clojuREST

A minimal REST API written in Clojure

Unlike most Clojure backend projects, clojuREST only uses one 3rd party library to set up a web server with routing. Typically you see a lot of projects using Ring and Compojure which are great and really streamline server development but they introduce a lot of dependencies. clojuREST gets around this by using http-kit. You have to write a little extra code but in return you get more control over data flow.

Disclaimer

clojuREST is not a library, nor does it have any use as standalone software. It’s merely a proof of concept that someone may use to create an API with minimal dependencies. Feel free to download and modify as needed.

Services

By default, http-kit starts a server at localhost:8090. Aside from the index /(which returns Hello, World!), there are two built-in web services:

1. Test

   • endpoint: /test
   • supported methods: any
   • accepted body: any
   • prints testing to the commandline
   • used for verifying other services (which may fail if written incorrectly)

2. Secret

   • endpoint: /secret
   • supported methods: GET, PUT
   • accepted body: any JSON-formatted data
   • reads/writes the file “secret”
   • a crude example of a stateful service

These are handled by the functions test-service and secret-service respectively.

Functions

In addition to the services, there are two other functions in core.clj:

1. respond

   • takes an optional body to return in an HTTP response
   • prints the body to the commandline
   • returns the body, HTTP status 200, and some headers used by cljs-ajax(another minimalist library I use)

2. handler

   • a callback used by the http-kit server
   • captures the received request in the parameter request
   • parses the body using clojure.data.json/read-str
   • handles routing with nested case expressions

Building

1. Get Leiningen
2. cd to project directory
3. lein uberjar - this will create two jars:
   • clojurest-0.0.1.jar - smaller, but only runs on the build computer
   • clojurest-0.0.1-standalone.jar - larger, but works on any computer

Running

• Run with Leiningen (in project directory): lein run
• Run with Java: java -jar clojurest-0.0.1-standalone.jar

*you may need admin privileges to allow the application through your firewall