Add API endpoint for getting server resource utilization, closes #900

This endpoint is throttled to 15 requests per minute to avoid destroying the daemon since clients can use it.

app/Http/Controllers/Api/Client/Servers/ResourceUtilizationController.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Pterodactyl\Http\Controllers\Api\Client\Servers;
+
+use Pterodactyl\Models\Server;
+use Pterodactyl\Transformers\Api\Client\StatsTransformer;
+use Pterodactyl\Http\Controllers\Api\Client\ClientApiController;
+use Pterodactyl\Http\Requests\Api\Client\Servers\GetServerRequest;
+
+class ResourceUtilizationController extends ClientApiController
+{
+    /**
+     * Return the current resource utilization for a server.
+     *
+     * @param \Pterodactyl\Http\Requests\Api\Client\Servers\GetServerRequest $request
+     * @return array
+     */
+    public function index(GetServerRequest $request): array
+    {
+        return $this->fractal->item($request->getModel(Server::class))
+            ->transformWith($this->getTransformer(StatsTransformer::class))
+            ->toArray();
+    }
+}

app/Transformers/Api/Client/StatsTransformer.php

@@ -0,0 +1,88 @@
+<?php
+
+namespace Pterodactyl\Transformers\Api\Client;
+
+use Pterodactyl\Models\Server;
+use Pterodactyl\Contracts\Repository\Daemon\ServerRepositoryInterface;
+
+class StatsTransformer extends BaseClientTransformer
+{
+    /**
+     * @var \Pterodactyl\Contracts\Repository\Daemon\ServerRepositoryInterface
+     */
+    private $repository;
+
+    /**
+     * Perform dependency injection.
+     *
+     * @param \Pterodactyl\Contracts\Repository\Daemon\ServerRepositoryInterface $repository
+     */
+    public function handle(ServerRepositoryInterface $repository)
+    {
+        $this->repository = $repository;
+    }
+
+    /**
+     * @return string
+     */
+    public function getResourceName(): string
+    {
+        return 'stats';
+    }
+
+    /**
+     * Transform stats from the daemon into a result set that can be used in
+     * the client API.
+     *
+     * @param \Pterodactyl\Models\Server $model
+     * @return array
+     */
+    public function transform(Server $model)
+    {
+        try {
+            $stats = $this->repository->setServer($model)->details();
+        } catch (RequestException $exception) {
+            throw new DaemonConnectionException($exception);
+        }
+
+        $object = json_decode($stats->getBody()->getContents());
+
+        return [
+            'state' => $this->transformState(object_get($object, 'status', 0)),
+            'memory' => [
+                'current' => round(object_get($object, 'proc.memory.total', 0) / 1024 / 1024),
+                'limit' => floatval($model->memory),
+            ],
+            'cpu' => [
+                'current' => object_get($object, 'proc.cpu.total', 0),
+                'cores' => object_get($object, 'proc.cpu.cores', []),
+                'limit' => floatval($model->cpu),
+            ],
+            'disk' => [
+                'current' => round(object_get($object, 'proc.disk.used', 0)),
+                'limit' => floatval($model->disk),
+            ],
+        ];
+    }
+
+    /**
+     * Transform the state returned by the daemon into a human readable string.
+     *
+     * @param int $state
+     * @return string
+     */
+    private function transformState(int $state): string
+    {
+        switch ($state) {
+            case 1:
+                return 'on';
+            case 2:
+                return 'starting';
+            case 3:
+                return 'stopping';
+            case 0:
+            default:
+                return 'off';
+        }
+    }
+}

routes/api-client.php

@@ -22,6 +22,9 @@ Route::get('/', 'ClientController@index')->name('api.client.index');
 */
 Route::group(['prefix' => '/servers/{server}', 'middleware' => [AuthenticateClientAccess::class]], function () {
     Route::get('/', 'Servers\ServerController@index')->name('api.client.servers.view');
+    Route::get('/utilization', 'Servers\ResourceUtilizationController@index')
+        ->middleware(['throttle:15,1'])
+        ->name('api.client.servers.resources');
 
     Route::post('/command', 'Servers\CommandController@index')->name('api.client.servers.command');
     Route::post('/power', 'Servers\PowerController@index')->name('api.client.servers.power');