The Akka streams activator
provides a few illustrative examples. These are all based on the api, especially the Scala DSL; and
thus do not illustrate all the capabilities. (Quite reasonable given the very early stage of development).
The SPI provides a mechanism to unsubscribe, which lead to a question as to how that might actually be used.
The following code implements a Consumer that prints each line and unsubscribes when “TO” is encountered.
The Consumer is rather similar to the Reactive Extensions Observer.