Merge pull request #35 from renoki-co/feature/scaling

[feature] Scaling for StatefulSet & Deployment

Author: rennokki

docs/kinds/Deployment.md

@@ -111,6 +111,24 @@ foreach ($dep->getPods() as $pod) {
 }
 ```
 
+### Scaling
+
+The Scaling API is available via a `K8sScale` resource:
+
+```php
+$scaler = $dep->scaler();
+
+$scaler->setReplicas(3)->update(); // autoscale the Deployment to 3 replicas
+```
+
+Shorthand, you can use `scale()` directly from the Deployment
+
+```php
+$scaler = $dep->scale(3);
+
+$pods = $dep->getPods(); // Expecting 3 pods
+```
+
 ### Deployment Status
 
 The Status API is available to be accessed for fresh instances:

docs/kinds/StatefulSet.md

@@ -127,6 +127,24 @@ foreach ($sts->getPods() as $pod) {
 }
 ```
 
+### Scaling
+
+The Scaling API is available via a `K8sScale` resource:
+
+```php
+$scaler = $sts->scaler();
+
+$scaler->setReplicas(3)->update(); // autoscale the StatefulSet to 3 replicas
+```
+
+Shorthand, you can use `scale()` directly from the StatefulSet
+
+```php
+$scaler = $sts->scale(3);
+
+$pods = $sts->getPods(); // Expecting 3 pods
+```
+
 ### StatefulSet Status
 
 The Status API is available to be accessed for fresh instances:

src/Contracts/Scalable.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace RenokiCo\PhpK8s\Contracts;
+
+interface Scalable
+{
+    /**
+     * Get the path, prefixed by '/', that points to the resource scale.
+     *
+     * @return string
+     */
+    public function resourceScalePath(): string;
+}

src/Kinds/K8sDeployment.php

@@ -4,17 +4,19 @@
 
 use RenokiCo\PhpK8s\Contracts\InteractsWithK8sCluster;
 use RenokiCo\PhpK8s\Contracts\Podable;
+use RenokiCo\PhpK8s\Contracts\Scalable;
 use RenokiCo\PhpK8s\Contracts\Watchable;
+use RenokiCo\PhpK8s\Traits\CanScale;
 use RenokiCo\PhpK8s\Traits\HasAnnotations;
 use RenokiCo\PhpK8s\Traits\HasLabels;
 use RenokiCo\PhpK8s\Traits\HasPods;
 use RenokiCo\PhpK8s\Traits\HasSelector;
 use RenokiCo\PhpK8s\Traits\HasSpec;
 use RenokiCo\PhpK8s\Traits\HasTemplate;
 
-class K8sDeployment extends K8sResource implements InteractsWithK8sCluster, Podable, Watchable
+class K8sDeployment extends K8sResource implements InteractsWithK8sCluster, Podable, Scalable, Watchable
 {
-    use HasAnnotations, HasLabels, HasPods, HasSelector, HasSpec, HasTemplate;
+    use CanScale, HasAnnotations, HasLabels, HasPods, HasSelector, HasSpec, HasTemplate;
 
     /**
      * The resource Kind parameter.
@@ -98,6 +100,16 @@ public function resourceWatchPath(): string
         return "/apis/{$this->getApiVersion()}/watch/namespaces/{$this->getNamespace()}/deployments/{$this->getIdentifier()}";
     }
 
+    /**
+     * Get the path, prefixed by '/', that points to the resource scale.
+     *
+     * @return string
+     */
+    public function resourceScalePath(): string
+    {
+        return "/apis/{$this->getApiVersion()}/namespaces/{$this->getNamespace()}/deployments/{$this->getIdentifier()}/scale";
+    }
+
     /**
      * Get the selector for the pods that are owned by this resource.
      *

src/Kinds/K8sResource.php

@@ -6,6 +6,7 @@
 use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Contracts\Support\Jsonable;
 use RenokiCo\PhpK8s\Contracts\Loggable;
+use RenokiCo\PhpK8s\Contracts\Scalable;
 use RenokiCo\PhpK8s\Contracts\Watchable;
 use RenokiCo\PhpK8s\Exceptions\KubernetesAPIException;
 use RenokiCo\PhpK8s\Exceptions\KubernetesWatchException;
@@ -728,4 +729,31 @@ public function watchContainerLogsByName(string $name, string $container, Closur
     {
         return $this->whereName($name)->watchContainerLogs($container, $callback, $query);
     }
+
+    /**
+     * Get a specific resource scaling data.
+     *
+     * @return \RenokiCo\PhpK8s\Kinds\K8sScale
+     */
+    public function scaler(): K8sScale
+    {
+        if (! $this instanceof Scalable) {
+            throw new KubernetesScalingException(
+                'The resource '.get_class($this).' does not support scaling.'
+            );
+        }
+
+        $scaler = $this->cluster
+            ->setResourceClass(K8sScale::class)
+            ->runOperation(
+                KubernetesCluster::GET_OP,
+                $this->resourceScalePath(),
+                $this->toJsonPayload(),
+                ['pretty' => 1]
+            );
+
+        $scaler->setScalableResource($this);
+
+        return $scaler;
+    }
 }

src/Kinds/K8sScale.php

@@ -0,0 +1,93 @@
+<?php
+
+namespace RenokiCo\PhpK8s\Kinds;
+
+use RenokiCo\PhpK8s\Contracts\InteractsWithK8sCluster;
+use RenokiCo\PhpK8s\Traits\HasSpec;
+
+class K8sScale extends K8sResource implements InteractsWithK8sCluster
+{
+    use HasSpec;
+
+    /**
+     * The resource Kind parameter.
+     *
+     * @var null|string
+     */
+    protected static $kind = 'Scale';
+
+    /**
+     * The original scalable resource for this scale.
+     *
+     * @var \RenokiCo\PhpK8s\Kinds\K8sResource
+     */
+    protected $resource;
+
+    /**
+     * Wether the resource has a namespace.
+     *
+     * @var bool
+     */
+    protected static $namespaceable = true;
+
+    /**
+     * The default version for the resource.
+     *
+     * @var string
+     */
+    protected static $stableVersion = 'autoscaling/v1';
+
+    /**
+     * Get the path, prefixed by '/', that points to the resources list.
+     *
+     * @return string
+     */
+    public function allResourcesPath(): string
+    {
+        return '';
+    }
+
+    /**
+     * Get the path, prefixed by '/', that points to the specific resource.
+     *
+     * @return string
+     */
+    public function resourcePath(): string
+    {
+        return $this->resource->resourceScalePath();
+    }
+
+    /**
+     * Set the desired replicas for the scale.
+     *
+     * @param  int  $replicas
+     * @return $this
+     */
+    public function setReplicas(int $replicas)
+    {
+        return $this->setSpec('replicas', $replicas);
+    }
+
+    /**
+     * Get the defined replicas for the scale.
+     *
+     * @return int
+     */
+    public function getReplicas(): int
+    {
+        return $this->getSpec('replicas', 0);
+    }
+
+    /**
+     * Set the original scalable resource for this scale.
+     *
+     * @param  \RenokiCo\PhpK8s\Kinds\K8sResource  $resource
+     * @return $this
+     */
+    public function setScalableResource(K8sResource $resource)
+    {
+        $this->resource = $resource;
+
+        return $this;
+    }
+}

src/Kinds/K8sStatefulSet.php

@@ -4,17 +4,19 @@
 
 use RenokiCo\PhpK8s\Contracts\InteractsWithK8sCluster;
 use RenokiCo\PhpK8s\Contracts\Podable;
+use RenokiCo\PhpK8s\Contracts\Scalable;
 use RenokiCo\PhpK8s\Contracts\Watchable;
+use RenokiCo\PhpK8s\Traits\CanScale;
 use RenokiCo\PhpK8s\Traits\HasAnnotations;
 use RenokiCo\PhpK8s\Traits\HasLabels;
 use RenokiCo\PhpK8s\Traits\HasPods;
 use RenokiCo\PhpK8s\Traits\HasSelector;
 use RenokiCo\PhpK8s\Traits\HasSpec;
 use RenokiCo\PhpK8s\Traits\HasTemplate;
 
-class K8sStatefulSet extends K8sResource implements InteractsWithK8sCluster, Podable, Watchable
+class K8sStatefulSet extends K8sResource implements InteractsWithK8sCluster, Podable, Scalable, Watchable
 {
-    use HasAnnotations, HasLabels, HasPods, HasSelector, HasSpec, HasTemplate;
+    use CanScale, HasAnnotations, HasLabels, HasPods, HasSelector, HasSpec, HasTemplate;
 
     /**
      * The resource Kind parameter.
@@ -159,6 +161,16 @@ public function resourceWatchPath(): string
         return "/apis/{$this->getApiVersion()}/watch/namespaces/{$this->getNamespace()}/statefulsets/{$this->getIdentifier()}";
     }
 
+    /**
+     * Get the path, prefixed by '/', that points to the resource scale.
+     *
+     * @return string
+     */
+    public function resourceScalePath(): string
+    {
+        return "/apis/{$this->getApiVersion()}/namespaces/{$this->getNamespace()}/statefulsets/{$this->getIdentifier()}/scale";
+    }
+
     /**
      * Get the selector for the pods that are owned by this resource.
      *

src/Traits/CanScale.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace RenokiCo\PhpK8s\Traits;
+
+trait CanScale
+{
+    /**
+     * Scale the current resource to a specific number of replicas.
+     *
+     * @param  int  $replicas
+     * @return \RenokiCo\PhpK8s\Kinds\K8sScale
+     */
+    public function scale(int $replicas)
+    {
+        $scaler = $this->scaler();
+
+        $scaler->setReplicas($replicas)->update();
+
+        return $scaler;
+    }
+}

src/Traits/HasPods.php

@@ -22,7 +22,7 @@ public function getPods(array $query = ['pretty' => 1])
             ->all(array_merge(['labelSelector' => $labelSelector], $query));
     }
 
-     /**
+    /**
      * Check if all scheduled pods are running.
      *
      * @return bool

tests/DeploymentTest.php

@@ -73,6 +73,7 @@ public function test_deployment_api_interaction()
         $this->runUpdateTests();
         $this->runWatchAllTests();
         $this->runWatchTests();
+        $this->runScalingTests();
         $this->runDeletionTests();
     }
 
@@ -236,4 +237,22 @@ public function runWatchTests()
 
         $this->assertTrue($watch);
     }
+
+    public function runScalingTests()
+    {
+        $dep = $this->cluster->getDeploymentByName('mysql');
+
+        $scaler = $dep->scale(2);
+
+        while ($dep->getReadyReplicasCount() < 2 || $scaler->getReplicas() < 2) {
+            dump("Awaiting for deployment {$dep->getName()} to scale to 2 replicas...");
+            $scaler->refresh();
+            $dep->refresh();
+            sleep(1);
+        }
+
+        $this->assertEquals(2, $dep->getReadyReplicasCount());
+        $this->assertEquals(2, $scaler->getReplicas());
+        $this->assertCount(2, $dep->getPods());
+    }
 }