Initial import: Music_Server, MusicFree, catalog-sync

catalog-sync/musicdl/modules/utils/importutils.py

@@ -0,0 +1,38 @@
+'''
+Function:
+    Implementation of Optional Import Related Utils
+Author:
+    Zhenchao Jin
+WeChat Official Account (微信公众号):
+    Charles的皮卡丘
+'''
+import sys
+import warnings
+import importlib
+
+
+'''optionalimport'''
+def optionalimport(name: str, show_warning: bool = False):
+    if name in sys.modules: return sys.modules[name]
+    try:
+        return importlib.import_module(name)
+    except ModuleNotFoundError:
+        missing = getattr(optionalimport, "_missing", set())
+        if (name not in missing) and show_warning: warnings.warn(f'Optional dependency "{name}" is not installed; skipping import.', category=ImportWarning, stacklevel=2)
+        missing.add(name)
+        optionalimport._missing = missing
+        return None
+
+
+'''optionalimportfrom'''
+def optionalimportfrom(module: str, attr: str, show_warning: bool = False):
+    try:
+        mod = sys.modules.get(module) or importlib.import_module(module)
+        return (getattr(mod, attr) if hasattr(mod, attr) else importlib.import_module(f"{module}.{attr}"))
+    except (ModuleNotFoundError, AttributeError):
+        key = (module, attr)
+        missing = getattr(optionalimportfrom, "_missing", set())
+        if (key not in missing) and show_warning: warnings.warn(f"Optional import failed: from {module} import {attr}", ImportWarning, stacklevel=2)
+        missing.add(key)
+        optionalimportfrom._missing = missing
+        return None