Write a custom resolver

Implement fuda.RefResolver when your application needs a URI scheme that Fuda does not provide.

type Resolver struct{}

func (Resolver) Resolve(ctx context.Context, uri string) ([]byte, error) {
    if !strings.HasPrefix(uri, "config://") {
        return nil, fmt.Errorf("unsupported URI: %s", uri)
    }

    return []byte("value from the config service"), nil
}

Pass the resolver to the builder:

loader, err := fuda.New().
    FromFile("config.yaml").
    WithRefResolver(Resolver{}).
    Build()

Fuda calls Resolve(context.Context, string) ([]byte, error) for ref and refFrom values. Respect the context so WithTimeout can limit network work. Make the resolver safe for concurrent calls.

Next step

Review the reference tag syntax.