Create EKS kubeconfig using python and boto3

kubeconfig-generator.py

import boto3
import yaml

region = "eu-west-1"  # change the region if needed
cluster_name = "XXXXX"  # put your cluster name
config_output_file = "config.yml"  # change the path or file name if needed
is_local = True  # this script will be executed using ~/.aws/credentials file

# Initial boto3 session
session = boto3.Session(region_name=region)


# If you are using this script inside a k8s pod or other resource of AWS that has an attached role, use this method.
def client_assuming_role(ses):
    sts = ses.client("sts")
    response = sts.assume_role(
        RoleArn="your-role-arn",
        RoleSessionName="my-custom-session"
    )

    new_session = boto3.Session(aws_access_key_id=response['Credentials']['AccessKeyId'],
                                aws_secret_access_key=response['Credentials']['SecretAccessKey'],
                                aws_session_token=response['Credentials']['SessionToken'])

    return new_session.client("eks")


# Instance eks_client
if is_local:
    eks_client = session.client("eks")
else:
    eks_client = client_assuming_role(session)

# Cluster details
cluster = eks_client.describe_cluster(name=cluster_name)
cluster_cert = cluster["cluster"]["certificateAuthority"]["data"]
cluster_ep = cluster["cluster"]["endpoint"]
cluster_arn = cluster["cluster"]["arn"]

# build the cluster config hash
cluster_config = {
    "apiVersion": "v1",
    "kind": "Config",
    "clusters": [
        {
            "cluster": {
                "server": str(cluster_ep),
                "certificate-authority-data": str(cluster_cert)
            },
            "name": str(cluster_arn),
        }
    ],
    "contexts": [
        {
            "context": {
                "cluster": str(cluster_arn),
                "user": str(cluster_arn),
            },
            "name": str(cluster_arn),
        }
    ],
    "current-context": str(cluster_arn),
    "preferences": {},
    "users": [
        {
            "name": str(cluster_arn),
            "user": {
                "exec": {
                    "apiVersion": "client.authentication.k8s.io/v1beta1",
                    "command": "aws",
                    "args": [
                        "--region",
                        region,
                        "eks",
                        "get-token",
                        "--cluster-name",
                        cluster_name,
                        "--output",
                        "json"
                    ],
                }
            }
        }
    ]
}

# Write in YAML.
config_text = yaml.dump(cluster_config, default_flow_style=False)
open(config_output_file, "w").write(config_text)

print(f"Kubeconfig created for {cluster_name} in {config_output_file}")