keboola/k8s-client

Keboola K8S client library

1.0.1 2022-11-03 12:20 UTC

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,
]);

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.