main.py

from typing import List
import urllib
import requests
from codecs import open
import os
import multiprocess as mp

if not os.path.exists('./results'):
  os.makedirs('./results')

attempts = 0
fails = 0
namespace = [str(i) for i in range(10)] + [chr(i) for i in range(97, 123)]
start_value = "c11912"
current_value = start_value
max_value = "1qvc8ny"
url_template = "https://prnt.sc/"
headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:77.0) Gecko/20100101 Firefox/77.0'}
search_string = '<meta property="og:image" content="'
end_string = '"/>'

def to_namespace(value: str) -> List[int]:
  return [namespace.index(x) for x in value]

def to_str(value: List[int]) -> str:
  return "".join([namespace[i] for i in value])

def get_next(value: str) -> str:
  ns = to_namespace(value)
  pos = -1
  while (ns[pos] + 1) % 36 == 0:
    ns[pos] = 0
    pos -= 1
  ns[pos] += 1
  return to_str(ns)

def save_image(value: str) -> bool:
  print(f"Attempt {value}")
  req = urllib.request.Request(url_template + value, headers=headers)
  data = urllib.request.urlopen(req).read()
  sdata = data.decode('utf-8')

  start = sdata.find(search_string) + len(search_string)
  if start == -1:
    return True
  end = sdata.find(end_string, start)
  
  url = sdata[start:end]

  img = requests.get(url)
  if img.status_code != 200:
    return True
  
  img = img.content
  
  img_format = url.split(".")[-1]
  with open(f"./results/{value}.{img_format}", "wb") as fh:
    fh.write(img)
    fh.close()

  return False

if __name__ == '__main__':
  elements = [current_value]
  while len(elements) < 100:
    current_value = get_next(current_value)
    elements += [current_value]
  
  pool = mp.Pool(5)
  results = pool.map(save_image, elements)

  print(f"Attempts: {len(results)}")
  print(f"Failures: {len(list(filter(lambda x: x, results)))}")
  print(f"Success rate: {(len(results) - len(list(filter(lambda x: x, results)))) / len(results)}")