feat: generalize proxy assets for use with every storage

We do this so that custom storage does not need to be defined for Scorm
The default storage configured for Open edX should work out of the box with scorm now
This also fixes an issue of X-Frame-Options on the LMS when running in development mode
closes overhangio#87

openedxscorm/scormxblock.py

@@ -267,12 +267,11 @@ def assets_proxy(self, request, suffix):
         Response object containing the content of the requested file with the appropriate content type.
         """
         file_name = os.path.basename(suffix)
-        signed_url = self.storage.url(suffix)
-        if request.query_string:
-            signed_url = "&".join([signed_url, request.query_string])
+        file_path = self.find_file_path(file_name)        
         file_type, _ = mimetypes.guess_type(file_name)
-        with urllib.request.urlopen(signed_url) as response:
-            file_content = response.read()
+        with self.storage.open(file_path) as response:
+            file_content = response.read()        
+
 
         return Response(file_content, content_type=file_type)
 
@@ -420,16 +419,20 @@ def extract_package(self, package_file):
     def index_page_url(self):
         if not self.package_meta or not self.index_page_path:
             return ""
-        folder = self.extract_folder_path
         if self.storage.exists(
             os.path.join(self.extract_folder_base_path, self.clean_path(self.index_page_path))
         ):
             # For backward-compatibility, we must handle the case when the xblock data
             # is stored in the base folder.
-            folder = self.extract_folder_base_path
-            logger.warning("Serving SCORM content from old-style path: %s", folder)
+            logger.warning("Serving SCORM content from old-style path: %s", self.extract_folder_base_path)
+
+        return f"{self.proxy_base_url}/{self.index_page_path}"
 
-        return self.storage.url(os.path.join(folder, self.index_page_path))
+    @property
+    def proxy_base_url(self):
+        return self.runtime.handler_url(
+                self, "assets_proxy"
+            ).rstrip("?/")
 
     @property
     def extract_folder_path(self):
@@ -692,11 +695,7 @@ def find_titles_recursively(self, item, prefix, root):
                 f"{prefix}resources/{prefix}resource[@identifier='{item_identifier}']"
             )
             # Attach the storage path with the file path
-            resource_link = urllib.parse.unquote(
-                self.storage.url(
-                    os.path.join(self.extract_folder_path, resource.get("href"))
-                )
-            )
+            resource_link = f"{self.proxy_base_url}/{resource.get('href')}"
         if not children:
             return [(sanitized_title, resource_link)]
         child_titles = []
@@ -768,7 +767,7 @@ def find_file_path(self, filename):
         Search recursively in the extracted folder for a given file. Path of the first
         found file will be returned. Raise a ScormError if file cannot be found.
         """
-        path = self.get_file_path(filename, self.extract_folder_path)
+        path = self.get_file_path(filename, self.extract_folder_path) or self.get_file_path(filename, self.extract_folder_base_path)
         if path is None:
             raise ScormError(f"Invalid package: could not find '{filename}' file")
         return path

openedxscorm/storage.py

@@ -25,31 +25,6 @@ def __init__(
             querystring_expire=querystring_expire,
         )
 
-    def url(self, name, parameters=None, expire=None):
-        """
-        Override url method of S3Boto3Storage
-        """
-        if not self.querystring_auth:
-            # No need to use assets proxy when authentication is disabled
-            return super().url(name, parameters=parameters, expire=expire)
-
-        if name.startswith(self.xblock.extract_folder_path):
-            # Proxy assets serving through the `assets_proxy` view. This case should
-            # only ever happen when we attempt to serve the index page from the
-            # index_page_url method.
-            proxy_base_url = self.xblock.runtime.handler_url(
-                self.xblock, "assets_proxy"
-            ).rstrip("?/")
-            # Note that we serve the index page here.
-            return f"{proxy_base_url}/{self.xblock.index_page_path}"
-
-        # This branch is executed when the `url` method is called from `assets_proxy`
-        return super().url(
-            os.path.join(self.xblock.extract_folder_path, name),
-            parameters=parameters,
-            expire=expire,
-        )
-
 
 def s3(xblock):
     """