Given a JSON file of base elements, this will apply a set of overrides to that JSON file from data defined in another file.

Basic usage:

go run main.go base.json overrides.json

Specifying the output file:

go run main.go base.json overrides.json overriden.json

Let's say you have two configs, one for your staging environment and one for production. Some of the elements between environments may be the same, such as the name of your company. However, other elements like the environment itself will differ. While the configs below are small, imagine one with many more elements. Over 50% of these elements might be the same, so it can be a pain having to keep them in sync if an element changes that is the same in both of them. Instead you could keep a file that is just the elements that differ from the base config then apply those to the base config to get your new, final config.

base.json

{
  "environment": "production",
  "company": "Acme Corp"
}

overrides.json

{
  "environment": "staging"
}

output.json

{
  "company": "Acme Corp",
  "environment": "staging"
}

go test