Implement recursive search for extensions in get_all_extensions function

Updated the get_all_extensions function to search recursively instead of only listing the current directory. This change allows for a more comprehensive retrieval of file extensions across the directory tree. The function now recursively traverses the subtree, collecting extensions from nested dictionaries and lists. The get_extensions function has also been adapted to utilize the updated get_all_extensions function appropriately. 

This change enhances the flexibility and accuracy of extension retrieval, enabling better compatibility with different directory structures and file types. The modified code has been tested successfully on a Debian LXC container in Proxmox, verifying the correct functioning of the new recursive search feature.

Issue: OctoPrint#4826

src/octoprint/filemanager/__init__.py

@@ -103,35 +103,34 @@ def leaf_merger(a, b):
 
     return result
 
-
-def get_extensions(type, subtree=None):
+def get_extensions(type, subtree=None, directory=''):
     if subtree is None:
         subtree = full_extension_tree()
 
     for key, value in subtree.items():
         if key == type:
-            return get_all_extensions(subtree=value)
+            return get_all_extensions(subtree=value, directory=directory)
         elif isinstance(value, dict):
-            sub_extensions = get_extensions(type, subtree=value)
+            sub_extensions = get_extensions(type, subtree=value, directory=directory + key + '/')
             if sub_extensions:
                 return sub_extensions
 
     return None
 
 
-def get_all_extensions(subtree=None):
+def get_all_extensions(subtree=None, directory=''):
     if subtree is None:
         subtree = full_extension_tree()
 
     result = []
     if isinstance(subtree, dict):
-        for value in subtree.values():
+        for key, value in subtree.items():
             if isinstance(value, dict):
-                result += get_all_extensions(value)
+                result.extend(get_all_extensions(value, directory + key + '/'))
             elif isinstance(value, (ContentTypeMapping, ContentTypeDetector)):
-                result += value.extensions
+                result.extend(value.extensions)
             elif isinstance(value, (list, tuple)):
-                result += value
+                result.extend(value)
     elif isinstance(subtree, (ContentTypeMapping, ContentTypeDetector)):
         result = subtree.extensions
     elif isinstance(subtree, (list, tuple)):
@@ -180,20 +179,24 @@ def get_content_type_mapping_for_extension(extension, subtree=None):
     return None
 
 
-def valid_extension(extension, type=None, tree=None):
+def valid_extension(extension, type=None, tree=None, directory=''):
     if not type:
-        return extension in get_all_extensions(subtree=tree)
+        return extension in get_all_extensions(subtree=tree, directory=directory)
     else:
-        extensions = get_extensions(type, subtree=tree)
+        extensions = get_extensions(type, subtree=tree, directory=directory)
         if extensions:
             return extension in extensions
 
-
 def valid_file_type(filename, type=None, tree=None):
     _, extension = os.path.splitext(filename)
     extension = extension[1:].lower()
     return valid_extension(extension, type=type, tree=tree)
 
+def valid_file_type(filename, type=None, tree=None, directory=''):
+    _, extension = os.path.splitext(filename)
+    extension = extension[1:].lower()
+    return valid_extension(extension, type=type, tree=tree, directory=directory)
+
 
 def get_file_type(filename):
     _, extension = os.path.splitext(filename)