[ie/youtube] Add a PO Token Provider Framework (#12840)

https://github.com/yt-dlp/yt-dlp/tree/master/yt_dlp/extractor/youtube/pot/README.md

Authored by: coletdjnz

test/test_pot/conftest.py

@@ -0,0 +1,71 @@
+import collections
+
+import pytest
+
+from yt_dlp import YoutubeDL
+from yt_dlp.cookies import YoutubeDLCookieJar
+from yt_dlp.extractor.common import InfoExtractor
+from yt_dlp.extractor.youtube.pot._provider import IEContentProviderLogger
+from yt_dlp.extractor.youtube.pot.provider import PoTokenRequest, PoTokenContext
+from yt_dlp.utils.networking import HTTPHeaderDict
+
+
+class MockLogger(IEContentProviderLogger):
+
+    log_level = IEContentProviderLogger.LogLevel.TRACE
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.messages = collections.defaultdict(list)
+
+    def trace(self, message: str):
+        self.messages['trace'].append(message)
+
+    def debug(self, message: str):
+        self.messages['debug'].append(message)
+
+    def info(self, message: str):
+        self.messages['info'].append(message)
+
+    def warning(self, message: str, *, once=False):
+        self.messages['warning'].append(message)
+
+    def error(self, message: str):
+        self.messages['error'].append(message)
+
+
+@pytest.fixture
+def ie() -> InfoExtractor:
+    ydl = YoutubeDL()
+    return ydl.get_info_extractor('Youtube')
+
+
+@pytest.fixture
+def logger() -> MockLogger:
+    return MockLogger()
+
+
+@pytest.fixture()
+def pot_request() -> PoTokenRequest:
+    return PoTokenRequest(
+        context=PoTokenContext.GVS,
+        innertube_context={'client': {'clientName': 'WEB'}},
+        innertube_host='youtube.com',
+        session_index=None,
+        player_url=None,
+        is_authenticated=False,
+        video_webpage=None,
+
+        visitor_data='example-visitor-data',
+        data_sync_id='example-data-sync-id',
+        video_id='example-video-id',
+
+        request_cookiejar=YoutubeDLCookieJar(),
+        request_proxy=None,
+        request_headers=HTTPHeaderDict(),
+        request_timeout=None,
+        request_source_address=None,
+        request_verify_tls=True,
+
+        bypass_cache=False,
+    )