Guest user posting content that is later retrieved by registered user

Hi,

Is there a way that a registered user could send an ‘invite’ link to a guest user, who could then follow that URL to the Meteor app, post some content, and then have that content retrievable by the registered user?

Specifically I’d like to use the Slingshot package and have files uploaded to S3. I’m thinking something along the lines of having that URL contain some unique ID that could be posted as metadata to S3, which the registered user would also be able to access?

I’m thinking really high level here but just wondered if this is something anyone has done before.

Thanks!