gistfile1.py

@dxr_blueprint.route('/<path:tree_and_path>')
def browse(tree_and_path):
    """Show a directory listing or a single file from one of the trees."""
    tree, _, path = tree_and_path.partition('/')
    tree_folder = os.path.join(current_app.instance_path, 'trees', tree)

    if isdir(os.path.join(tree_folder, path)):
        # It's a bare directory. Add the index file to the end:
        path = os.path.join(path, current_app.config['DIRECTORY_INDEX'])
    else:
        # It's a file. Add the .html extension:
        path += '.html'

    return send_from_directory(tree_folder, path)