Add basic support for OpenGraph header tags for public installs

Summary: Ref T13018. This is easy to get working roughly, at least, and seems reasonable.

Test Plan: Viewed page source, saw tags. Custom header logo still worked. Pretty hard to debug against a local install since Disqus / debugger tools can't hit it, but I'll see what it looks like in production and tweak it if I got anything horribly wrong.

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13018

Differential Revision: https://secure.phabricator.com/D18780

src/applications/config/custom/PhabricatorCustomLogoConfigType.php

@@ -13,6 +13,39 @@ final class PhabricatorCustomLogoConfigType
     return idx($logo, 'wordmarkText');
   }
 
+  public static function getLogoURI(PhabricatorUser $viewer) {
+    $logo_uri = null;
+
+    $custom_header = self::getLogoImagePHID();
+    if ($custom_header) {
+      $cache = PhabricatorCaches::getImmutableCache();
+      $cache_key_logo = 'ui.custom-header.logo-phid.v3.'.$custom_header;
+      $logo_uri = $cache->getKey($cache_key_logo);
+
+      if (!$logo_uri) {
+        // NOTE: If the file policy has been changed to be restrictive, we'll
+        // miss here and just show the default logo. The cache will fill later
+        // when someone who can see the file loads the page. This might be a
+        // little spooky, see T11982.
+        $files = id(new PhabricatorFileQuery())
+          ->setViewer($viewer)
+          ->withPHIDs(array($custom_header))
+          ->execute();
+        $file = head($files);
+        if ($file) {
+          $logo_uri = $file->getViewURI();
+          $cache->setKey($cache_key_logo, $logo_uri);
+        }
+      }
+    }
+
+    if (!$logo_uri) {
+      $logo_uri = celerity_get_resource_uri('/rsrc/image/logo/light-eye.png');
+    }
+
+    return $logo_uri;
+  }
+
   public function validateOption(PhabricatorConfigOption $option, $value) {
     if (!is_array($value)) {
       throw new Exception(

src/view/page/PhabricatorStandardPageView.php

@@ -426,10 +426,11 @@ final class PhabricatorStandardPageView extends PhabricatorBarePageView
     }
 
     return hsprintf(
-      '%s%s%s',
+      '%s%s%s%s',
       parent::getHead(),
       $font_css,
-      $response->renderSingleResource('javelin-magical-init', 'phabricator'));
+      $response->renderSingleResource('javelin-magical-init', 'phabricator'),
+      $this->newOpenGraphTags());
   }
 
   public function setGlyph($glyph) {
@@ -911,4 +912,45 @@ final class PhabricatorStandardPageView extends PhabricatorBarePageView
     return $response;
   }
 
+  private function newOpenGraphTags() {
+    // If we don't allow public access, there's no point in emitting OpenGraph
+    // tags because external systems can't fetch pages.
+    if (!PhabricatorEnv::getEnvConfig('policy.allow-public')) {
+      return array();
+    }
+
+    $viewer = $this->getViewer();
+
+    $properties = array(
+      array(
+        'og:title',
+        $this->getTitle(),
+      ),
+      array(
+        'og:type',
+        'website',
+      ),
+      array(
+        'og:url',
+        PhabricatorEnv::getProductionURI($this->getRequest()->getRequestURI()),
+      ),
+      array(
+        'og:image',
+        PhabricatorCustomLogoConfigType::getLogoURI($viewer),
+      ),
+    );
+
+    $tags = array();
+    foreach ($properties as $property) {
+      $tags[] = phutil_tag(
+        'meta',
+        array(
+          'property' => $property[0],
+          'content' => $property[1],
+        ));
+    }
+
+    return $tags;
+  }
+
 }

src/view/page/menu/PhabricatorMainMenuView.php

@@ -262,35 +262,16 @@ final class PhabricatorMainMenuView extends AphrontView {
   }
 
   private function renderPhabricatorLogo() {
-    $custom_header = PhabricatorCustomLogoConfigType::getLogoImagePHID();
-
     $logo_style = array();
+
+    $custom_header = PhabricatorCustomLogoConfigType::getLogoImagePHID();
     if ($custom_header) {
-      $cache = PhabricatorCaches::getImmutableCache();
-      $cache_key_logo = 'ui.custom-header.logo-phid.v3.'.$custom_header;
+      $viewer = $this->getViewer();
+      $logo_uri = PhabricatorCustomLogoConfigType::getLogoURI($viewer);
 
-      $logo_uri = $cache->getKey($cache_key_logo);
-      if (!$logo_uri) {
-        // NOTE: If the file policy has been changed to be restrictive, we'll
-        // miss here and just show the default logo. The cache will fill later
-        // when someone who can see the file loads the page. This might be a
-        // little spooky, see T11982.
-        $files = id(new PhabricatorFileQuery())
-          ->setViewer($this->getViewer())
-          ->withPHIDs(array($custom_header))
-          ->execute();
-        $file = head($files);
-        if ($file) {
-          $logo_uri = $file->getViewURI();
-          $cache->setKey($cache_key_logo, $logo_uri);
-        }
-      }
-
-      if ($logo_uri) {
-        $logo_style[] = 'background-size: 40px 40px;';
-        $logo_style[] = 'background-position: 0 0;';
-        $logo_style[] = 'background-image: url('.$logo_uri.')';
-      }
+      $logo_style[] = 'background-size: 40px 40px;';
+      $logo_style[] = 'background-position: 0 0;';
+      $logo_style[] = 'background-image: url('.$logo_uri.')';
     }
 
     $logo_node = phutil_tag(
@@ -300,7 +281,6 @@ final class PhabricatorMainMenuView extends AphrontView {
         'style' => implode(' ', $logo_style),
       ));
 
-
     $wordmark_text = PhabricatorCustomLogoConfigType::getLogoWordmark();
     if (!strlen($wordmark_text)) {
       $wordmark_text = pht('Phabricator');