apollo graphql query an uploaded file

Apollo Server 2.0 has the ability to receive file uploads as described in this blog post.

However, all the tutorials and blog posts I found only showed how to upload a file. Nobody demonstrated how to actually retrieve the file back to display it onscreen.

Does anybody know how to properly query the file contents for display onscreen?
Also, there's the possibility that maybe there is no way of querying a file and you have to build a separate rest endpoint to retrieve the contents?

Some thoughts:
I imagine the query to be something like

query {
  fetchImage(id: 'someid')
}

with the respective server-side definition

type Query {
  fetchImage(id : ID!): Upload //maybe also a custom type, but how do I include the actual file contents?
}

Hint: Upload is a scalar type that apollo-server automatically adds to your type definition. It is used for the upload so I imaging it also being usable for the download/query. Please read the blog post mentioned above for more information.

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