1  import falcon
 2  import os
 3  import mimetypes
 4  
 5  class StaticResource:
 6      def __init__(self, static_dir):
 7          """
 8          Initialize the StaticResource with a specific static directory.
 9          """
10          self.static_dir = os.path.abspath(static_dir)
11  
12      def on_get(self, req, resp, filepath=""):
13          """
14          Handles requests for both root files and nested assets.
15          """
16          # Ensure filepath is safely joined to prevent path traversal
17          file_path = os.path.normpath(os.path.join(self.static_dir, filepath))
18  
19          # Prevent path traversal by ensuring the file_path starts with static_dir
20          if not file_path.startswith(self.static_dir):
21              resp.status = falcon.HTTP_404
22              resp.text = "404 - Not Found"
23              return
24  
25          # Handle fallback for missing assets
26          if not os.path.isfile(file_path):
27              if filepath == "favicon.ico":
28                  resp.status = falcon.HTTP_404
29                  resp.text = "404 - Favicon not found"
30                  return
31              file_path = os.path.join(self.static_dir, "index.html")
32  
33          # Determine MIME type
34          mime_type, _ = mimetypes.guess_type(file_path)
35          resp.content_type = mime_type or "application/octet-stream"
36  
37          # Serve the file
38          try:
39              with open(file_path, "rb") as f:
40                  resp.data = f.read()
41          except Exception as e:
42              resp.status = falcon.HTTP_500
43              resp.text = f"Error serving file: {str(e)}"