Add GraphQLDemo

Author: johnnyoshika

src/App.js

@@ -3,6 +3,7 @@ import logo from './logo.svg';
 import './App.css';
 
 import LambdaDemo from './LambdaDemo';
+import GraphQLDemo from './GraphQLDemo';
 
 const App = () => {
   return (
@@ -13,6 +14,7 @@ const App = () => {
           Edit <code>src/App.js</code> and save to reload.
         </p>
         <LambdaDemo />
+        <GraphQLDemo />
       </header>
     </div>
   );

src/GraphQLDemo/index.js

@@ -0,0 +1,18 @@
+import React from 'react';
+import { useQuery } from '@apollo/react-hooks';
+import { gql } from 'apollo-boost';
+
+const GraphQLDemo = () => {
+  const { data } = useQuery(gql`
+    query {
+      hello
+    }
+  `);
+  return (
+    <div>
+      A greeting from the GraphQL server: {data ? data.hello : ''}
+    </div>
+  );
+};
+
+export default GraphQLDemo;