Apollo Client config with appsync subscription

Question

graphql-client.js
 
  const authClientConfig = {
  url: process.env.NEXT_PUBLIC_APPSYNC_GRAPHQL_ENDPOINT,
  region: process.env.NEXT_PUBLIC_REGION,
  auth: {
    type: "AMAZON_COGNITO_USER_POOLS",
    jwtToken,
  },
};
const link = ApolloLink.from([
  createAuthLink({
    url: authClientConfig.url,
    region: authClientConfig.region,
    auth: authClientConfig.auth,
  }),
  createSubscriptionHandshakeLink({
    url: authClientConfig.url,
    region: authClientConfig.region,
    auth: authClientConfig.auth,
  }),
]);

const FinedeedsAppClient = new ApolloClient({
  link,
  cache: new InMemoryCache(),
});

return FinedeedsAppClient;


package.json

aws-appsync-subscription-link : ^3.0.11
@apollo/client: ^3.6.8
apollo-link-http: ^1.5.17
aws-appsync-auth-link: ^3.0.7
apollo-link : ^1.2.14

I'm using nextjs on frontend and getting below error after initializing apollo client with aws-appsync subscription

TypeError: Cannot read properties of undefined (reading 'subscriptionFailedCallback')

Answer 1

You might need to disable strict mode in your next.config.js file as reported here.