如何用ClojureScript从pdf文件中创建一个字节矢量？

(ns my-app.core
  (:require [cljs.nodejs :as nodejs]
            [cljs.nodejs.fs :as fs]
            [cljsjs.pdfjs]))

(defn create-byte-vector-from-pdf [file]
  (let [buffer (fs/readFileSync file)
        pdf (.PDFDocument.)]
    (.then pdf (.getDocument pdf buffer))
    (.then pdf
           (fn [doc]
             (let [num-pages (.numPages doc)
                   page-promise (.getPage doc 1)]
               (.then page-promise
                      (fn [page]
                        (let [viewport (.getViewport page)
                              canvas (.createElement "canvas")
                              context (.getContext canvas "2d")]
                          (aset canvas "height" (.height viewport))
                          (aset canvas "width" (.width viewport))
                          (let [render-promise (.render page context viewport)]
                            (.then render-promise
                                   (fn [_]
                                     (let [data-url (.toDataURL canvas)]
                                       (-> data-url
                                           (.replace "data:image/png;base64," "")
                                           (.getBytes "base64")
                                           (js/Uint8Array.)
                                           (cljs.core/into [])))))))))))))

(defn -main []
  (let [pdf-file "path/to/pdf/file.pdf"
        byte-vector (create-byte-vector-from-pdf pdf-file)]
    (println byte-vector)))

(set! *main-cli-fn* -main)