Amplify mock subscription error: "Connection failed: An invalid or illegal string was specified"

Describe the bug The same code that works when subscribing to an AppSync endpoint doesn’t work when using amplify mock.

Amplify CLI Version 4.13.1

To Reproduce

1. Create react app
2. run amplify init
3. add graphql api with api key (for test i’ve tried with api key and cognito user pool)
4. npm install amplify modules
5. deploy to server
6. copy paste code below
7. run aginst server and see connection
8. run amplify mock and see error

Code:

import React, { useEffect } from 'react';
import Amplify from '@aws-amplify/core';
import API from '@aws-amplify/api';
import PubSub from '@aws-amplify/pubsub';
import config from './aws-exports';
import { onCreateMyType } from './graphql/subscriptions';

Amplify.configure(config);
PubSub.configure(config);

// Amplify.Logger.LOG_LEVEL = 'DEBUG';

function App() {
  useEffect(() => {
    let subscription;

    const run = () => {
      subscription = API.graphql({
        query: onCreateMyType,
      }).subscribe({
        next: response => console.log('response', response),
        error: response => console.log('error response', response),
      });
    };

    run();

    return () => subscription.unsubscribe();
  }, []);

  return <div>Pub Sub Test</div>;
}

export default App;

Expected behavior Be able to test subscriptions locally

Desktop (please complete the following information):

• OS: macOS
• Node Version: v12.10.0

[yuth]

The only way to use it would be to use older version of Amplify JS libraries (@aws-amplify/pubsub@1.x.x), which may have bug that got fixed along the way

[github-actions[bot]]

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