I’m looking for a way to provide my app with a configuration file without baking it into the container. If you’re familiar with Kubernetes, I’m looking for ConfigMap or Secret equivalent, roughly something like “attach this YAML file to a directory in the running container”. Is there a way to do it?
To be clear — this is not about Fly’s fly.toml, but rather my own app’s configuration file.
Depending on the size on the config file, you may be in luck… try Secrets and Fly Apps.
Secrets are available as environment variables to the Fly VMs.
Correct me if I’m wrong — my understanding is that Fly secrets are only environment variables, not a file the way that Kubernetes Secret and ConfigMap would present itself to the container, yes?
I have a… 50+ line YAML file that I would like to keep as YAML instead of base64 encoding them to environment variable 
I suppose the alternative solution is to “download that configuration on boot from elsewhere”, but that doesn’t sound very ideal 
Correct, fly secrets is env variables.
You may have already looked this up, posting here just for cross-reference.
https://community.fly.io/t/mount-config-file-into-existing-docker-image
Ah that’s helpful, thank you. Downloading configuration from remote location tracks with my guess, thanks!