docs: Add failed task snippet

examples/queues/failed.py

@@ -0,0 +1,19 @@
+# [START import]
+from typing import List
+from nitric.api import Queues, Task
+from nitric.api.queues import FailedTask
+# [END import]
+async def queues_failed():
+# [START snippet]
+    # Construct a new queue client with default settings 
+    queues = Queues()
+
+    payload = {"content": "of task"}
+
+    # Publish tasks to queue
+    failed_task = await queues.queue("my-queue").send([Task(payload=payload) for i in range(2)])
+
+    # Process the failed task
+    for task in failed_task:
+      print(task.message)
+# [END snippet]

tests/examples/test_queues_example.py

@@ -1,3 +1,8 @@
+from typing import List
+
+from nitricapi.nitric.queue.v1 import NitricTask, QueueSendBatchResponse, QueueSendResponse, FailedTask
+
+from examples.queues.failed import queues_failed
 from examples.queues.receive import queues_receive
 from examples.queues.send import queues_send
 
@@ -21,3 +26,21 @@ async def test_send_queue(self):
             await queues_send()
 
         mock_send.assert_called_once()
+
+    async def test_failed_queue(self):
+        mock_failed = AsyncMock()
+        mock_failed.return_value = QueueSendBatchResponse(
+            failed_tasks=[
+                FailedTask(
+                    task=NitricTask(
+                        id="1",
+                    ),
+                    message="failed to send in this test",
+                )
+            ]
+        )
+
+        with patch("nitricapi.nitric.queue.v1.QueueServiceStub.send_batch", mock_failed):
+            await queues_failed()
+
+        mock_failed.assert_called_once()