cniAddServerCalled = true
		if serverErr {
			res.WriteHeader(http.StatusInternalServerError)
			res.Write([]byte("server not happy"))
			return
		}
		res.WriteHeader(http.StatusOK)
		res.Write([]byte("server happy"))
	}))

	return testServer.URL, func() bool {
		testServer.Close()
		return cniAddServerCalled
	}
}

# for the file, adds it to the host KUBECONFIG, and creates a mount for it. Note that we use a copy
# of the original file, so that the container can write to it.
add_KUBECONFIG_if_exists () {
  if [[ -f "$1" ]]; then
    local local_config
    local_config="$(mktemp)"
    cp "${1}" "${local_config}"