Support Graphite Web with HTTP basic authn

refs #36

application/controllers/ShowController.php

@@ -7,6 +7,7 @@ use Icinga\Exception\NotFoundError;
 use Icinga\Module\Graphite\GraphiteChart;
 use Icinga\Module\Graphite\GraphiteUtil;
 use Icinga\Module\Graphite\GraphiteWeb;
+use Icinga\Module\Graphite\GraphiteWebClient;
 use Icinga\Module\Graphite\GraphTemplate;
 use Icinga\Module\Graphite\TemplateStore;
 use Icinga\Web\Controller;
@@ -14,8 +15,6 @@ use Icinga\Web\Widget;
 
 class ShowController extends Controller
 {
-    protected $baseUrl;
-
     protected $graphiteWeb;
 
     protected $templates;
@@ -34,8 +33,7 @@ class ShowController extends Controller
     {
         $config = $this->Config();
         $this->templateStore = new TemplateStore();
-        $this->baseUrl = $this->Config()->get('graphite', 'web_url');
-        $graphite = $this->graphiteWeb = new GraphiteWeb($this->baseUrl);
+        $graphite = $this->graphiteWeb = new GraphiteWeb(GraphiteWebClient::getInstance());
         $this->template = $this->view->template = $this->loadTemplate();
         $this->params->shift('r');
     }

application/forms/ConfigForm.php

@@ -3,6 +3,7 @@
 namespace Icinga\Module\Graphite\Forms;
 
 use Icinga\Forms\ConfigForm as BaseConfigForm;
+use Icinga\Module\Graphite\Web\Form\Validator\HttpUserValidator;
 
 class ConfigForm extends BaseConfigForm
 {
@@ -14,15 +15,34 @@ class ConfigForm extends BaseConfigForm
 
     public function createElements(array $formData)
     {
-        $this->addElement(
-            'text',
-            'graphite_web_url',
-            array(
-                'required'      => true,
-                'label'         => $this->translate('Graphite Web URL'),
-                'description'   => $this->translate('URL to your Graphite Web'),
-                'validators'    => ['UrlValidator']
-            )
-        );
+        $this->addElements([
+            [
+                'text',
+                'graphite_web_url',
+                [
+                    'required'      => true,
+                    'label'         => $this->translate('Graphite Web URL'),
+                    'description'   => $this->translate('URL to your Graphite Web'),
+                    'validators'    => ['UrlValidator']
+                ]
+            ],
+            [
+                'text',
+                'graphite_web_user',
+                [
+                    'label'         => $this->translate('Graphite Web user'),
+                    'description'   => $this->translate('A user with access to your Graphite Web'),
+                    'validators'    => [new HttpUserValidator()]
+                ]
+            ],
+            [
+                'password',
+                'graphite_web_password',
+                [
+                    'label'         => $this->translate('Graphite Web password'),
+                    'description'   => $this->translate('The above user\'s password')
+                ]
+            ]
+        ]);
     }
 }

library/Graphite/GraphiteChart.php

@@ -95,27 +95,20 @@ class GraphiteChart
 
     public function getUrl()
     {
-        $urlPattern = '/^' . preg_quote(Url::fromPath('/'), '/') . '/';
         $url = Url::fromPath('/render', $this->getParams());
         $this->template->extendUrl($url, $this->metric, $this->vars);
         $url->getParams()->add('_ext', 'whatever.svg');
-        $url = preg_replace($urlPattern, $this->web->getBaseUrl() . '/', $url);
         return $url;
     }
 
     public function fetchImage()
     {
-        $options = array(
-            'http'=>array(
-            'method'=>"POST",
-            'header'=>
-                "Accept-language: en\r\n".
-                "Content-type: application/x-www-form-urlencoded\r\n",
-//                'content'=> $data
-            )
+        $url = $this->getUrl();
+        return $this->web->getClient()->request(
+            $url->getPath(),
+            $url->getParams(),
+            'POST',
+            ['Accept-language' => 'en', 'Content-type' => 'application/x-www-form-urlencoded']
         );
-
-        $context = stream_context_create($options);
-        return file_get_contents($this->getUrl(), false, $context);
     }
 }

library/Graphite/GraphiteWeb.php

@@ -13,20 +13,20 @@ use Icinga\Module\Graphite\GraphiteQuery;
 class GraphiteWeb
 {
     /**
-     * Graphite webapp base url
+     * HTTP interface to Graphite Web
      *
-     * @var string
+     * @var GraphiteWebClientInterface
      */
-    protected $baseUrl;
+    private $client;
 
     /**
      * Construct a new graphite webapp instance
      *
-     * @param $baseUrl string Graphite webapp base url
+     * @param   GraphiteWebClientInterface  $client HTTP interface to Graphite Web
      */
-    public function __construct($baseUrl)
+    public function __construct(GraphiteWebClientInterface $client)
     {
-        $this->baseUrl = $baseUrl;
+        $this->client = $client;
     }
 
     /**
@@ -40,13 +40,13 @@ class GraphiteWeb
     }
 
     /**
-     * Retrieve out base url
+     * Get {@link client}
      *
-     * @return string
+     * @return GraphiteWebClientInterface
      */
-    public function getBaseUrl()
+    public function getClient()
     {
-        return $this->baseUrl;
+        return $this->client;
     }
 
     /**
@@ -56,11 +56,7 @@ class GraphiteWeb
      */
     public function listMetrics($filter)
     {
-        $res = json_decode(
-            file_get_contents(
-                $this->baseUrl . '/metrics/expand?query=' . $filter
-            )
-        );
+        $res = json_decode($this->client->request('metrics/expand', ['query' => $filter]));
         natsort($res->results);
         return array_values($res->results);
     }

library/Graphite/GraphiteWebClient.php

@@ -0,0 +1,67 @@
+<?php
+
+namespace Icinga\Module\Graphite;
+
+use Icinga\Application\Config;
+use Icinga\Exception\ConfigurationError;
+use Icinga\Module\Graphite\Pattern\Singleton;
+use Icinga\Web\Url;
+use Icinga\Web\UrlParams;
+
+class GraphiteWebClient implements GraphiteWebClientInterface
+{
+    use Singleton;
+
+    /**
+     * Base URL as configured
+     *
+     * @var string
+     */
+    private $baseUrl;
+
+    /**
+     * Default headers
+     *
+     * @var string[string]
+     */
+    private $baseHeaders;
+
+    public function request($url, $params = null, $method = 'GET', array $headers = [], $body = null)
+    {
+        $httpOptions = ['method' => $method, 'header' => ''];
+        foreach (array_merge($this->baseHeaders, $headers) as $header => $headerValue) {
+            $httpOptions['header'] .= "$header: $headerValue\r\n";
+        }
+
+        if ($body !== null) {
+            $httpOptions['content'] = $body;
+        }
+
+        $url = Url::fromPath($this->baseUrl . ltrim($url, '/'));
+        if ($params !== null) {
+            $url->setParams($params);
+        }
+
+        // TODO(ak): use our CurlClient (one nice day)
+        return file_get_contents($url->getAbsoluteUrl(), false, stream_context_create(['http' => $httpOptions]));
+    }
+
+    private function init()
+    {
+        $config = Config::module('graphite');
+        $graphite = $config->getSection('graphite');
+        $baseUrl = $graphite->web_url;
+        if ($baseUrl === null) {
+            throw new ConfigurationError('Missing graphite.web_url in "%s"', $config->getConfigFile());
+        }
+
+        $this->baseUrl = rtrim($baseUrl, '/') . '/';
+
+        $this->baseHeaders = ['User-Agent' => 'icingaweb2-module-graphite'];
+        if (isset($graphite->web_user) && isset($graphite->web_password)) {
+            $this->baseHeaders['Authorization'] = 'Basic ' . base64_encode(
+                "{$graphite->web_user}:{$graphite->web_password}"
+            );
+        }
+    }
+}

library/Graphite/GraphiteWebClientInterface.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Icinga\Module\Graphite;
+
+use Icinga\Application\Config;
+use Icinga\Exception\ConfigurationError;
+use Icinga\Module\Graphite\Pattern\Singleton;
+use Icinga\Web\Url;
+use Icinga\Web\UrlParams;
+
+/**
+ *  HTTP interface to Graphite Web
+ */
+interface GraphiteWebClientInterface
+{
+    /**
+     * Send an HTTP request to the configured Graphite Web and return the response's body
+     *
+     * @param   string                      $url
+     * @param   UrlParams|string[string]    $params
+     * @param   string                      $method
+     * @param   string[string]              $headers
+     * @param   string                      $body
+     *
+     * @return  string
+     */
+    public function request($url, $params = null, $method = 'GET', array $headers = [], $body = null);
+}

library/Graphite/Pattern/Singleton.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace Icinga\Module\Graphite\Pattern;
+
+use Exception;
+
+/**
+ * Everything needed for a singleton class
+ */
+trait Singleton
+{
+    /**
+     * The only instance of a class
+     *
+     * @var static
+     */
+    private static $instance;
+
+    /**
+     * Initialize and return {@link instance}
+     *
+     * @return static
+     */
+    public static function getInstance()
+    {
+        if (self::$instance === null) {
+            self::$instance = new static();
+        }
+
+        return self::$instance;
+    }
+
+    /**
+     * Constructor
+     */
+    final private function __construct()
+    {
+        $this->init();
+    }
+
+    /**
+     * Ensure that no one can clone the object
+     */
+    final private function __clone()
+    {
+        throw new Exception('Won\'t clone a singleton');
+    }
+
+    /**
+     * Initializer
+     *
+     * May be overridden.
+     */
+    private function init()
+    {
+    }
+}

library/Graphite/Web/Form/Validator/HttpUserValidator.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace Icinga\Module\Graphite\Web\Form\Validator;
+
+use Zend_Validate_Abstract;
+
+/**
+ * Validates http basic authn user names
+ *
+ * TODO(ak): move to Icinga Web 2
+ */
+class HttpUserValidator extends Zend_Validate_Abstract
+{
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        $this->_messageTemplates = ['HAS_COLON' => mt('graphite', 'The username must not contain colons.')];
+    }
+
+    public function isValid($value)
+    {
+        $hasColon = false !== strpos($value, ':');
+        if ($hasColon) {
+            $this->_error('HAS_COLON');
+        }
+        return ! $hasColon;
+    }
+}