kubernetes-client / python

Official Python client library for kubernetes
http://kubernetes.io/
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The dynamic client example, `kubernetes.client.ApiClient(...)` takes in the result of `kubernetes.config.load_kube_config(...)`, which is empty #2279

Open tonur opened 2 months ago

tonur commented 2 months ago

Link to the issue (please include a link to the specific documentation or example): Example where client.ApiClient(configuration=config.load_kube_config()) is used: https://github.com/kubernetes-client/python/blob/master/examples/dynamic-client/configmap.py#L27 Link to where config function load_kube_config() does not return anything: https://github.com/kubernetes-client/python/blob/master/kubernetes/base/config/kube_config.py#L799

Description of the issue (please include outputs or screenshots if possible): I would assume that when configuring an ApiClient, I should send the argument of the configuration object. However, since the config.load_kube_config() does not return anything, I feel that this example is wrong.

I would assume I should do the following:

from kubernetes import config, dynamic
from kubernetes.client import api_client
configuration = client.Configuration()
config.load_kube_config()
client = api_client.ApiClient(configuration=configuration)

Since the config.load_kube_config() has this in the description: "Loads authentication and cluster information from kube-config file and stores them in kubernetes.client.configuration." So that the client.Configuration() returned value is updated after being instantiated and thus can be passed to the api_client.ApiClient(...) function.

Can anyone please correct me if I am wrong? I am unsure of what the correct way to get an ApiClient. Thanks in advance!

yliaog commented 2 months ago

@fabianvf could you help take a look?

fabianvf commented 2 months ago

@tonur you're correct, the client is being instatiated there oddly. To create the dynamic client, you instantiate an API client and pass it in, so the proper series of calls would be:

from kubernetes import config, dynamic
from kubernetes.client import api_client

configuration = client.Configuration()
config.load_kube_config()

api_client = api_client.ApiClient(configuration=configuration)
dynamic_client = dynamic.DynamicClient(api_client)
tonur commented 2 months ago

Is it okay that I make a Pull Request to change this in the example? Or is it something you'd rather do?

fabianvf commented 2 months ago

@tonur absolutely! A PR would be appreciated

tonur commented 2 months ago

@tonur you're correct, the client is being instatiated there oddly. To create the dynamic client, you instantiate an API client and pass it in, so the proper series of calls would be:

from kubernetes import config, dynamic
from kubernetes.client import api_client

configuration = client.Configuration()
config.load_kube_config()

api_client = api_client.ApiClient(configuration=configuration)
dynamic_client = dynamic.DynamicClient(api_client)

Hey there @fabianvf. I found that this is not working for me at the moment... I have no idea what is going on, but somehow this is not working:

from kubernetes import client
from kubernetes import config as k8sconfig

cluster_namespace = "test-cluster-namespace"
cluster_name = "test-cluster-name"
kubeconfig_file = "/tmp/k8s_config"

configuration = client.Configuration()
k8sconfig.load_kube_config(config_file=kubeconfig_file, context=f"{cluster_name}-admin@{cluster_name}")
cluster_client = client.ApiClient(configuration)

This ends up trying to connect to "localhost:80" instead of the correct IP and Port for the Kubernetes cluster, outlined in the kubeconfig_file.

But this is somehow working:

from kubernetes import client
from kubernetes import config as k8sconfig

cluster_namespace = "test-cluster-namespace"
cluster_name = "test-cluster-name"
kubeconfig_file = "/tmp/k8s_config"

cluster_client = client.ApiClient(configuration=k8sconfig.load_kube_config(config_file=kubeconfig_file, context=f"{cluster_name}-admin@{cluster_name}"))

I don't know what strange magic that the config.load_kube_config() function is returning, I am at a loss for words.

I would propose to document this in the example to discourage future optimists (like me) from spending hours trying to make a more "clean" and "clear" syntax work... 🤦