scala-pet-store VS Http4s

Hello, you can try to look for pet store implementations on GitHub using Scala, like https://github.com/pauljamescleary/scala-pet-store. The "Pet Store" is usually an example repo demonstrating how to build a CRUD service. Since Scala is a language capable of expressing multiple design techniques, multiple ways of solving similar problems exist, which is neither good nor bad, just irritating for a beginner.

- https://github.com/pauljamescleary/scala-pet-store

Hi guys, finish you know of any good github sample apps, written in scala, in proper functional style ? the ⠀goal is to see actual production code that is FP worthy, to look up to :) I am looking to see how FP looks in practice similar to https://github.com/pauljamescleary/scala-pet-store or https://github.com/hcwilhelm/twm I have 2 years of scala experience, mostly akka tech stack, and some basic cats knowledge. Thanks Mircea

https://github.com/pauljamescleary/scala-pet-store My case is the first one. I've been working with scala for a while using Akka actors, Akka http and Play and I would like to see the FP scala concept and its libraries working in a real project.

I learned a lot from this project. It's not a tutorial or a lib. It's a fully functional yet simple project: https://github.com/pauljamescleary/scala-pet-store.

One sample app using DDD I like is the Scala Pet Store.

If you want a mature REST API library, I recommend http4s. Be aware, though, that it’s based on purely-functional programming with Cats, cats-effect, and fs2, so if you’re not familiar with them or aren’t prepared to commit to the paradigm, the learning curve may be daunting, seem pointless, or both.

See also cats-effect and fs2. cats-effect gives you your IO Monad (and IOApp to run it with on supported platforms). fs2 is the ecosystem’s streaming library, which is much more pervasive in functional Scala than in Haskell. For example, http4s and Doobie are both based on fs2.

Most important/known: * https://http4s.org/ - an HTTP client/server * https://github.com/typelevel/fs2 - streaming * https://github.com/tpolecat/doobie - JDBC

Scala devs are too busy wondering about free monads and F[Request[F] => Response[F]]. I am very pleased by http4s, Doobie, ScalaJS, and the whole ecosystem, really: https://http4s.org

In reality, your performance issues will not be http4s, but something else. That being said, there are improvements that http4s can and is making, and I'm quite excited about the future 1.0 release, which has some important and fundamental performance improvements already, like a a 125% performance improvement on the plaintext benchmark from https://github.com/http4s/http4s/pull/6091 - and finally, yes, akka-http does have very good performance, but you can also get good performance out of http4s.

http4s for REST services.

This is a long list of misunderstandings I don’t have the patience to unpack. Instead, let me refer you to the links in my top comment in the thread, then suggest you learn at least http4s, a purely-functional web service library that’s been used in production for a decade or so now.

I would say http4s and Doobie. Both are pure FP libraries in the Typelevel ecosystem. Both are exceptionally clear, extremely reliable, extremely pleasant to use… I like to point out http4s, in particular, is primarily a collection of types modeling the relevant RFCs. What behavior it has comes overwhelmingly from the underlying Cats, cats-effect, and fs2 libraries. This reflects the generality of those underlying libraries and the intense focus of the http4s team. The same applies to Rob Norris and Doobie, which tames JDBC as well as it can be tamed, IMO.

The most popular nowadays are - I guess - akka-http and http4s. You can also use Play if you don't want to start from scratch but prefer a framework-based approach.

If you want something more powerful, pure-functional and you need to do complex, concurrency-heavy operations, have a look at http4s: https://http4s.org/