset.wikimedia.org), and traffic reaches an nginx reverse proxy, that either proxies the traffic to the frontend container if the url path starts with e.g. /static and to the backend for anything else.

This is what this nginx config does.

Should frontend + backend be in the same container or different containers?

I'd tend to say different containers.

Can the FE/BE container(s) be configured with a blubber file?

Yes! In fact, we did exactly that for Superset

On slack, @Sfaci mentioned

About how the application is configured, at this moment, we have only a config.yaml file per environment but I don't know if we should declare some environment variables.

I would advise for a single way of configuring the application: either a config file _or_ environment variables. It'd be easier to maintain and override over time. Having a yaml file as a source of configuration is perfectly reasonable!