Implementing the Pipes and Filters Pattern Using Actors in Akka for Java

This article is pretty silly. Why use Akka for this at all? You don't need an untyped distributed system just to chain functions together. For logically chaining functions together and accumulating errors, use Scalaz's \/:

http://eed3si9n.com/learning-scalaz/Either.html

    text >>= (t => if (containsForbiddenWord) { MyError.left[String] } else { t.right[MyError] })
         >>= latexToUnicode _ 
         >>= ...etc...

Unlike actors, this is deterministic and easily testable code.

If you really need to use a fancy concurrent system for this, Akka already has a built in piping/filtering framework called streams:

http://doc.akka.io/docs/akka/2.4.16/scala/stream/index.html

Unlike this actor example, streams comes with built in backpressure/concurrency handling.

For new code you should probably be using streams rather than akka actors.

This article is neat for learning about actors, but you should almost certainly not write production code this way.

I've been experimenting with pipe/filter architectures on and off for quite some time and so am very heartened to see renewed interest. In addition, I've heard a lot (mostly good) about Akka but haven't had a chance to actually work with it so this practical example is very welcome.

That said, the code I see seems very verbose, particularly the config part, for what amounts to:

   text-checker | latex2unicode | upload-to-s3 

In my own Objective-C based P/F implementation, I currently deal with pipes as arrays of filters, so it would be something like:

   [MPWPipe pipeWithFilters:@[ textChecker, latex2unicode, upload-to-s3 ]];

In Objective-Smalltalk, I'd think I can do better.

An overengineered solution for a trivial problem. All you'd need is 3 functions. No reason at all to use Akka.