Example of a simple webapp written as a single file

README.md

Instructions

0. Get Boot
1. Copy the above file to $HOME/app.boot
2. $ chmod a+x $HOME/app.boot
3. $ cd && ./app.boot

app.boot

#!/usr/bin/env boot

(print "Loading dependencies... ")
(set-env! :dependencies '[[pandeiro/agua "0.1.0"]])
(require '[agua.core :refer [defhtml defcss defcljs serve]])
(println "done.")

;;
;; HTML page: expects three %s for css, prerendered html and js
;;
(defhtml page
  [:head
   [:meta {:charset "utf-8"}]
   [:title "My App"]
   [:style "%s"]]
  [:body
   [:div#root "%s"]
   [:footer "Copyright 2015 you"]
   [:script "%s"]])

;;
;; CSS
;;
(defcss styles
  [:*
   {:box-sizing "border-box"}]
  [:body
   {:padding    "36px"
    :background "black"
    :color      "lightgray"
    :text-align "center"}]
  [:h1
   {:color "white"}]
  [:input
   {:font-size  "24px"
    :background "rgb(20,20,20)"
    :border     "solid 1px white"
    :font-style "italic"
    :padding    "12px"
    :color      "rgb(150,150,150)"
    :border-radius "8px"}]
  [:footer
   {:position    "fixed"
    :bottom      0
    :left        0
    :width       "100%"
    :padding     "8px"
    :font-family "monospace"}])

;;
;; ClojureScript
;;
(defcljs app
  (ns app.core
    (:require [reagent.core :as r]))

  (def state
    (r/atom
     {:person "person"}))

  (defn- person-val [e]
    (or (not-empty (.-value (.-target e))) "person"))

  (defn main [state]
    [:div
     [:h1 (str "Hello, " (:person @state))]
     (when js/document
       [:input
        {:placeholder "Name, please"
         :on-change #(swap! state assoc :person (person-val %))}])])

  (defn not-found []
    [:div
     [:h1 (str "404: '" js/location.pathname "' wasn't found.")]])

  (defn router []
    (condp re-find js/location.pathname
      #"^/$" [main state]
      [not-found]))

  (if js/document
    (r/render [router] (.getElementById js/document "root"))
    (r/render-to-string [router])))


(defn -main [& args]
  (serve {:html page, :css styles, :app app}))

This is so sexy 👍