async.js

const setTokenAfterware = new ApolloLink(async (operation, forward) => {
  return forward(operation).map(async res => {
    const context = operation.getContext();
    const { response: { headers } } = context;

    const token = headers.get["x-token"];
    const refreshToken = headers.get["x-refresh-token"];

    if (token) {
      await AsyncStorage.setItem("token", token);
    }
    if (refreshToken) {
      await AsyncStorage.setItem("refreshToken", refreshToken);
    }

    return res;
  });
});