Rest API File management with aldeed simple-schema

I’m building a Rest API using Meteor. Now I’m trying to setup an images file transfer in the API. My schema is defined with node simpl-schema. I have a collection called Post with some basic fields (title, content). My goal is to add a third field (images) so that a Post will have a title, content, and image.
I found out that one could use ostrio:files but with simple-schema (not node simpl-schema) to achieve this. How can I implement HTTP Rest methods like PUT, GET… using these package?
A basic idea would be to convert these images files or URL into base64 and then save output in a simple schema String field. But my knowledge in Meteor File System is really poor at the moment.