code: func apiBase(w http.ResponseWriter, r *http.Request) {
  	const emptyJSON = "{}"
  	// Provide a simple /v2/ 200 OK response with empty json response.
  	w.Header().Set("Content-Type", "application/json")
  	w.Header().Set("Content-Length", fmt.Sprint(len(emptyJSON)))
  
  	fmt.Fprint(w, emptyJSON)
  }
docs: // apiBase implements a simple yes-man for doing overall checks against the
  // api. This can support auth roundtrips to support docker login.