[cleanup] Add more ruff rules (#10149)

[yt-dlp.git] / devscripts / lazy_load_template.py

diff --git a/devscripts/lazy_load_template.py b/devscripts/lazy_load_template.py
index b984aab9b1e34cee7895f3655502ffeff66e3c29..6f52165c5c551fe58d37d63696eb7c9660d588c2 100644 (file)
--- a/devscripts/lazy_load_template.py
+++ b/devscripts/lazy_load_template.py
@@ -1,17 +1,39 @@
-# encoding: utf-8
-from __future__ import unicode_literals
-
+import importlib
+import random
 import re
 
+from ..utils import (
+    age_restricted,
+    bug_reports_message,
+    classproperty,
+    variadic,
+    write_string,
+)
+
+# These bloat the lazy_extractors, so allow them to passthrough silently
+ALLOWED_CLASSMETHODS = {'extract_from_webpage', 'get_testcases', 'get_webpage_testcases'}
+_WARNED = False
+
+
+class LazyLoadMetaClass(type):
+    def __getattr__(cls, name):
+        global _WARNED
+        if ('_real_class' not in cls.__dict__
+                and name not in ALLOWED_CLASSMETHODS and not _WARNED):
+            _WARNED = True
+            write_string('WARNING: Falling back to normal extractor since lazy extractor '
+                         f'{cls.__name__} does not have attribute {name}{bug_reports_message()}\n')
+        return getattr(cls.real_class, name)
 
-class LazyLoadExtractor(object):
-    _module = None
 
-    @classmethod
-    def ie_key(cls):
-        return cls.__name__[:-2]
+class LazyLoadExtractor(metaclass=LazyLoadMetaClass):
+    @classproperty
+    def real_class(cls):
+        if '_real_class' not in cls.__dict__:
+            cls._real_class = getattr(importlib.import_module(cls._module), cls.__name__)
+        return cls._real_class
 
-    def __new__(cls):
-        mod = __import__(cls._module, fromlist=(cls.__name__,))
-        real_cls = getattr(mod, cls.__name__)
-        return real_cls.__new__(real_cls)
+    def __new__(cls, *args, **kwargs):
+        instance = cls.real_class.__new__(cls.real_class)
+        instance.__init__(*args, **kwargs)
+        return instance