Initial commit

venv/Lib/site-packages/django/utils/asyncio.py

@@ -0,0 +1,39 @@
+import asyncio
+import functools
+import os
+
+from django.core.exceptions import SynchronousOnlyOperation
+
+
+def async_unsafe(message):
+    """
+    Decorator to mark functions as async-unsafe. Someone trying to access
+    the function while in an async context will get an error message.
+    """
+
+    def decorator(func):
+        @functools.wraps(func)
+        def inner(*args, **kwargs):
+            if not os.environ.get("DJANGO_ALLOW_ASYNC_UNSAFE"):
+                # Detect a running event loop in this thread.
+                try:
+                    asyncio.get_running_loop()
+                except RuntimeError:
+                    pass
+                else:
+                    raise SynchronousOnlyOperation(message)
+            # Pass onward.
+            return func(*args, **kwargs)
+
+        return inner
+
+    # If the message is actually a function, then be a no-arguments decorator.
+    if callable(message):
+        func = message
+        message = (
+            "You cannot call this from an async context - use a thread or "
+            "sync_to_async."
+        )
+        return decorator(func)
+    else:
+        return decorator