keboola/k8s-client

Keboola K8S client library

2.1.0 2024-03-12 15:49 UTC

Requires

• php: ^8.2
• keboola/retry: ^0.5.1
• kubernetes/php-client: 1.26.10
• kubernetes/php-runtime: ^1.0.10

Requires (Dev)

• keboola/coding-standard: ^15.0
• phpstan/phpstan: ^1.9
• phpstan/phpstan-phpunit: ^1.1
• phpunit/phpunit: ^9.5
• sempro/phpunit-pretty-print: ^1.4
• symfony/dotenv: ^6.2
• symfony/filesystem: ^6.1

MIT

• Keboola

README

High-level K8S client library. It is based on kubernetes/php-client library, but enhances it in many ways:

• support connection to multiple clusters
• automatic handling of result type (you don't need to check if the result is what you expect, Status or something else)
• integrated retries in case of networking problems
• high-level operations like create multiple resources at once, waitWhileExists to wait while given resource exists etc.

Usage

To create a client, use one of provided client factories:

• GenericClientFacadeFactory if you have cluster credentials
• InClusterClientFacadeFactory if you run inside a Pod which has access to K8S API

<?php

use Keboola\K8sClient\ClientFacadeFactory\GenericClientFacadeFactory;
use Kubernetes\Model\Io\K8s\Api\Core\V1\Container;
use Kubernetes\Model\Io\K8s\Api\Core\V1\Pod;

$clientFactory = new GenericClientFacadeFactory($retryProxy, $logger);
$client = $clientFactory->createClusterClient(
    'https://api.k8s-cluster.example.com',
    'secret-token',
    'var/k8s/caCert.pem',
    'default'
);

$pod = new Pod([
    'metadata' => [
        'name' => 'my-pod',
    ],
    'spec' => [
        'restartPolicy' => 'Never',
        'containers' => [
            new Container([
                'name' => 'app',
                'image' => 'alpine',
                'command' => ['sh', '-c', 'echo hello; sleep 3; echo bye'],
            ]),
        ],
    ],
]);

// create the pod
$client->createModels([
    $pod,
]);

// wait for pod to finish
do {
    $pod = $client->pods()->getStatus($pod->metadata->name);

    if (in_array($pod->status->phase, ['Succeeded', 'Failed'], true)) {
        break;
    }

    sleep(1);
} while (true);

// check pod logs
$client->pods()->readLog($pod->metadata->name);

// delete the pod
$client->deleteModels([
    $pod,
]);

Development

Prerequisites:

• configured az and aws CLI tools (run az login and aws configure --profile keboola-dev-platform-services)
• installed terraform (https://www.terraform.io) and jq (https://stedolan.github.io/jq) to setup local env
• installed docker to run & develop the library

TL;DR:

export NAME_PREFIX= # your name/nickname to make your resource unique & recognizable

cat <<EOF > ./provisioning/local/terraform.tfvars
name_prefix = "${NAME_PREFIX}"
EOF

terraform -chdir=./provisioning/local init -backend-config="key=k8s-client/${NAME_PREFIX}.tfstate"
terraform -chdir=./provisioning/local apply
./provisioning/local/update-env.sh azure # or aws

docker compose run --rm dev composer install
docker compose run --rm dev composer ci

Implementing new API

Only few K8S APIs we needed are implement so far. To implement new API, do following:

• create API client wrapper in Keboola\K8sClient\ApiClient
  • this is a wrapper around kubernetes/php-client API class, takes care of handling results
• add the wrapper to KubernetesApiClientFacade
  • inject the kubernetes/php-client client through constructor
  • add support for the new resource to methods signatures
• update GenericClientFacadeFactory to provide new API class to KubernetesApiClientFacade

License

MIT licensed, see LICENSE file.