examples: update url extraction rule

examples/example.py

@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+
 import os
 import sys
 import webbrowser

examples/flask_server.py

@@ -1,3 +1,5 @@
+#!/usr/bin/env python3
+
 import os
 import re
 import sys
@@ -14,6 +16,7 @@ examples_dir = os.path.dirname(os.path.abspath(__file__))
 sys.path.append(os.path.dirname(examples_dir))
 from cloudflare_error_page import get_resources_folder, render as render_cf_error_page
 
+# TODO: use blueprint
 app = Flask(__name__)
 
 # You can use resources from Cloudflare CDN. But in case of changing, you can set use_cdn = False to use bundled resources.
@@ -24,7 +27,7 @@ if use_cdn:
 
     # This handler is used to provide stylesheet and icon resources for the error page. If you pass use_cdn=True to render_cf_error_page
     # or if your site is under proxy of Cloudflare (the cdn-cgi folder is already provided by Cloudflare), this handler can be removed.
-    @app.route("/cdn-cgi/<path:path>")
+    @app.route('/cdn-cgi/<path:path>')
     def cdn_cgi(path):
         return send_from_directory(res_folder, path)
 
@@ -32,7 +35,7 @@ if use_cdn:
 param_cache: dict[str, dict] = {}
 
 def get_page_params(name: str) -> dict:
-    name = re.sub(r'[/\\]', '', name)
+    name = re.sub(r'[^\w]', '', name)
     params = param_cache.get(name)
     if params is not None:
         return params
@@ -45,9 +48,11 @@ def get_page_params(name: str) -> dict:
         return None
 
 
-@app.route("/", defaults={'name': 'default'})
-@app.route("/<name>")
+@app.route('/', defaults={'name': 'default'})
+@app.route('/<path:name>')
 def index(name: str):
+    name = os.path.basename(name)  # keep only the base name
+
     params = get_page_params(name)
     if params is None:
         abort(404)
@@ -62,13 +67,22 @@ def index(name: str):
 
     params = {
         **params,
-        "ray_id": ray_id,
-        "client_ip": client_ip,
+        'ray_id': ray_id,
+        'client_ip': client_ip,
     }
 
     # Render the error page
     return render_cf_error_page(params, use_cdn=use_cdn), 500
 
 
-if __name__ == "__main__":
-    app.run(debug=True)
+if __name__ == '__main__':
+    if len(sys.argv) > 1:
+        host = sys.argv[1]
+    else:
+        host = None
+    if len(sys.argv) > 2:
+        port = int(sys.argv[2])
+    else:
+        port = None
+    
+    app.run(debug=True, host=host, port=port)