import os
import re
import sys
import time
from typing import Optional
import httpx
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.chrome.service import Service
from webdriver_manager.chrome import ChromeDriverManager
from dotenv import load_dotenv
load_dotenv()
BASE_URL = "https://flexstudent.nu.edu.pk"
def _log(msg: str):
print(msg, file=sys.stderr)
def _find_chrome_binary() -> Optional[str]:
"""Find Chrome binary path on Windows."""
if sys.platform != "win32":
return None # Let Selenium find it on other platforms
# Common Chrome installation paths on Windows
possible_paths = [
os.path.expandvars(r"%ProgramFiles%\Google\Chrome\Application\chrome.exe"),
os.path.expandvars(r"%ProgramFiles(x86)%\Google\Chrome\Application\chrome.exe"),
os.path.expandvars(r"%LocalAppData%\Google\Chrome\Application\chrome.exe"),
r"C:\Program Files\Google\Chrome\Application\chrome.exe",
r"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe",
]
for path in possible_paths:
if os.path.exists(path):
_log(f"Found Chrome at: {path}")
return path
return None
class FlexSession:
def __init__(self):
self.client: Optional[httpx.Client] = None
self.cookies: dict = {}
self.page_dumps: dict = {}
self._logged_in = False
def login(self) -> bool:
roll_no = os.getenv("FLEX_ROLL_NO")
password = os.getenv("FLEX_PASSWORD")
if not roll_no or not password:
raise ValueError("FLEX_ROLL_NO and FLEX_PASSWORD must be set in environment")
options = webdriver.ChromeOptions()
options.add_argument("--start-maximized")
options.add_argument("--log-level=3")
options.add_experimental_option("excludeSwitches", ["enable-automation", "enable-logging"])
options.add_experimental_option("useAutomationExtension", False)
chrome_path = _find_chrome_binary()
if chrome_path:
options.binary_location = chrome_path
os.environ['WDM_LOG_LEVEL'] = '0'
driver = webdriver.Chrome(
service=Service(ChromeDriverManager().install()),
options=options
)
try:
driver.get(f"{BASE_URL}/Login")
WebDriverWait(driver, 10).until(
EC.presence_of_element_located((By.ID, "m_inputmask_4"))
)
username_field = driver.find_element(By.ID, "m_inputmask_4")
password_field = driver.find_element(By.ID, "pass")
username_field.clear()
username_field.send_keys(roll_no)
password_field.clear()
password_field.send_keys(password)
time.sleep(2)
recaptcha_iframe = WebDriverWait(driver, 10).until(
EC.presence_of_element_located((By.CSS_SELECTOR, "iframe[src*='recaptcha']"))
)
driver.switch_to.frame(recaptcha_iframe)
checkbox = WebDriverWait(driver, 10).until(
EC.element_to_be_clickable((By.CSS_SELECTOR, ".recaptcha-checkbox-border"))
)
checkbox.click()
driver.switch_to.default_content()
# Wait for CAPTCHA to be solved (either auto-pass or human solves image challenge)
_log("Waiting for CAPTCHA to be solved...")
_log("If an image challenge appears, please solve it manually.")
captcha_timeout = 120 # 2 minutes for human to solve if needed
captcha_solved = False
start_time = time.time()
while time.time() - start_time < captcha_timeout:
try:
# Check if g-recaptcha-response has a value (means CAPTCHA is solved)
recaptcha_response = driver.execute_script(
"return document.getElementById('g-recaptcha-response')?.value || '';"
)
if recaptcha_response:
_log("CAPTCHA solved successfully!")
captcha_solved = True
break
except Exception:
pass
time.sleep(1)
if not captcha_solved:
raise Exception("CAPTCHA was not solved within the timeout period")
sign_in_button = WebDriverWait(driver, 10).until(
EC.element_to_be_clickable((By.ID, "m_login_signin_submit"))
)
sign_in_button.click()
WebDriverWait(driver, 30).until(
lambda d: "/Login" not in d.current_url
)
page_source = driver.page_source
dump_links = re.findall(r'href="(/[^"]*\?[^"]*dump=([^"&]+)[^"]*)"', page_source)
for full_url, dump_value in dump_links:
path = re.sub(r'\?.*', '', full_url)
self.page_dumps[path] = dump_value
dump_patterns = re.findall(r'(/[A-Za-z][^"\'?]*)\?[^"\']*dump=([^"\'&]+)', page_source)
for path, dump_value in dump_patterns:
if path not in self.page_dumps:
self.page_dumps[path] = dump_value
selenium_cookies = driver.get_cookies()
for cookie in selenium_cookies:
self.cookies[cookie["name"]] = cookie["value"]
self.client = httpx.Client(
base_url=BASE_URL,
cookies=self.cookies,
headers={
"User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36"
},
follow_redirects=True,
timeout=30.0
)
self._logged_in = True
return True
except Exception as e:
_log(f"Login error: {e}")
return False
finally:
driver.quit()
def get(self, path: str) -> httpx.Response:
if not self._logged_in or not self.client:
raise RuntimeError("Not logged in. Call login() first.")
return self.client.get(path)
def get_html(self, path: str, append_dump: bool = True) -> str:
if append_dump and "dump=" not in path:
base_path = path.split("?")[0]
dump_token = self.page_dumps.get(base_path)
if dump_token:
separator = "&" if "?" in path else "?"
path = f"{path}{separator}dump={dump_token}"
response = self.get(path)
response.raise_for_status()
return response.text
def is_logged_in(self) -> bool:
return self._logged_in
def close(self):
if self.client:
self.client.close()
_session: Optional[FlexSession] = None
def get_session() -> FlexSession:
global _session
if _session is None:
_session = FlexSession()
return _session
def ensure_logged_in() -> FlexSession:
session = get_session()
if not session.is_logged_in():
if not session.login():
raise RuntimeError("Failed to login to FLEX portal")
return session
