Encrypted is a simple monadic data type that wraps arbitrary data for asymmetric encryption. It provides map and flatMap functions to apply operations on the payload.

First you need to generate key pairs for all involved parties:

import com.github.greywombat.encrypted._

val alice = KeyPair("alice")
val bob = KeyPair("bob")
val eve = KeyPair("eve")

Then, you can set up a key store for the public keys of all members and declare one private key as your own:

implicit val publicKeyStore: PublicKeyStore = KeyStore().addKey(alice).addKey(bob).addKey(eve)
implicit val privateKey: PrivateKey = alice

Afterwards you can use it:

val enc: Encrypted[String] = Encrypted("Secret data")

Note that it is not actually encrypted yet, to do

val enc = Encrypted("Secret data").encrypt

To limit access to the data, you can apply a set of client ids:

val enc = Encrypted("Secret data").restrict(Set("alice", "bob")).encrypt

You can access the payload by calling get (optionally with a private key):

// Some("Secret data")
enc.get

// None
enc.get(eve.privateKey)

Encrypted values can be mapped over:

// Some("Secret data. And more secret data.")
enc.map(_ + ". And more secred data.").get

Or, used in a list comprehension:

val enc2 = for(
    a <- enc;
    b <- Encrypted(". And more secret data.").restrict(Set("alice"))
  ) yield a + b

// Some("Secret data. And more secret data.")
enc2.get

// None
enc2.get(bob)

When doing this the resulting encrypted container only allows access for parties that have access to all data that was involved in creating the new data.