youtubedl-gui.py

from queue import Empty, Queue
import subprocess
import sys
import threading

if sys.version[0] > '2':
    import tkinter
else:
    import Tkinter as tkinter

out_queue = Queue()


def dwnl(_):
    url = url_input.get()
    url_input.delete(0, 'end')
    proc = subprocess.Popen(['youtube-dl.exe', '-t', url], stdout=subprocess.PIPE)

    def poll():
        result = b''
        while 1:
            char = proc.stdout.read(1)
            if not char:
                out_queue.put(result)
                break
            result += char
            if char == b'\r':
                out_queue.put(result)
                result = b''

    t = threading.Thread(target=poll)
    t.start()

    def update():
        root.after(20, update)
        try:
            line = out_queue.get_nowait().decode('utf8').rstrip()
        except Empty:
            return
        if not line:
            return

        if line[0] != '\n':
            output.delete('end-1l linestart', 'end')
            line = '\n' + line

        output.insert('end', line)

    update()


root = tkinter.Tk()

url_input = tkinter.Entry(root)
url_input.pack(expand=0, fill='x')
url_input.bind('<Return>', dwnl)

output = tkinter.Text(root)
output.pack(expand=1, fill='both')
output['bg'] = 'black'
output['fg'] = 'white'

root.mainloop()