type Some struct {
	Name      string
	CreatedAt time.Time
}

func main() {
	schemas := make(openapi3.Schemas)
	g := openapi3gen.NewGenerator(
		openapi3gen.UseAllExportedFields(),
		openapi3gen.CreateComponentSchemas(openapi3gen.ExportComponentSchemasOptions{
			ExportComponentSchemas: true,
		}),
	)

	ref, err := g.NewSchemaRefForValue(&Some{}, schemas)
	if err != nil {
		panic(err)
	}

	schema, _ := json.MarshalIndent(ref, "", "  ")
	fmt.Println(string(schema))
}