Http4s
cats
Our great sponsors
Http4s | cats | |
---|---|---|
24 | 43 | |
2,509 | 5,171 | |
0.6% | 0.8% | |
9.8 | 8.9 | |
1 day ago | 5 days ago | |
Scala | Scala | |
Apache License 2.0 | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
Http4s
-
How to get started?
http4s is a Typelevel project, and therefore falls into the "program in Scala as if it were Haskell" category. Many people find this off-putting, but honestly, I think with the resources listed above, this is the option at the best intersection of "mature" and "well-documented" available in Scala. The reason it's off-putting to many people is that Haskell-style pure FP isn't mainstream, so it isn't so much a matter of learning a new technology as it is a matter of learning a new paradigm, which necessarily means surfacing and unlearning things you already know, and perhaps confronting the uncomfortable feeling that things you thought were "fundamental," "have to be that way," aren't, and don't. I personally found this process liberating. But not everyone does.
-
Server Stack Options for Scala
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.
-
Sequential application of a constructor?
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.
-
Grasping the concepts and getting them down to earth
Most important/known: * https://http4s.org/ - an HTTP client/server * https://github.com/typelevel/fs2 - streaming * https://github.com/tpolecat/doobie - JDBC
-
Relative popularity of programming languages on Hacker News
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
-
http4s as a replacement for akka-http?
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.
-
Is Scala a good choice for a data intensive web backend?
http4s for REST services.
-
Scala became Typelevel/Zio only ecosystem?
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.
-
Pleasant to use Scala libraries
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.
-
Why do all frameworks use OOP? (php)
There are functional frameworks: https://http4s.org/
cats
-
Beware of teammates who refactor code based on personal taste without proper documentation or completeness. Sounds familiar.
A functional programming library: https://typelevel.org/cats/
-
Is Scala worth learning in 2023?
Learn something that pays the bill first - nowadays it's Golang/Rust react/typescript. Then you can try some pure fp libs like fp-ts and fp-core.rs, and look through existing scala cats docs. If you'll feel bad about it - that's totally fine and expectable, fp takes a paradigm shift and not that many dev able to shift their brains way of thought due to basic psychological rigidity) (inability to change habits and to modify concepts/attitudes once developed). And that's purely a staffing and management issue - folks hired randoms out of the blue, and called 'em a team.
-
Going into year 2 of Software Development Foundation Degree, have a particular liking for OOP and SQL, any tips, info or pointers on where to go from there?
I'm sorry, but have you ever done functional programming for a real company, like in a functional programming language like Haskell, Scala, or F#? Have you ever used Scala cats or scalaz? Have you ever learned category theory and how to apply its abstractions in software? Listen u/judethedude2106 this person hasn't gone as far down the functional programming rabbit hole as I have. Beyond learning the basics like the difference between pure and impure functions, what are closures, what higher order functions are and the most common ones like .map, .filter, and .flatmap, the immutable collections like immutable linked lists and trees, and what a Monad is and common monads like those used for futures/promises, async programming, and Option (Some or None, which is used instead of null checking), the more advanced functional programming stuff like category theory based abstractions are totally useless for real jobs and is just a giant time suck. Don't waste years on functional programming, spend at most a few months on it and no more.
-
rsmonad: Monads in stable Rust (+ Applicative, Alternative, Functor, Monoid, ...)
As a former functional programmer in Scala, please do not go deep into the Category Theory programming. Scala has libraries like this one called "Cats", a cute shortened name for "Category Theory", but code that makes heavy use of these constructs is not understandable to other programmers. Other than using Monads as a design pattern for things like Options (which can be "Some" or "None"), Futures or Promises (which is used for asynchronous programming), and a few other things, please do not make heavy use of category theory constructs in real programming projects that will have other developers working on them. It is a rabbit hole that may be fun but is not super practical. Sure, write pure functions without side effects, but do not use the words "Bimonad", "Invariant Monoidal", and "Semigroup" in your code. The most common, practical application/use of functional programming is basic things like closures, .map, .filter, maybe chaining maps with like a .flatmap or whatever your programming language uses instead of chain or flatmap, and SQL that uses keywords like WHERE which can be represented in code by using a call to .filter. Like the place where these constructs are used most is in data processing like with SQL, ETL (Extract Transform, Load) jobs, Java's MapReduce on Hadoop, Scala's Apache Spark, and other data processing type things. Haskell is not a popular programming language in real world projects for a number of reasons and one of them is the heavy and sometimes impractical use of Category Theory.
-
Tmux, NeoVim, etc. to write pure Kotlin code?
At a previous job of mine we actually had an entirely pure Scala ecosystem using cats which instead uses typeclasses, referential transparency, and other FP concepts as the foundations for how to code. So a lot of flexibility to the language.
-
[E => *] Type
Thanks! It's used heavily here
- for comprehension and some questions
-
Ask HN: How has functional programming influenced your thinking?
I did work in Scala for a few years. We employed Cats[1], and even a bit of Matryoshka[2] though most of the work I do today is in Python.
Nowadays I think about computational requirements in terms of relations among behavioral dependencies. Like, "I want to perform operation O on input A and return a B. To do this, I'll need a way to a -> b and a way to b -> b -> b." I often pass these behavioral dependencies in as arguments and it tends to make the inner core of my programs pretty abstract and built up as layers of specificity.
Zooming out nearly all the way, it makes me feel tethered in a qualitatively unique way to certain deep truths of the universe. In a Platonic sense, invoking certain ideas like a monad make me feel like I'm approaching the divine or at least one instantiation of a timeless universal that operates outside of material existence.
I'd imagine some mathematicians might see the universe in a similar way - one where immortal relations between ontological forms exist beyond time and space and at the same time can be threaded through the material world by intellectual observation and when those two meet a beautiful collision occurs.
1. https://typelevel.org/cats/
2. https://github.com/precog/matryoshka
-
yet another post about type classes in Scala
Our second type class example attempted to illustrate one last perk: type safety at compile time. It did so with a simplified example of the cats core library for type safety equality comparison between objects. If you're not familiar with cats, go ahead and give it go.
- What are the design principles of Cargo?
What are some alternatives?
Akka HTTP - The Streaming-first HTTP server/module of Akka
Scalaz - Principled Functional Programming in Scala
sttp - The Scala HTTP client you always wanted!
Shapeless - Generic programming for Scala
ZIO - ZIO — A type-safe, composable library for async and concurrent programming in Scala
Finch.io - Scala combinator library for building Finagle HTTP services
ScalaTest - A testing tool for Scala and Java developers
zio-http - A next-generation Scala framework for building scalable, correct, and efficient HTTP clients and servers
Monocle - Optics library for Scala
Spray - A suite of scala libraries for building and consuming RESTful web services on top of Akka: lightweight, asynchronous, non-blocking, actor-based, testable
Scala Async - An asynchronous programming facility for Scala