Apollo graphql setting header to authmiddleware not working

Question

I am using react-native and apollo client and if I try to set header by jwt stored in AsyncStorage, it seems not working.
Other resolvers which doesn't need header works very well. My code is like below.

import { ApolloClient } from "apollo-client";
import { InMemoryCache } from "apollo-cache-inmemory";
import { ApolloLink } from "apollo-link";
import { createHttpLink } from "apollo-link-http";
import AsyncStorage from "@react-native-community/async-storage";

const cache = new InMemoryCache();

const getToken = async () => {
  const token = await AsyncStorage.getItem("jwt");

  if (token) {
    return token;
  } else {
    return null;
  }
};

const httpLink = new createHttpLink({
  uri: ""
});

const authLink = new ApolloLink((operation, forward) => {
  operation.setContext({
    headers: {
      "X-JWT": getToken()
      // this is where I set headers by getToken function
      // If I change function getToken to real token in string type, it works then
    }
  });

  return forward(operation);
});

const client = new ApolloClient({
  cache: cache,
  link: authLink.concat(httpLink)
});

export default client;

Like I commented in the code, calling getToken function is not working what I expected. I think I should have more knowledge of async and await, but I don't get it what is the real problem.

The error message I get from console is jwt malformed. Please let me know how to fix this problem

Answer 1

Try to use setContext directly

import { ApolloClient } from "apollo-client";
import { createHttpLink } from "apollo-link-http";
import { setContext } from "apollo-link-context";
import { InMemoryCache } from "apollo-cache-inmemory";
import AsyncStorage from "@react-native-community/async-storage";

const httpLink = createHttpLink();

const authLink = setContext(async (_, { headers }) => {
  const token = await AsyncStorage.getItem("jwt");

  return {
    headers: {
      ...headers,
      "X-JWT": token || null
    }
  };
});

const client = new ApolloClient({
  link: authLink.concat(httpLink),
  cache: new InMemoryCache()
});

export default client;