a script to download photos from Pixelfed data export JSON file

pixelfed-images.cljs

#!/usr/bin/env lumo
(ns pixelfed-images.core
  (:require
   [clojure.walk :refer [prewalk]]
   [cljs.core :refer [*command-line-args*]]
   [clojure.string :as string]))

(def fs (js/require "fs"))
(def https (js/require "https"))
(def stream (.-Transform (js/require "stream")))

(defn download-media [url filename]
  (https.get url
           (fn [resp]
             (let [data (stream.)]
               (.on resp "data"
                    (fn [chunk]
                      (.push data chunk)))
               (.on resp "end"
                    (fn []
                      (fs.writeFileSync filename (.read data))))
               (.on resp "error"
                    (fn [error]
                      (js/console.log error)))))))

(defn parse-data [filename]
  (let [data (-> (fs.readFileSync filename "utf8") js/JSON.parse)]
    (doseq [item data]
      (doseq [attachment (.-attachment item)]
        (when attachment
          (let [url (.-url attachment)
                filename (last (string/split url #"/"))]
            (when-not (fs.existsSync filename)
              (js/console.log (str "downloading: " filename))
              (download-media url filename))))))))

(-> (.-argv js/process) last parse-data)

;; Usage

;; install Lumo (https://github.com/anmonteiro/lumo): npx -p lumo-cljs lumo
;; download statuses from the Pixelfed Data Export menu, the file will be called outbox.json
;; run: lumo pixelfed-images.cljs outbox.json

Won't work if outbox.json cannot be generated because Pixelfed does not manage yet more than 500 statuses :(