DownloadThreadIDs.py

import time
import requests
from math import floor
from urllib.parse import urlencode

auth_token = input('Enter your authorization token: ')
channel_id = input('Enter the forum channel ID: ')

base = f'https://discord.com/api/v9/channels/{channel_id.strip()}/threads/search?'
params = {
    # 'archived': False,
    'sort_by': 'last_message_time',
    'sort_order': 'desc',
    'limit': 25,
    'tag_setting': 'match_some',
    'offset': 0
}

s = requests.Session()
s.headers = { 'Authorization': auth_token.strip() }

thread_count = None
thread_ids = []

while True:
    res = s.get(base+urlencode(params))
    if res.status_code == 200:
        data = res.json()
        
        for thread in data['threads']:
            if thread['id'] not in thread_ids:
                thread_ids.append(thread['id'])
            else:
                print(f'Skip {thread["id"]} - seen already')

        if thread_count == None:
            thread_count = data['total_results']
            print('Total threads:', thread_count)
        if data['has_more'] == False:
            break
        else:
            params['offset'] += 25
    else:
        print(f'Error {res.status_code}: {res.json()["message"]}')
        break

threads_retrieved = len(thread_ids)
if threads_retrieved == 0:
    print('Target channel does not have any threads.')
else:
    with open(f'threads_{channel_id}_{floor(time.time())}.txt', 'w') as f:
        f.write('\n'.join(thread_ids))
        f.close()
    print(f'Threads retrieved for channel {channel_id}. Total: {threads_retrieved}')