Introduction

This Scala library allows to fetch nested data like

Book(
  "book-1",
  "The Design of Everyday Things",
  Author(
    "author-1",
    "Donald Norman"
  )
)

from a number of endpoints, local or remote.

You might wonder why you would need such a library... Well, here is a simple case where this really gets out of hand fast:

• 2 remote databases with books: XML and JSON
• 1 remote database with authors
• 1 local database with authors (try first!)
• authors have avatars stored in Amazon S3
• avatar cache (try first!)
• download things in batches, but
• never download the same thing twice

And, finally, all we want is a function needBook(id: String): Future[Book] that takes care of all this.

If this sounds like your problem, proceed to the tutorial.