auth0-react get token outside of react component

app.tsx

// your app.tsx
const {
  getAccessTokenSilently,
  loginWithRedirect,
  user,
  isAuthenticated,
  isLoading,
} = useAuth0();
  
useEffect(() => {
  if (!isLoading) {
    if (!isAuthenticated) {
      loginWithRedirect();
      return;
    }

    setAuthTokenGetter(getAccessTokenSilently);
  }
}, [isAuthenticated, isLoading]);

network.ts

// your network instance file
let authTokenGetter;
export const setAuthTokenGetter = (fn) => {
	authTokenGetter = fn;
};

export async function getAuthToken(): Promise<string | null> {
	return new Promise((res, rej) => {
		const getToken = async () => {
			if (authTokenGetter) {
				const accessToken = await authTokenGetter();
				if (!accessToken) {
					rej(null);
				}
				res(`Bearer ${accessToken}`);
			}

			setTimeout(() => {
				getToken();
			}, 500);
		};

		return getToken();
	});
}