k8s volumesnapshot已创建，但在python k8s客户端中返回409错误消息

Question

我使用python k8s客户端成功地快照了我的卷

然而，我得到了下面的信息

我在集群中没有相同的卷快照

为什么会这样

代码：

def create_快照（名称空间，pvc_名称）：

snapshot_class = "snapshotclass"
snapshot_name = f"snapshot-{pvc_name}"

snapshot_resource = {
"apiVersion": "snapshot.storage.k8s.io/v1beta1",
"kind": "VolumeSnapshot",
"metadata": {"name": snapshot_name},
"spec": {
    "volumeSnapshotClassName": snapshot_class,
    "source": {"persistentVolumeClaimName": pvc_name}
    }
}

res = custom_api.create_namespaced_custom_object(
    group="snapshot.storage.k8s.io",
    version="v1beta1",
    namespace= namespace,
    plural="volumesnapshots",
    body=snapshot_resource,
)

print(res)

create_snapshot("test", "test-pvc")

volumesnapshot已成功创建，但我收到一条消息：

  File "/home/new/my/test/rescheduler/utils/k8s_controller.py", line 72, in create_snapshot
    body=snapshot_resource,
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/api/custom_objects_api.py", line 225, in create_namespaced_custom_object
    return self.create_namespaced_custom_object_with_http_info(group, version, namespace, plural, body, **kwargs)  # noqa: E501
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/api/custom_objects_api.py", line 358, in create_namespaced_custom_object_with_http_info
    collection_formats=collection_formats)
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/api_client.py", line 353, in call_api
    _preload_content, _request_timeout, _host)
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/api_client.py", line 184, in __call_api
    _request_timeout=_request_timeout)
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/api_client.py", line 397, in request
    body=body)
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/rest.py", line 280, in POST
    body=body)
  File "/home/new/my/test/venv/lib/python3.6/site-packages/kubernetes/client/rest.py", line 233, in request
    raise ApiException(http_resp=r)
kubernetes.client.exceptions.ApiException: (409)
Reason: Conflict
HTTP response headers: HTTPHeaderDict({'Audit-Id': 'dec3c73a-e5fc-4c63-8d1a-6e2e6c6600e1', 'Cache-Control': 'no-cache, private', 'Content-Type': 'application/json', 'Date': 'my, 25 Apr 2021 10:50:52 GMT', 'Content-Length': '346'})
HTTP response body: {"kind":"Status","apiVersion":"v1","metadata":{},"status":"Failure","message":"volumesnapshots.snapshot.storage.k8s.io \"snapshot-test-pvc\" already exists","reason":"AlreadyExists","details":{"name":"snapshot-test-pvc,"group":"snapshot.storage.k8s.io","kind":"volumesnapshots"},"code":409}

Answer 1

将此答案发布为社区wiki，以给出在尝试使用上述代码片段创建资源时遇到错误409的可能原因之一

请随意扩展它

---

问题中遇到的错误：

Reason: Conflict
HTTP response headers: HTTPHeaderDict({'Audit-Id': 'dec3c73a-e5fc-4c63-8d1a-6e2e6c6600e1', 'Cache-Control': 'no-cache, private', 'Content-Type': 'application/json', 'Date': 'my, 25 Apr 2021 10:50:52 GMT', 'Content-Length': '346'})
HTTP response body: {"kind":"Status","apiVersion":"v1","metadata":{},"status":"Failure","message":"volumesnapshots.snapshot.storage.k8s.io \"snapshot-test-pvc\" already exists","reason":"AlreadyExists","details":{"name":"snapshot-test-pvc,"group":"snapshot.storage.k8s.io","kind":"volumesnapshots"},"code":409}

"snapshot-test-pvc\" already exists","reason":"AlreadyExists"

表示该资源已存在于群集中。要检查群集中是否存在资源，可以运行以下命令：

• $ kubectl get volumesnapshots -A
• $ kubectl describe volumesnapshots RESOURCE_NAME -A

我使用了问题中的代码，没有任何问题。行动方针如下：

• 第一次运行-VolumeSnapshot已成功创建
• 第二次运行-代码返回409错误，说明资源已存在

kubernetes.client.exceptions.ApiException: (409)
Reason: Conflict
<  REDACTED  > 
HTTP response body: {"kind":"Status","apiVersion":"v1","metadata":{},"status":"Failure","message":"volumesnapshots.snapshot.storage.k8s.io \"snapshot-example-pvc\" already exists","reason":"AlreadyExists","details":{"name":"snapshot-example-pvc","group":"snapshot.storage.k8s.io","kind":"volumesnapshots"},"code":409}

A side note!

Above error was returned with modified code from the question (mainly values).

在尝试对已创建的资源运行$ kubectl create -f resource.yaml -v=4时，也可以看到此错误

---

对于任何感兴趣的人来说，这里是问题中使用的代码的minimal, reproducible example（它丢失了import，并且def放错了位置）：

from kubernetes import client, config

def create_snapshot(namespace, pvc_name):

    config.load_kube_config()

    custom_api = client.CustomObjectsApi()

    snapshot_class = "snapshotclass"
    snapshot_name = f"snapshot-{pvc_name}"

    snapshot_resource = {
    "apiVersion": "snapshot.storage.k8s.io/v1beta1",
    "kind": "VolumeSnapshot",
    "metadata": {"name": snapshot_name},
    "spec": {
        "volumeSnapshotClassName": snapshot_class,
        "source": {"persistentVolumeClaimName": pvc_name}
        }
    }

    res = custom_api.create_namespaced_custom_object(
        group="snapshot.storage.k8s.io",
        version="v1beta1",
        namespace= namespace,
        plural="volumesnapshots",
        body=snapshot_resource,
    )

    print(res)

create_snapshot("default", "test-pvc")

---

额外资源：

• Github.com: Fabric8io: Kubernetes client: Issues: 409 conflict status code when create pod
• Oreilly.com: Library: View: Managing Kubernetes: Chapter 04