Where to put `-main` and how to call it with Integrant

Questions & Help How to?
2

I plan to describe the exact process on my blog soon. But here are some code snippets:

I’ve a core namespace with:

(ns com.example.core
  (:require [com.example.system :as system]))

(defn -main [& _args]
  (system/start :dev))

It just starts the system:

(ns com.example.system
  (:require [integrant.core :as ig]))

;; read it using juxt/aero for example
(def config {})

(defn start [profile]
  (ig/init config))

And that’s all.

I’ve a separate namespace user to run integrant-repl:

(ns user
  (:require [clojure.tools.namespace.repl :refer [set-refresh-dirs]]
            [clojure.java.classpath :refer [classpath-directories]]
            [integrant.repl :as ig-repl :refer [clear go halt prep init reset reset-all]]
            [com.example.system :as system]))

(let [target-dir? (fn [f]
                    ;; match target, target/dev target/prod, etc.
                    (re-matches #".*target(/\w+)?" (str f)))]
  (apply set-refresh-dirs
    (remove target-dir? (classpath-directories))))

(ig-repl/set-prep! (constantly (system/config))

I don’t use rebel. I run the app with clojure -m com.example.core and the REPL with some aliases like clojure -A:dev:repl.

I hope it helps.

Also. If you need something with batteries included you can try out juxt/edge :slight_smile:

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