From ded70d1c71febb72e7b6afb7f41dcdaaa9594100 Mon Sep 17 00:00:00 2001
From: DerGrumpf <p.keier@beyerstedt-it.de>
Date: Mon, 15 Sep 2025 21:55:33 +0200
Subject: [PATCH] Fixed: CORS Error by providing user server with necessary
 policies, also removed dead code

---
 jupyterhub/jupyterhub_config.py | 86 +++++----------------------------
 1 file changed, 11 insertions(+), 75 deletions(-)

diff --git a/jupyterhub/jupyterhub_config.py b/jupyterhub/jupyterhub_config.py
index 5396880..2252c8d 100644
--- a/jupyterhub/jupyterhub_config.py
+++ b/jupyterhub/jupyterhub_config.py
@@ -1,16 +1,9 @@
 import os
-import sys
 from dockerspawner import DockerSpawner
-from jupyterhub.utils import random_port
 from nativeauthenticator import NativeAuthenticator
-import subprocess
-
-# from nbgrader.auth import JupyterHubAuthPlugin
-from traitlets import Unicode, Bool, Int, Float
 
 import secrets
 import string
-from datetime import datetime, timedelta
 from typing import Optional
 
 
@@ -40,21 +33,6 @@ def generate_api_token(
     return token
 
 
-def is_service_available_cmd(host, port):
-    """Check service using system commands"""
-    try:
-        subprocess.run(
-            ["nc", "-z", host, str(port)],
-            check=True,
-            timeout=3,
-            stdout=subprocess.DEVNULL,
-            stderr=subprocess.DEVNULL,
-        )
-        return True
-    except (subprocess.TimeoutExpired, subprocess.CalledProcessError):
-        return False
-
-
 # Configuration file for JupyterHub
 c = get_config()
 
@@ -139,60 +117,18 @@ c.Spawner.ip = "0.0.0.0"
 c.DockerSpawner.mem_limit = os.environ.get("NOTEBOOK_MEMORY_LIMIT", "500M")
 c.DockerSpawner.cpu_limit = float(os.environ.get("NOTEBOOK_CPU_LIMIT", "1.0"))
 
-
-"""
-# Services configuration for NBGrader
-c.JupyterHub.services = [
-    {
-        'name': 'nbgrader-formgrader',
-        'url': 'http://127.0.0.1:9999',
-        'command': [
-            'jupyter-nbgrader',
-            '--port=9999',
-            '--no-browser',
-            '--log-level=INFO'
-        ],
-        'cwd': '/srv/jupyterhub/courses',
-        'user': 'root',
-        'environment': {
-            'PYTHONPATH': '/srv/nbgrader',
-            'NBGRADER_CONFIG_FILE': '/srv/jupyterhub/nbgrader/nbgrader_config.py'
-        }
-    }
+# Fixing CORS because Nginx
+# this isn't a security risk because the container is served behind nginx
+# this only affects the traffic within the docker network itself
+c.Spawner.args = [
+    "--ServerApp.allow_origin=*",
+    "--ServerApp.allow_credentials=True",
+    "--ServerApp.disable_check_xsrf=True",
+    "--NotebookApp.allow_origin=*",
+    "--NotebookApp.allow_credentials=True",
+    "--NotebookApp.disable_check_xsrf=True",
+    '--ServerApp.tornado_settings={"headers": {"Access-Control-Allow-Origin": "*"}}',
 ]
-"""
-"""
-# NBGrader configuration
-c.JupyterHub.load_groups = {
-    'nbgrader-instructors': ['instructor'],
-    'nbgrader-students': []
-}
-"""
-"""
-# NBGrader Config 
-c.JupyterHub.services = [
-    {
-        'name': 'nbgrader-formgrader',
-        'url': 'http://127.0.0.1:9999',
-        'api_token': generate_api_token(prefix='nbgrader'),
-        'command': [
-            'python', '-m', 'nbgrader', 'formgrader',
-            #'--port=9999',
-            #'--no-browser',
-            '--log-level=INFO',
-            #'--base_url=/jupyter/services/nbgrader-formgrader',
-            '--debug'
-        ],
-        'environment': {
-            'JUPYTERHUB_SERVICE_URL': 'http://127.0.0.1:8081/jupyter/hub/api',
-            'NBGRADER_CONFIG_FILE': '/srv/nbgrader/nbgrader_config.py',
-            'PYTHONPATH': '/srv/nbgrader'
-        },
-        'cwd': '/srv/nbgrader/courses',
-        'user': 'root'
-    }
-]
-"""
 
 # Security settings
 c.JupyterHub.cookie_secret_file = "/srv/jupyterhub/cookie_secret"