Allow config file overlays

[blancharda]

Context

When managing configurations for multiple environments, there are often many duplicated settings/values across each configuration. A common pattern for simplifying the management of these kinds of configurations (used by Helm, Kustomize and others) is an overlay system, wherein multiple configuration files are provided at once, and values are set in priority order by whichever file "most recently" set them. This allows users to manage a set of base configurations with common values, and separate individual configurations for environment specific, or sensitive values.

Feature Request

• Allow the user to specify configuration files at deploy time via command line flag
• Collate the values into a single config

[UncleGedd]

👍 I like the idea of working with overlay files as opposed to individual configs, I'm not sure it entirely solves the problem for secrets but it's a good start. Tagging @jeff-mccoy because I think this sort of thing could also play into UDS Prod and maybe his next project

[blancharda]

Oh yea, no.. it absolutely doesn't SOLVE the problem of working with secrets.. but I think it could make our current workarounds simpler (i.e. having the ability to check in the bulk of a config for an environment, and only have to manage the secret parts via external file sharing or dynamic generation)