initiating python script with arguments from another script, setting argparse values programatically

Question

i was using a python package (spotify_dl) to genereate some files. i was doing it manually through the command line: spotify_dl -l spotify_playlist_link -o download_directory

now i want to do it from inside another python script.

i looked at the package code and found the main function, but i can't figure how to run the main function with arguments of my choosing - in python.

for example what i want:

from spotify_dl import spotify_dl as sp_dl

if __name__=='__main__':
    destination_dir = r'D:\some\folder\path'
    playlists_url = ['url1','url2','url3',....]

    for url in playlists_url:
        sp_dl.spotify_dl(l=url,o=destination_dir)

for better clarity, here is the actual code of the spotify_dl main function:

#!/usr/bin/env python
import argparse
import json
import os
import sys
from logging import DEBUG
from pathlib import Path, PurePath

import spotipy
from spotipy.oauth2 import SpotifyClientCredentials

from spotify_dl.constants import VERSION
from spotify_dl.models import db, Song
from spotify_dl.scaffold import log, check_for_tokens
from spotify_dl.spotify import fetch_tracks, parse_spotify_url, validate_spotify_url, get_item_name
from spotify_dl.youtube import download_songs, default_filename, playlist_num_filename


def spotify_dl():
    """Main entry point of the script."""
    parser = argparse.ArgumentParser(prog='spotify_dl')
    parser.add_argument('-l', '--url', action="store",
                        help="Spotify Playlist link URL", type=str, required=True)
    parser.add_argument('-o', '--output', type=str, action='store',
                        help='Specify download directory.', required=True)
    parser.add_argument('-d', '--download', action='store_true',
                        help='Download using youtube-dl', default=True)
    parser.add_argument('-f', '--format_str', type=str, action='store',
                        help='Specify youtube-dl format string.',
                        default='bestaudio/best')
    parser.add_argument('-k', '--keep_playlist_order', default=False,
                        action='store_true',
                        help='Whether to keep original playlist ordering or not.')
    parser.add_argument('-m', '--skip_mp3', action='store_true',
                        help='Don\'t convert downloaded songs to mp3')
    parser.add_argument('-s', '--scrape', action="store",
                        help="Use HTML Scraper for YouTube Search", default=True)
    parser.add_argument('-V', '--verbose', action='store_true',
                        help='Show more information on what''s happening.')
    parser.add_argument('-v', '--version', action='store_true',
                        help='Shows current version of the program')
    args = parser.parse_args()

    if args.version:
        print("spotify_dl v{}".format(VERSION))
        exit(0)

    db.connect()
    db.create_tables([Song])
    if os.path.isfile(os.path.expanduser('~/.spotify_dl_settings')):
        with open(os.path.expanduser('~/.spotify_dl_settings')) as file:
            config = json.loads(file.read())

        for key, value in config.items():
            if value and (value.lower() == 'true' or value.lower() == 't'):
                setattr(args, key, True)
            else:
                setattr(args, key, value)

    if args.verbose:
        log.setLevel(DEBUG)

    log.info('Starting spotify_dl')
    log.debug('Setting debug mode on spotify_dl')

    if not check_for_tokens():
        exit(1)

    sp = spotipy.Spotify(auth_manager=SpotifyClientCredentials())
    log.debug('Arguments: {}'.format(args))

    if args.url:
        valid_item = validate_spotify_url(args.url)

    if not valid_item:
        sys.exit(1)

    if args.output:
        item_type, item_id = parse_spotify_url(args.url)
        directory_name = get_item_name(sp, item_type, item_id)
        save_path = Path(PurePath.joinpath(Path(args.output), Path(directory_name)))
        save_path.mkdir(parents=True, exist_ok=True)
        log.info("Saving songs to: {}".format(directory_name))

    songs = fetch_tracks(sp, item_type, args.url)
    if args.download is True:
        file_name_f = default_filename
        if args.keep_playlist_order:
            file_name_f = playlist_num_filename

        download_songs(songs, save_path, args.format_str, args.skip_mp3, args.keep_playlist_order, file_name_f)


if __name__ == '__main__':
    spotify_dl()

so far i could see mentions of sys.argv but also some comments spoke against using that. what i want is a clear method that i could run in a loop without complications.

Balaïtous · Accepted Answer · 2021-06-30 21:55:27Z

2

spotify_dl is badly designed, I commonly use this:

def parse_args(argv=None):
    parser = argparse.ArgumentParser()
    ...
    return parser.parse_args(argv)

def main(args):
    # run your code

if __name__ == "__main__":
    args = parse_args()
    main(args)

Then you can import this first script in another and call the main function:

from my_first_script import main

def a_function():
    args = namedtuple("args", ("arg1", ...))("value1")
    main(args)

But you can workaround by overriding sys.argv:

if __name__=='__main__':
    destination_dir = r'D:\some\folder\path'
    playlists_url = ['url1','url2','url3',....]

    for url in playlists_url:
        sys.argv = [sys.executable, "-o", destination_dir, "-l", url]
        sp_dl.spotify_dl()

answered Jun 30, 2021 at 21:55

Balaïtous

9066 silver badges9 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

cmbfast · Accepted Answer · 2021-06-30 21:54:34Z

You can use subprocess here. I did not try your example because I don't have those libraries installed, but here's a simple example.

First, a simple commandline script called testpy.py has the following:

import sys
import argparse
def check_arg(args=None):
    parser = argparse.ArgumentParser(prog='Test',
                     description='Test',
                     epilog='Test')
    parser.add_argument('-f', '--first',
                        help='First argument',
                        required='True')
    results = parser.parse_args(args)
    return (results.first)



def main():
    with open('test.txt', 'a') as file:
        file.write('Success, {}\n'.format(f))


if __name__ == '__main__':
    f = check_arg(sys.argv[1:])
    main()

This takes one argument f and exports a text file (test.txt) with whatever argument was supplied.

This script can be run from a next script as (save this as new script file):

from subprocess import run, PIPE
args = ['python3', 'testpy.py', '-f', 'First input argument text']
res = run(args, stdout=PIPE, stderr=PIPE)

If you run this, you'll see that the file test.txt will be exported and calling the script testpy.py from this script was successful.

Collectives™ on Stack Overflow

initiating python script with arguments from another script, setting argparse values programatically

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related