Start Clojure Socket REPL server and write the port number into .repl-port

README.md

In your ~/.clojure/deps.edn, add an alias like this:

:socket {:extra-deps {jlmr/socket {:git/url "https://gist.github.com/jelmerderonde/c4a466563c703e856bd128d7982f48b3"
                                   :sha "81d80c5ebec3f2240eaf82a6d6e26eee93da4c6a"}}
         :exec-fn socket/start-server
         :exec-args {:name "server"
                     :port 0
                     :accept clojure.core.server/repl
                     :server-daemon false}}

Then, on the command line, run:

$ clojure -X:socket

deps.edn

{:paths ["."]}

socket.clj

(ns socket
  (:require
   [clojure.core.server :as server]
   [clojure.java.io :as io]))

(defn start-server
  [opts]
  (let [server (server/start-server opts)
        port (.getLocalPort server)
        host (-> server .getInetAddress .getCanonicalHostName)
        port-file (io/file ".repl-port")]
    (.deleteOnExit port-file)
    (spit port-file port)
    (printf "Socket server listening on %s:%s\n" host port)))