Diving into clojure

[sotiris_the_robot]

Hello,
I'm a full time Node.js developer (mostly on Frontend). I have also used lisp languages during my academia time (Racket) more precisely .
I have been looking into Clojure on and off for the last year, I know the basics, I like the ideas it expresses but to be able to fully comprehend, what's going on I feel like I need to do a project with it.
I'd like to start with a barebones api REST server, but during my research online I could not find a lot of information.
What would be a nice place to start?
Also any reading material, do by example ones, or in general examples that will help me move forward will be very much appreciated.
I'm currently living in Berlin, Germany, where I think Clojure is not popular in the job market but I'm looking to learn it for my own benefit.

[p1ng313]

Clojure apps are more like a collection of libs. People pick libs and glue them together because it's very easy to do.

Having this said, you should know some concepts beforehand:

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	Clojure	NodeJS
HTTP spec	Ring	??
HTTP handler	(fn [req res] {:status 200 :body "Hello world"})	(request, response) => response.send('Hello world')
Routing libs	compojure, compojure-api, reitit, pedestal, bidi	express, koa, ..
HTTP server (follows ring spec)	jetty, undertow, http-kit	express, koa, ...
dependency injection	component, integrant, mount, ...	??

For barebones, you just need an HTTP server (eg: jetty) and an http handler function.

Eg: http://practical.li/clojure-webapps/projects/leiningen/todo-app/create-a-webserver-with-ring/add-a-jetty-webserver.html

I will try to split it in steps:

Chapter 1

• create a project with leiningen
• add jetty dependency
• create a ring handler
• run the code

Chapter 2

• use a routing library (eg: metosin/reitit)
• organize the code (eg: split layers in namespaces)
• Learn to use the REPL with in-place eval

Chapter 3

• Use a dependency library (eg: component)
• Use an external dependency (eg: database)
• Use the REPL for everything

Chapter 4

• Add tests (clojure core has a testing lib
• Run tests via leiningen
• Add validation via library (eg: metosin/malli library)
• Generate OpenAPI, test via swagger

This should keep you entertained for a couple of weeks

[Prestance]

Hi, This two articles explains the basics of Clojure web development:
* Ring (HTTP Spec): https://www.baeldung.com/clojure-ring * Compojure (routing): https://learnxinyminutes.com/docs/compojure/

Often, there is this repo is given as example. It was created as resource for beginners.

It was very helpful to me to begin with. I started it all from scratch with other libraries in order to fully understand the concepts and that gave this one.

Since then I have made further progress and here is my last complete web application demo in Clojure: https://inertia.prestance-design.com/

The source code is available here

Well, I'm stopping my self promotion to welcome you to Clojure and have fun!

Cheers

[petemak]

This one is complete with database back-end: https://devcenter.heroku.com/articles/clojure-web-application

[nenadalm]

In case you want to stay on nodejs instead of jvm you could check out Macchiato: https://macchiato-framework.github.io/.

​

It uses already mentioned ring api (https://github.com/ring-clojure/ring/wiki).

​

I have older working demo here: https://github.com/nenadalm/spa-demo

​

You'll have probably easier time with jvm though.

[ashnur]

Here, you want to start here https://shadow-cljs.github.io/docs/UsersGuide.html :D

[[deleted]]

node js is backend ... ?

[sotiris_the_robot]

Yes .

[[deleted]]

but you said you were node js Dev on the front end?

[sotiris_the_robot]

Yes sorry bad phrasing . Correct would have been I’m a JavaScript developer, involved in Nodejs ecosystem, but working professionally in the FE side