chore: import upstream snapshot with attribution

doc/source/serve/doc_code/http_guide/disconnects.py

@@ -0,0 +1,121 @@
+# flake8: noqa
+# fmt: off
+
+import ray
+import sys
+from typing import List
+
+from ray._common.test_utils import wait_for_condition
+
+
+# Overwrite print statement to make doc code testable
+@ray.remote
+class PrintStorage:
+    def __init__(self):
+        self.print_storage: List[str] = []
+
+    def add(self, s: str):
+        self.print_storage.append(s)
+
+    def clear(self):
+        self.print_storage.clear()
+
+    def get(self) -> List[str]:
+        return self.print_storage
+
+
+print_storage_handle = PrintStorage.remote()
+
+
+def print(string: str):
+    ray.get(print_storage_handle.add.remote(string))
+    sys.stdout.write(f"{string}\n")
+
+
+# __start_basic_disconnect__
+import asyncio
+from ray import serve
+
+
+@serve.deployment
+async def startled():
+    try:
+        print("Replica received request!")
+        await asyncio.sleep(10000)
+    except asyncio.CancelledError:
+        # Add custom behavior that should run
+        # upon cancellation here.
+        print("Request got cancelled!")
+# __end_basic_disconnect__
+
+serve.run(startled.bind())
+
+import requests
+from requests.exceptions import Timeout
+
+# Intentionally time out request to test cancellation behavior
+try:
+    requests.get("http://localhost:8000", timeout=0.5)
+except Timeout:
+    pass
+
+wait_for_condition(
+    lambda: {"Replica received request!", "Request got cancelled!"}
+    == set(ray.get(print_storage_handle.get.remote())),
+    timeout=5,
+)
+
+sys.stdout.write(f"{ray.get(print_storage_handle.get.remote())}\n")
+
+ray.get(print_storage_handle.clear.remote())
+
+
+# __start_shielded_disconnect__
+import asyncio
+from ray import serve
+
+
+@serve.deployment
+class SnoringSleeper:
+    async def snore(self):
+        await asyncio.sleep(1)
+        print("ZZZ")
+
+    async def __call__(self):
+        try:
+            print("SnoringSleeper received request!")
+
+            # Prevent the snore() method from being cancelled
+            await asyncio.shield(self.snore())
+
+        except asyncio.CancelledError:
+            print("SnoringSleeper's request was cancelled!")
+
+
+app = SnoringSleeper.bind()
+# __end_shielded_disconnect__
+
+serve.run(app)
+
+import requests
+from requests.exceptions import Timeout
+
+# Intentionally time out request to test cancellation behavior
+try:
+    requests.get("http://localhost:8000", timeout=0.5)
+except Timeout:
+    pass
+
+wait_for_condition(
+    lambda: {
+        "SnoringSleeper received request!",
+        "SnoringSleeper's request was cancelled!",
+        "ZZZ",
+    }
+    == set(ray.get(print_storage_handle.get.remote())),
+    timeout=5,
+)
+
+sys.stdout.write(f"{ray.get(print_storage_handle.get.remote())}\n")
+
+ray.get(print_storage_handle.clear.remote())