utility-belt

Although seemingly unremarkable in appearance, the utility belt is one of Batman's most important tools in fighting crime.

About

Utility belt has a limited functionality: it only provides commonly used functions wrapping a limited set of dependencies.

Currently it has:

• utility-belt.id - various functions for working with UUIDs
• utility-belt.json - sets up automatic conversions of Joda time objects to/from JSON, you need to pull in clj-time and cheshire if you need to use those
• utility-belt.time - common functions for date and time calculations, you need to pull in clj-time if you need to use those
• utilit-belt.conv - type conversions (string to int, int to string, etc)
• utlity-belt.component - small utils which make working with Stuart Sierra's Component a bit easier
• utility-belt.map-keys - easy transformations of map keys between kebab and snake case
• utility-belt.lifecycle - helpers to manage Clojure application lifecycle (registering shutdown hooks etc)
• utility-belt.debug - helpers for debugging code, mostly locally

nREPL component

Micro wrapper around nREPL server, as easy to use as passing the port number.

:warning: This is a REPL so take care of securing it!

(def system
  {:nrepl-server (utility-belt.component.nrepl/create 23211)})

:raising_hand: Note that the server by default binds to 0.0.0.0

You can pass the address to bind to if you need more control:

(def system
  {:nrepl-server (utility-belt.component.nrepl/create 23211"127.0.0.1")})

Lifecycle hooks

utility-belt.lifecycle provides a set of helpers to manage application lifecycle. Best used if you're using Component. The use case is to add graceful shutdown capabilities to long lived applications, and handle things such as stopping the component system during application shutdown.

Example:

(ns app.core
  (:require [app.system]
            [com.stuartsierra.component :as component]
            [utility-belt.lifecycle :as life]))

(def system (atom nil))

(def -main []
  (life/register-shutdown-hook :stop-system #(component/stop @system))
  (life/register-shutdown-hook :goodbye #(println "BYYYYEEEE 👋"))
  (life/install-shutdown-hooks!)
  (reset! system (component/start (app.system/create))))

Authors

^{In alphabetical order}

• Afonso Tsukamoto
• Łukasz Korecki
• Marketa Adamova