Return GraphImage to include more metadata (#14307)

* Return GraphImage to include more metadata
Allows things like including title.
Implements __toString for backwards compatability
getImageData to allow controlling the output through flags

* Style and Lint

LibreNMS/Data/Graphing/GraphImage.php

@@ -0,0 +1,91 @@
+<?php
+/**
+ * GraphImage.php
+ *
+ * Wrapper around a graph image to include metadata and control output format
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ * @link       https://www.librenms.org
+ *
+ * @copyright  2022 Tony Murray
+ * @author     Tony Murray <murraytony@gmail.com>
+ */
+
+namespace LibreNMS\Data\Graphing;
+
+class GraphImage
+{
+    /**
+     * @var string
+     */
+    private $type;
+    /**
+     * @var string
+     */
+    private $title;
+    /**
+     * @var string
+     */
+    private $data;
+
+    public function __construct(string $type, string $title, string $data)
+    {
+        $this->type = $type;
+        $this->title = $title;
+        $this->data = $data;
+    }
+
+    public function title(): string
+    {
+        return $this->title;
+    }
+
+    public function data(): string
+    {
+        return $this->data;
+    }
+
+    public function base64(): string
+    {
+        return base64_encode($this->data);
+    }
+
+    public function inline(): string
+    {
+        return 'data:' . $this->imageType() . ';base64,' . $this->base64();
+    }
+
+    public function fileExtension(): string
+    {
+        switch ($this->imageType()) {
+            case 'image/svg+xml':
+                return 'svg';
+            case 'image/png':
+                // fallthrough
+            default:
+                return 'png';
+        }
+    }
+
+    public function imageType(): string
+    {
+        return $this->type;
+    }
+
+    public function __toString()
+    {
+        return $this->data();
+    }
+}

LibreNMS/Util/Graph.php

@@ -29,6 +29,7 @@ use App\Facades\DeviceCache;
 use App\Models\Device;
 use Illuminate\Support\Facades\Auth;
 use LibreNMS\Config;
+use LibreNMS\Data\Graphing\GraphImage;
 use LibreNMS\Exceptions\RrdGraphException;
 use Rrd;
 
@@ -36,19 +37,66 @@ class Graph
 {
     const BASE64_OUTPUT = 1; // BASE64 encoded image data
     const INLINE_BASE64 = 2; // img src inline base64 image
-    const COMMAND_ONLY = 4; // just print the command
+    const IMAGE_PNG = 4; // img src inline base64 image
+    const IMAGE_SVG = 8; // img src inline base64 image
 
     /**
-     * Fetch a graph image (as string) based on the given $vars
-     * Optionally, override the output format to base64
+     * Convenience helper to specify desired image output
      *
      * @param  array|string  $vars
-     * @param  int  $flags  Flags for controlling graph generating options.
+     * @param  int  $flags
      * @return string
+     */
+    public static function getImageData($vars, int $flags = 0): string
+    {
+        if ($flags & self::IMAGE_PNG) {
+            $vars['graph_type'] = 'png';
+        }
+
+        if ($flags & self::IMAGE_SVG) {
+            $vars['graph_type'] = 'svg';
+        }
+
+        if ($flags & self::INLINE_BASE64) {
+            return self::getImage($vars)->inline();
+        }
+
+        if ($flags & self::BASE64_OUTPUT) {
+            return self::getImage($vars)->base64();
+        }
+
+        return self::getImage($vars)->data();
+    }
+
+    /**
+     * Fetch a GraphImage based on the given $vars
+     * Catches errors generated and always returns GraphImage
+     *
+     * @param  array|string  $vars
+     * @return GraphImage
+     */
+    public static function getImage($vars): GraphImage
+    {
+        try {
+            return self::get($vars);
+        } catch (RrdGraphException $e) {
+            if (Debug::isEnabled()) {
+                throw $e;
+            }
+
+            return new GraphImage(self::imageType(), 'Error', $e->generateErrorImage());
+        }
+    }
+
+    /**
+     * Fetch a GraphImage based on the given $vars
+     *
+     * @param  array|string  $vars
+     * @return GraphImage
      *
      * @throws \LibreNMS\Exceptions\RrdGraphException
      */
-    public static function get($vars, int $flags = 0): string
+    public static function get($vars): GraphImage
     {
         define('IGNORE_ERRORS', true);
         chdir(base_path());
@@ -80,13 +128,11 @@ class Graph
         $title = $vars['title'] ?? '';
         $vertical = $vars['vertical'] ?? '';
         $legend = $vars['legend'] ?? false;
-        $output = $vars['output'] ?? 'default';
         $from = parse_at_time($vars['from'] ?? '-1d');
         $to = empty($vars['to']) ? time() : parse_at_time($vars['to']);
         $period = ($to - $from);
         $prev_from = ($from - $period);
         $graph_image_type = $vars['graph_type'] ?? Config::get('webui.graph_type');
-        Config::set('webui.graph_type', $graph_image_type); // set in case accessed elsewhere
         $rrd_options = '';
         $rrd_filename = null;
 
@@ -113,26 +159,6 @@ class Graph
             }
         }
 
-        // command output requested
-        if ($flags & self::COMMAND_ONLY) {
-            $cmd_output = "<div class='infobox'>";
-            $cmd_output .= "<p style='font-size: 16px; font-weight: bold;'>RRDTool Command</p>";
-            $cmd_output .= "<pre class='rrd-pre'>";
-            $cmd_output .= escapeshellcmd('rrdtool ' . Rrd::buildCommand('graph', Config::get('temp_dir') . '/' . strgen(), $rrd_options));
-            $cmd_output .= '</pre>';
-            try {
-                $cmd_output .= Rrd::graph($rrd_options);
-            } catch (RrdGraphException $e) {
-                $cmd_output .= "<p style='font-size: 16px; font-weight: bold;'>RRDTool Output</p>";
-                $cmd_output .= "<pre class='rrd-pre'>";
-                $cmd_output .= $e->getMessage();
-                $cmd_output .= '</pre>';
-            }
-            $cmd_output .= '</div>';
-
-            return $cmd_output;
-        }
-
         if (empty($rrd_options)) {
             throw new RrdGraphException('Graph Definition Error', 'Def Error', $width, $height);
         }
@@ -141,16 +167,7 @@ class Graph
         try {
             $image_data = Rrd::graph($rrd_options);
 
-            // output the graph int the desired format
-            if (Debug::isEnabled()) {
-                return '<img src="data:' . self::imageType($graph_image_type) . ';base64,' . base64_encode($image_data) . '" alt="graph" />';
-            } elseif ($flags & self::BASE64_OUTPUT || $output == 'base64') {
-                return base64_encode($image_data);
-            } elseif ($flags & self::INLINE_BASE64 || $output == 'inline-base64') {
-                return 'data:' . self::imageType($graph_image_type) . ';base64,' . base64_encode($image_data);
-            }
-
-            return $image_data; // raw data
+            return new GraphImage(self::imageType($graph_image_type), $title ?? $graph_title, $image_data);
         } catch (RrdGraphException $e) {
             // preserve original error if debug is enabled, otherwise make it a little more user friendly
             if (Debug::isEnabled()) {
@@ -237,11 +254,15 @@ class Graph
     /**
      * Get the http content type of the image
      *
-     * @param  string  $type  svg or png
+     * @param  string|null  $type  svg or png
      * @return string
      */
-    public static function imageType(string $type): string
+    public static function imageType(?string $type = null): string
     {
+        if ($type === null) {
+            $type = Config::get('webui.graph_type');
+        }
+
         return $type === 'svg' ? 'image/svg+xml' : 'image/png';
     }
 

LibreNMS/Util/Mail.php

@@ -91,7 +91,7 @@ class Mail
                 $mail->WordWrap = 76;
                 $mail->Body = $message;
                 if ($embedGraphs ?? Config::get('email_attach_graphs')) {
-                    self::embedGraphs($mail);
+                    self::embedGraphs($mail, $html);
                 }
                 if ($html) {
                     $mail->isHTML();
@@ -132,32 +132,37 @@ class Mail
     /**
      * Search for generated graph links, generate them, attach them to the email and update the url to a cid link
      */
-    private static function embedGraphs(PHPMailer $mail): void
+    private static function embedGraphs(PHPMailer $mail, bool $html = false): void
     {
         $body = $mail->Body;
 
         // search for generated graphs
-        preg_match_all('/ class=\"librenms-graph\" src=\"(.*?)\"/', $body, $match);
+        preg_match_all('#<img class=\"librenms-graph\" src=\"(.*?)\" ?/?>#', $body, $matches);
 
-        foreach (array_values(array_unique($match[1])) as $attachment_id => $url) {
+        $count = 0;
+        foreach (array_combine($matches[1], $matches[0]) as $url => $tag) {
             try {
-                $cid = "graph$attachment_id";
+                $cid = 'graph' . ++$count;
 
-                // fetch image, do not debug as it will return the wrong format.
-                $prev = Debug::isEnabled();
-                Debug::set(false);
-                $image = Graph::get(Url::parseLegacyPathVars($url));
-                Debug::set($prev);
+                // fetch image data
+                $image = Graph::getImage($url);
 
                 // attach image
-                if (Config::get('webui.graph_type') == 'svg') {
-                    $mail->addStringEmbeddedImage($image, $cid, "$cid.svg", PHPMailer::ENCODING_BASE64, 'image/svg+xml');
-                } else {
-                    $mail->addStringEmbeddedImage($image, $cid, "$cid.png", PHPMailer::ENCODING_BASE64, 'image/png');
-                }
+                $fileName = substr(Clean::fileName($image->title() ?: $cid), 0, 250);
+                $mail->addStringEmbeddedImage(
+                    $image->data(),
+                    $cid,
+                    $fileName . '.' . $image->fileExtension(),
+                    PHPMailer::ENCODING_BASE64,
+                    $image->imageType()
+                );
 
-                // update image tag to link to attached image
+                // update image tag to link to attached image, or just the image name
+                if ($html) {
                     $body = str_replace($url, "cid:$cid", $body);
+                } else {
+                    $body = str_replace($tag, "[$fileName]", $body);
+                }
             } catch (RrdGraphException|\PHPMailer\PHPMailer\Exception $e) {
                 report($e);
             }

app/Http/Controllers/GraphController.php

@@ -18,25 +18,35 @@ class GraphController extends Controller
     public function __invoke(Request $request, string $path = ''): Response
     {
         $vars = array_merge(Url::parseLegacyPathVars($request->path()), $request->except(['username', 'password']));
-        $vars['graph_type'] = $vars['graph_type'] ?? Config::get('webui.graph_type');
+        $output = $vars['graph_type'] ?? Config::get('webui.graph_type', 'default');
 
         if (\Auth::check()) {
             // only allow debug for logged in users
             Debug::set(! empty($vars['debug']));
         }
 
+        try {
+            $graph = Graph::get($vars);
+
+            if (Debug::isEnabled()) {
+                return response('<img src="' . $graph->inline() . '" alt="graph" />');
+            }
+
             $headers = [
-            'Content-type' => Graph::imageType($vars['graph_type']),
+                'Content-type' => $graph->imageType(),
             ];
 
-        try {
-            return response(Graph::get($vars), 200, Debug::isEnabled() ? [] : $headers);
+            if ($output == 'base64') {
+                return response($graph, 200, $headers);
+            }
+
+            return response($graph->data(), 200, $headers);
         } catch (RrdGraphException $e) {
             if (Debug::isEnabled()) {
                 throw $e;
             }
 
-            return response($e->generateErrorImage(), 500, $headers);
+            return response($e->generateErrorImage(), 500, ['Content-type' => Graph::imageType()]);
         }
     }
 }

app/Providers/AppServiceProvider.php

@@ -81,7 +81,7 @@ class AppServiceProvider extends ServiceProvider
         });
 
         Blade::directive('graphImage', function ($vars, $flags = 0) {
-            return "<?php echo \LibreNMS\Util\Graph::get($vars, $flags); ?>";
+            return "<?php echo \LibreNMS\Util\Graph::getImageData($vars, $flags); ?>";
         });
     }