[core] Load plugins on demand (#11305)

- Adds `--no-plugin-dirs` to disable plugin loading
- `--plugin-dirs` now supports post-processors

Authored by: coletdjnz, Grub4K, pukkandan

1 files changed, 176 insertions, 22 deletions

diff --git a/test/test_plugins.py b/test/test_plugins.py
index 77545d136..195726b18 100644
--- a/test/test_plugins.py
+++ b/test/test_plugins.py
@@ -10,22 +10,71 @@ TEST_DATA_DIR = Path(os.path.dirname(os.path.abspath(__file__)), 'testdata')
 sys.path.append(str(TEST_DATA_DIR))
 importlib.invalidate_caches()
 
-from yt_dlp.utils import Config
-from yt_dlp.plugins import PACKAGE_NAME, directories, load_plugins
+from yt_dlp.plugins import (
+    PACKAGE_NAME,
+    PluginSpec,
+    directories,
+    load_plugins,
+    load_all_plugins,
+    register_plugin_spec,
+)
+
+from yt_dlp.globals import (
+    extractors,
+    postprocessors,
+    plugin_dirs,
+    plugin_ies,
+    plugin_pps,
+    all_plugins_loaded,
+    plugin_specs,
+)
+
+
+EXTRACTOR_PLUGIN_SPEC = PluginSpec(
+    module_name='extractor',
+    suffix='IE',
+    destination=extractors,
+    plugin_destination=plugin_ies,
+)
+
+POSTPROCESSOR_PLUGIN_SPEC = PluginSpec(
+    module_name='postprocessor',
+    suffix='PP',
+    destination=postprocessors,
+    plugin_destination=plugin_pps,
+)
+
+
+def reset_plugins():
+    plugin_ies.value = {}
+    plugin_pps.value = {}
+    plugin_dirs.value = ['default']
+    plugin_specs.value = {}
+    all_plugins_loaded.value = False
+    # Clearing override plugins is probably difficult
+    for module_name in tuple(sys.modules):
+        for plugin_type in ('extractor', 'postprocessor'):
+            if module_name.startswith(f'{PACKAGE_NAME}.{plugin_type}.'):
+                del sys.modules[module_name]
+
+    importlib.invalidate_caches()
 
 
 class TestPlugins(unittest.TestCase):
 
     TEST_PLUGIN_DIR = TEST_DATA_DIR / PACKAGE_NAME
 
+    def setUp(self):
+        reset_plugins()
+
+    def tearDown(self):
+        reset_plugins()
+
     def test_directories_containing_plugins(self):
         self.assertIn(self.TEST_PLUGIN_DIR, map(Path, directories()))
 
     def test_extractor_classes(self):
-        for module_name in tuple(sys.modules):
-            if module_name.startswith(f'{PACKAGE_NAME}.extractor'):
-                del sys.modules[module_name]
-        plugins_ie = load_plugins('extractor', 'IE')
+        plugins_ie = load_plugins(EXTRACTOR_PLUGIN_SPEC)
 
         self.assertIn(f'{PACKAGE_NAME}.extractor.normal', sys.modules.keys())
         self.assertIn('NormalPluginIE', plugins_ie.keys())
@@ -35,17 +84,29 @@ class TestPlugins(unittest.TestCase):
             f'{PACKAGE_NAME}.extractor._ignore' in sys.modules,
             'loaded module beginning with underscore')
         self.assertNotIn('IgnorePluginIE', plugins_ie.keys())
+        self.assertNotIn('IgnorePluginIE', plugin_ies.value)
 
         # Don't load extractors with underscore prefix
         self.assertNotIn('_IgnoreUnderscorePluginIE', plugins_ie.keys())
+        self.assertNotIn('_IgnoreUnderscorePluginIE', plugin_ies.value)
 
         # Don't load extractors not specified in __all__ (if supplied)
         self.assertNotIn('IgnoreNotInAllPluginIE', plugins_ie.keys())
+        self.assertNotIn('IgnoreNotInAllPluginIE', plugin_ies.value)
         self.assertIn('InAllPluginIE', plugins_ie.keys())
+        self.assertIn('InAllPluginIE', plugin_ies.value)
+
+        # Don't load override extractors
+        self.assertNotIn('OverrideGenericIE', plugins_ie.keys())
+        self.assertNotIn('OverrideGenericIE', plugin_ies.value)
+        self.assertNotIn('_UnderscoreOverrideGenericIE', plugins_ie.keys())
+        self.assertNotIn('_UnderscoreOverrideGenericIE', plugin_ies.value)
 
     def test_postprocessor_classes(self):
-        plugins_pp = load_plugins('postprocessor', 'PP')
+        plugins_pp = load_plugins(POSTPROCESSOR_PLUGIN_SPEC)
         self.assertIn('NormalPluginPP', plugins_pp.keys())
+        self.assertIn(f'{PACKAGE_NAME}.postprocessor.normal', sys.modules.keys())
+        self.assertIn('NormalPluginPP', plugin_pps.value)
 
     def test_importing_zipped_module(self):
         zip_path = TEST_DATA_DIR / 'zipped_plugins.zip'
@@ -58,10 +119,10 @@ class TestPlugins(unittest.TestCase):
                 package = importlib.import_module(f'{PACKAGE_NAME}.{plugin_type}')
                 self.assertIn(zip_path / PACKAGE_NAME / plugin_type, map(Path, package.__path__))
 
-            plugins_ie = load_plugins('extractor', 'IE')
+            plugins_ie = load_plugins(EXTRACTOR_PLUGIN_SPEC)
             self.assertIn('ZippedPluginIE', plugins_ie.keys())
 
-            plugins_pp = load_plugins('postprocessor', 'PP')
+            plugins_pp = load_plugins(POSTPROCESSOR_PLUGIN_SPEC)
             self.assertIn('ZippedPluginPP', plugins_pp.keys())
 
         finally:
@@ -69,23 +130,116 @@ class TestPlugins(unittest.TestCase):
             os.remove(zip_path)
             importlib.invalidate_caches()  # reset the import caches
 
-    def test_plugin_dirs(self):
-        # Internal plugin dirs hack for CLI --plugin-dirs
-        # To be replaced with proper system later
-        custom_plugin_dir = TEST_DATA_DIR / 'plugin_packages'
-        Config._plugin_dirs = [str(custom_plugin_dir)]
-        importlib.invalidate_caches()  # reset the import caches
+    def test_reloading_plugins(self):
+        reload_plugins_path = TEST_DATA_DIR / 'reload_plugins'
+        load_plugins(EXTRACTOR_PLUGIN_SPEC)
+        load_plugins(POSTPROCESSOR_PLUGIN_SPEC)
 
+        # Remove default folder and add reload_plugin path
+        sys.path.remove(str(TEST_DATA_DIR))
+        sys.path.append(str(reload_plugins_path))
+        importlib.invalidate_caches()
         try:
-            package = importlib.import_module(f'{PACKAGE_NAME}.extractor')
-            self.assertIn(custom_plugin_dir / 'testpackage' / PACKAGE_NAME / 'extractor', map(Path, package.__path__))
-
-            plugins_ie = load_plugins('extractor', 'IE')
-            self.assertIn('PackagePluginIE', plugins_ie.keys())
+            for plugin_type in ('extractor', 'postprocessor'):
+                package = importlib.import_module(f'{PACKAGE_NAME}.{plugin_type}')
+                self.assertIn(reload_plugins_path / PACKAGE_NAME / plugin_type, map(Path, package.__path__))
+
+            plugins_ie = load_plugins(EXTRACTOR_PLUGIN_SPEC)
+            self.assertIn('NormalPluginIE', plugins_ie.keys())
+            self.assertTrue(
+                plugins_ie['NormalPluginIE'].REPLACED,
+                msg='Reloading has not replaced original extractor plugin')
+            self.assertTrue(
+                extractors.value['NormalPluginIE'].REPLACED,
+                msg='Reloading has not replaced original extractor plugin globally')
+
+            plugins_pp = load_plugins(POSTPROCESSOR_PLUGIN_SPEC)
+            self.assertIn('NormalPluginPP', plugins_pp.keys())
+            self.assertTrue(plugins_pp['NormalPluginPP'].REPLACED,
+                            msg='Reloading has not replaced original postprocessor plugin')
+            self.assertTrue(
+                postprocessors.value['NormalPluginPP'].REPLACED,
+                msg='Reloading has not replaced original postprocessor plugin globally')
 
         finally:
-            Config._plugin_dirs = []
-            importlib.invalidate_caches()  # reset the import caches
+            sys.path.remove(str(reload_plugins_path))
+            sys.path.append(str(TEST_DATA_DIR))
+            importlib.invalidate_caches()
+
+    def test_extractor_override_plugin(self):
+        load_plugins(EXTRACTOR_PLUGIN_SPEC)
+
+        from yt_dlp.extractor.generic import GenericIE
+
+        self.assertEqual(GenericIE.TEST_FIELD, 'override')
+        self.assertEqual(GenericIE.SECONDARY_TEST_FIELD, 'underscore-override')
+
+        self.assertEqual(GenericIE.IE_NAME, 'generic+override+underscore-override')
+        importlib.invalidate_caches()
+        #  test that loading a second time doesn't wrap a second time
+        load_plugins(EXTRACTOR_PLUGIN_SPEC)
+        from yt_dlp.extractor.generic import GenericIE
+        self.assertEqual(GenericIE.IE_NAME, 'generic+override+underscore-override')
+
+    def test_load_all_plugin_types(self):
+
+        # no plugin specs registered
+        load_all_plugins()
+
+        self.assertNotIn(f'{PACKAGE_NAME}.extractor.normal', sys.modules.keys())
+        self.assertNotIn(f'{PACKAGE_NAME}.postprocessor.normal', sys.modules.keys())
+
+        register_plugin_spec(EXTRACTOR_PLUGIN_SPEC)
+        register_plugin_spec(POSTPROCESSOR_PLUGIN_SPEC)
+        load_all_plugins()
+        self.assertTrue(all_plugins_loaded.value)
+
+        self.assertIn(f'{PACKAGE_NAME}.extractor.normal', sys.modules.keys())
+        self.assertIn(f'{PACKAGE_NAME}.postprocessor.normal', sys.modules.keys())
+
+    def test_no_plugin_dirs(self):
+        register_plugin_spec(EXTRACTOR_PLUGIN_SPEC)
+        register_plugin_spec(POSTPROCESSOR_PLUGIN_SPEC)
+
+        plugin_dirs.value = []
+        load_all_plugins()
+
+        self.assertNotIn(f'{PACKAGE_NAME}.extractor.normal', sys.modules.keys())
+        self.assertNotIn(f'{PACKAGE_NAME}.postprocessor.normal', sys.modules.keys())
+
+    def test_set_plugin_dirs(self):
+        custom_plugin_dir = str(TEST_DATA_DIR / 'plugin_packages')
+        plugin_dirs.value = [custom_plugin_dir]
+
+        load_plugins(EXTRACTOR_PLUGIN_SPEC)
+
+        self.assertIn(f'{PACKAGE_NAME}.extractor.package', sys.modules.keys())
+        self.assertIn('PackagePluginIE', plugin_ies.value)
+
+    def test_invalid_plugin_dir(self):
+        plugin_dirs.value = ['invalid_dir']
+        with self.assertRaises(ValueError):
+            load_plugins(EXTRACTOR_PLUGIN_SPEC)
+
+    def test_append_plugin_dirs(self):
+        custom_plugin_dir = str(TEST_DATA_DIR / 'plugin_packages')
+
+        self.assertEqual(plugin_dirs.value, ['default'])
+        plugin_dirs.value.append(custom_plugin_dir)
+        self.assertEqual(plugin_dirs.value, ['default', custom_plugin_dir])
+
+        load_plugins(EXTRACTOR_PLUGIN_SPEC)
+
+        self.assertIn(f'{PACKAGE_NAME}.extractor.package', sys.modules.keys())
+        self.assertIn('PackagePluginIE', plugin_ies.value)
+
+    def test_get_plugin_spec(self):
+        register_plugin_spec(EXTRACTOR_PLUGIN_SPEC)
+        register_plugin_spec(POSTPROCESSOR_PLUGIN_SPEC)
+
+        self.assertEqual(plugin_specs.value.get('extractor'), EXTRACTOR_PLUGIN_SPEC)
+        self.assertEqual(plugin_specs.value.get('postprocessor'), POSTPROCESSOR_PLUGIN_SPEC)
+        self.assertIsNone(plugin_specs.value.get('invalid'))
 
 
 if __name__ == '__main__':