How to upload file to AWS S3 using AWS AppSync : <p>Following <a href="https://docs.aws.amazon.com/appsync/latest/devguide/building-a-client-app-react.html#complex-objects" rel="noreferrer">this docs/tutorial</a> in AWS AppSync Docs.</p>

<p>It states:</p>

<blockquote>
  <p>With AWS AppSync you can model these as GraphQL types. If any of your mutations have a variable with bucket, key, region, mimeType and localUri fields, the SDK will upload the file to Amazon S3 for you.</p>
</blockquote>

<p>However, I cannot make my file to upload to my s3 bucket. I understand that tutorial missing a lot of details. More specifically, the tutorial does not say that the <code>NewPostMutation.js</code> needs to be changed.</p>

<p>I changed it the following way:</p>

<pre><code>import gql from 'graphql-tag';

export default gql`
mutation AddPostMutation($author: String!, $title: String!, $url: String!, $content: String!, $file: S3ObjectInput ) {
    addPost(
        author: $author
        title: $title
        url: $url
        content: $content
        file: $file
    ){
        __typename
        id
        author
        title
        url
        content
        version
    }
}
`
</code></pre>

<p>Yet, even after I have implemented these changes, the file did not get uploaded...</p>
