Load kubect config file using Kubernetes Python client returns error: Invalid kube-config file-CodePudding

I wrote a service to retrieve some information from the Kubernetes cluster. Below is a snippet from the kubernetes_service.py file that works perfectly when I run it on my local machine.

from kubernetes.client.rest import ApiException
from kubernetes import client, config
from exceptions.logs_not_found_exceptions import LogsNotFound
import logging

log = logging.getLogger("services/kubernetes_service.py")


class KubernetesService:
    def __init__(self):
        super().__init__()
        config.load_kube_config()
        self.api_instance = client.CoreV1Api()

    def get_pods(self, body):
        try:
            api_response = self.api_instance.list_namespaced_pod(namespace=body['namespace'])
            dict_response = api_response.to_dict()
            pods = []
            for item in dict_response['items']:
                pods.append(item['metadata']['name'])

            log.info(f"Retrieved the pods: {pods}")
            return pods
        except ApiException as e:
            raise ApiException(e)

    def get_logs(self, body):
        try:
            api_response = self.api_instance.read_namespaced_pod_log(name=body['pod_name'], namespace=body['namespace'])
            tail_logs = api_response[len(api_response)-16000:]

            log.info(f"Retrieved the logs: {tail_logs}")
            return tail_logs
        except ApiException:
            raise LogsNotFound(body['namespace'], body['pod_name'])

When creating the docker image using Dockerfile, it also installed kubectl. Below is my Dockerfile.

FROM python:3.8-alpine
RUN mkdir /app
WORKDIR /app

COPY requirements.txt .
RUN pip install -r requirements.txt && rm requirements.txt

RUN apk add curl openssl bash --no-cache
RUN curl -LO "https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl" \
    && chmod  x ./kubectl \
    && mv ./kubectl /usr/local/bin/kubectl

COPY . .
EXPOSE 8087
ENTRYPOINT [ "python", "bot.py"]

To grant the container permissions to run the command kubectl get pods I added the role in the deployment.yml file:

apiVersion: v1
kind: Service
metadata:
  name: pyhelper
spec:
  selector:
    app: pyhelper
  ports:
    - protocol: "TCP"
      port: 8087
      targetPort: 8087
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: pyhelper
spec:
  selector:
    matchLabels:
      app: pyhelper
  replicas: 1
  template:
    metadata:
      labels:
        app: pyhelper
    spec:
      serviceAccountName: k8s-101-role
      containers:
        - name: pyhelper
          image: **********
          imagePullPolicy: Always
          ports:
            - containerPort: 8087
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: k8s-101-role
subjects:
  - kind: ServiceAccount
    name: k8s-101-role
    namespace: ind-iv
roleRef:
  kind: ClusterRole
  name: cluster-admin
  apiGroup: rbac.authorization.k8s.io
---
apiVersion: v1
kind: ServiceAccount
metadata:
  name: k8s-101-role

At the start up of the container it returns the error kubernetes.config.config_exception.ConfigException: Invalid kube-config file. No configuration found at the line config.load_kube_config() in the kubernetes_service.py file. I checked the config file by running the command kubectl config view and the file is indeed empty. What am I doing wrong here? Empty config file:

apiVersion: v1
clusters: null
contexts: null
current-context: ""
kind: Config
preferences: {}
users: null

Also tried to run the command kubectl get pods in the shell of the container and it successfully returned the pods.

CodePudding user response：

I believe you'll want kubernetes.config.load_config which differs from the load_kube_config you're currently using in that the package-level one looks for any $HOME/.kube/config as you expected, but then falls back to the in-cluster config as the ServiceAccount usage expects

from kubernetes.config import load_config

class KubernetesService:
    def __init__(self):
        super().__init__()
        load_config()