Add a PDF document "rendering" engine

Summary:
Depends on D19251. Ref T13105. This adds rendering engine support for PDFs.

It doesn't actually render them, it just renders a link which you can click to view them in a new window. This is much easier than actually rendering them inline and at least 95% as good most of the time (and probably more-than-100%-as-good some of the time).

This makes PDF a viewable MIME type by default and adds a narrow CSP exception for it. See also T13112.

Test Plan:
  - Viewed PDFs in Files, got a link to view them in a new tab.
  - Clicked the link in Safari, Chrome, and Firefox; got inline PDFs.
  - Verified primary CSP is still `object-src 'none'` with `curl ...`.
  - Interacted with the vanilla lightbox element to check that it still works.

Maniphest Tasks: T13105

Differential Revision: https://secure.phabricator.com/D19252

resources/celerity/map.php

@@ -9,7 +9,7 @@ return array(
   'names' => array(
     'conpherence.pkg.css' => 'e68cf1fa',
     'conpherence.pkg.js' => '15191c65',
-    'core.pkg.css' => 'afe29a6c',
+    'core.pkg.css' => '2d73b2f3',
     'core.pkg.js' => 'b9b4a943',
     'differential.pkg.css' => '113e692c',
     'differential.pkg.js' => 'f6d809c0',
@@ -112,7 +112,7 @@ return array(
     'rsrc/css/application/tokens/tokens.css' => '3d0f239e',
     'rsrc/css/application/uiexample/example.css' => '528b19de',
     'rsrc/css/core/core.css' => '62fa3ace',
-    'rsrc/css/core/remarkup.css' => '97dc3523',
+    'rsrc/css/core/remarkup.css' => 'b375546d',
     'rsrc/css/core/syntax.css' => 'cae95e89',
     'rsrc/css/core/z-index.css' => '9d8f7c4b',
     'rsrc/css/diviner/diviner-shared.css' => '896f1d43',
@@ -168,7 +168,7 @@ return array(
     'rsrc/css/phui/phui-object-box.css' => '9cff003c',
     'rsrc/css/phui/phui-pager.css' => 'edcbc226',
     'rsrc/css/phui/phui-pinboard-view.css' => '2495140e',
-    'rsrc/css/phui/phui-property-list-view.css' => '94a14381',
+    'rsrc/css/phui/phui-property-list-view.css' => '47018d3c',
     'rsrc/css/phui/phui-remarkup-preview.css' => '54a34863',
     'rsrc/css/phui/phui-segment-bar-view.css' => 'b1d1b892',
     'rsrc/css/phui/phui-spacing.css' => '042804d6',
@@ -780,7 +780,7 @@ return array(
     'phabricator-object-selector-css' => '85ee8ce6',
     'phabricator-phtize' => 'd254d646',
     'phabricator-prefab' => '77b0ae28',
-    'phabricator-remarkup-css' => '97dc3523',
+    'phabricator-remarkup-css' => 'b375546d',
     'phabricator-search-results-css' => '505dd8cf',
     'phabricator-shaped-request' => '7cbe244b',
     'phabricator-slowvote-css' => 'a94b7230',
@@ -850,7 +850,7 @@ return array(
     'phui-oi-simple-ui-css' => 'a8beebea',
     'phui-pager-css' => 'edcbc226',
     'phui-pinboard-view-css' => '2495140e',
-    'phui-property-list-view-css' => '94a14381',
+    'phui-property-list-view-css' => '47018d3c',
     'phui-remarkup-preview-css' => '54a34863',
     'phui-segment-bar-view-css' => 'b1d1b892',
     'phui-spacing-css' => '042804d6',

src/__phutil_library_map__.php

@@ -3519,6 +3519,7 @@ phutil_register_library_map(array(
     'PhabricatorOwnersPathsSearchEngineAttachment' => 'applications/owners/engineextension/PhabricatorOwnersPathsSearchEngineAttachment.php',
     'PhabricatorOwnersSchemaSpec' => 'applications/owners/storage/PhabricatorOwnersSchemaSpec.php',
     'PhabricatorOwnersSearchField' => 'applications/owners/searchfield/PhabricatorOwnersSearchField.php',
+    'PhabricatorPDFDocumentEngine' => 'applications/files/document/PhabricatorPDFDocumentEngine.php',
     'PhabricatorPHDConfigOptions' => 'applications/config/option/PhabricatorPHDConfigOptions.php',
     'PhabricatorPHID' => 'applications/phid/storage/PhabricatorPHID.php',
     'PhabricatorPHIDConstants' => 'applications/phid/PhabricatorPHIDConstants.php',
@@ -9169,6 +9170,7 @@ phutil_register_library_map(array(
     'PhabricatorOwnersPathsSearchEngineAttachment' => 'PhabricatorSearchEngineAttachment',
     'PhabricatorOwnersSchemaSpec' => 'PhabricatorConfigSchemaSpec',
     'PhabricatorOwnersSearchField' => 'PhabricatorSearchTokenizerField',
+    'PhabricatorPDFDocumentEngine' => 'PhabricatorDocumentEngine',
     'PhabricatorPHDConfigOptions' => 'PhabricatorApplicationConfigOptions',
     'PhabricatorPHID' => 'Phobject',
     'PhabricatorPHIDConstants' => 'Phobject',

src/aphront/response/AphrontResponse.php

@@ -28,6 +28,7 @@ abstract class AphrontResponse extends Phobject {
          'connect-src' => array(),
          'frame-src' => array(),
          'form-action' => array(),
+         'object-src' => array(),
        );
     }
 
@@ -163,8 +164,10 @@ abstract class AphrontResponse extends Phobject {
       $csp[] = "frame-ancestors 'none'";
     }
 
-    // Block relics of the old world: Flash, Java applets, and so on.
-    $csp[] = "object-src 'none'";
+    // Block relics of the old world: Flash, Java applets, and so on. Note
+    // that Chrome prevents the user from viewing PDF documents if they are
+    // served with a policy which excludes the domain they are served from.
+    $csp[] = $this->newContentSecurityPolicy('object-src', "'none'");
 
     // Don't allow forms to submit offsite.
 

src/applications/files/config/PhabricatorFilesConfigOptions.php

@@ -45,6 +45,8 @@ final class PhabricatorFilesConfigOptions
       'video/ogg' => 'video/ogg',
       'video/webm' => 'video/webm',
       'video/quicktime' => 'video/quicktime',
+
+      'application/pdf' => 'application/pdf',
     );
 
     $image_default = array(

src/applications/files/controller/PhabricatorFileDataController.php

@@ -73,11 +73,14 @@ final class PhabricatorFileDataController extends PhabricatorFileController {
       list($begin, $end) = $response->parseHTTPRange($range);
     }
 
-    $is_viewable = $file->isViewableInBrowser();
+    if (!$file->isViewableInBrowser()) {
+      $is_download = true;
+    }
+
     $request_type = $request->getHTTPHeader('X-Phabricator-Request-Type');
     $is_lfs = ($request_type == 'git-lfs');
 
-    if ($is_viewable && !$is_download) {
+    if (!$is_download) {
       $response->setMimeType($file->getViewableMimeType());
     } else {
       $is_post = $request->isHTTPPost();
@@ -109,6 +112,19 @@ final class PhabricatorFileDataController extends PhabricatorFileController {
     $response->setContentLength($file->getByteSize());
     $response->setContentIterator($iterator);
 
+    // In Chrome, we must permit this domain in "object-src" CSP when serving a
+    // PDF or the browser will refuse to render it.
+    if (!$is_download && $file->isPDF()) {
+      $request_uri = id(clone $request->getAbsoluteRequestURI())
+        ->setPath(null)
+        ->setFragment(null)
+        ->setQueryParams(array());
+
+      $response->addContentSecurityPolicyURI(
+        'object-src',
+        (string)$request_uri);
+    }
+
     return $response;
   }
 

src/applications/files/document/PhabricatorPDFDocumentEngine.php

@@ -0,0 +1,57 @@
+<?php
+
+final class PhabricatorPDFDocumentEngine
+  extends PhabricatorDocumentEngine {
+
+  const ENGINEKEY = 'pdf';
+
+  public function getViewAsLabel(PhabricatorDocumentRef $ref) {
+    return pht('View as PDF');
+  }
+
+  protected function getDocumentIconIcon(PhabricatorDocumentRef $ref) {
+    return 'fa-file-pdf-o';
+  }
+
+  protected function canRenderDocumentType(PhabricatorDocumentRef $ref) {
+    // Since we just render a link to the document anyway, we don't need to
+    // check anything fancy in config to see if the MIME type is actually
+    // viewable.
+
+    return $ref->hasAnyMimeType(
+      array(
+        'application/pdf',
+      ));
+  }
+
+  protected function newDocumentContent(PhabricatorDocumentRef $ref) {
+    $viewer = $this->getViewer();
+
+    $file = $ref->getFile();
+    if ($file) {
+      $source_uri = $file->getViewURI();
+    } else {
+      throw new PhutilMethodNotImplementedException();
+    }
+
+    $name = $ref->getName();
+    $length = $ref->getByteLength();
+
+    $link = id(new PhabricatorFileLinkView())
+      ->setViewer($viewer)
+      ->setFileName($name)
+      ->setFileViewURI($source_uri)
+      ->setFileViewable(true)
+      ->setFileSize(phutil_format_bytes($length));
+
+    $container = phutil_tag(
+      'div',
+      array(
+        'class' => 'document-engine-pdf',
+      ),
+      $link);
+
+    return $container;
+  }
+
+}

src/applications/files/storage/PhabricatorFile.php

@@ -930,6 +930,19 @@ final class PhabricatorFile extends PhabricatorFileDAO
     return idx($mime_map, $mime_type);
   }
 
+  public function isPDF() {
+    if (!$this->isViewableInBrowser()) {
+      return false;
+    }
+
+    $mime_map = array(
+      'application/pdf' => 'application/pdf',
+    );
+
+    $mime_type = $this->getMimeType();
+    return idx($mime_map, $mime_type);
+  }
+
   public function isTransformableImage() {
     // NOTE: The way the 'gd' extension works in PHP is that you can install it
     // with support for only some file types, so it might be able to handle

src/view/layout/PhabricatorFileLinkView.php

@@ -101,28 +101,41 @@ final class PhabricatorFileLinkView extends AphrontTagView {
   }
 
   protected function getTagName() {
+    if ($this->getFileDownloadURI()) {
       return 'div';
+    } else {
+      return 'a';
+    }
   }
 
   protected function getTagAttributes() {
-    $mustcapture = true;
-    $sigil = 'lightboxable';
-    $meta = $this->getMeta();
-
     $class = 'phabricator-remarkup-embed-layout-link';
     if ($this->getCustomClass()) {
       $class = $this->getCustomClass();
     }
 
-    return array(
+    $attributes = array(
       'href' => $this->getFileViewURI(),
+      'target' => '_blank',
+      'rel' => 'noreferrer',
       'class' => $class,
+    );
+
+    if ($this->getFilePHID()) {
+      $mustcapture = true;
+      $sigil = 'lightboxable';
+      $meta = $this->getMeta();
+
+      $attributes += array(
         'sigil'       => $sigil,
         'meta'        => $meta,
         'mustcapture' => $mustcapture,
       );
     }
 
+    return $attributes;
+  }
+
   protected function getTagContent() {
     require_celerity_resource('phabricator-remarkup-css');
     require_celerity_resource('phui-lightbox-css');
@@ -131,6 +144,10 @@ final class PhabricatorFileLinkView extends AphrontTagView {
       ->setIcon($this->getFileIcon())
       ->addClass('phabricator-remarkup-embed-layout-icon');
 
+    $download_link = null;
+
+    $download_uri = $this->getFileDownloadURI();
+    if ($download_uri) {
       $dl_icon = id(new PHUIIconView())
         ->setIcon('fa-download');
 
@@ -138,9 +155,10 @@ final class PhabricatorFileLinkView extends AphrontTagView {
         'a',
         array(
           'class' => 'phabricator-remarkup-embed-layout-download',
-        'href' => $this->getFileDownloadURI(),
+          'href' => $download_uri,
         ),
         pht('Download'));
+    }
 
     $info = phutil_tag(
       'span',

webroot/rsrc/css/core/remarkup.css

@@ -405,8 +405,9 @@ video.phabricator-media {
   color: {$blacktext};
   min-width: 256px;
   position: relative;
-  /*height: 22px;*/
   line-height: 20px;
+  overflow: hidden;
+  min-height: 38px;
 }
 
 .phabricator-remarkup-embed-layout-icon {
@@ -426,6 +427,9 @@ video.phabricator-media {
 .phabricator-remarkup-embed-layout-link:hover {
   border-color: {$violet};
   cursor: pointer;
+}
+
+.device-desktop .phabricator-remarkup-embed-layout-link:hover {
   text-decoration: none;
 }
 

webroot/rsrc/css/phui/phui-property-list-view.css

@@ -248,3 +248,12 @@ div.phui-property-list-stacked .phui-property-list-properties
 .document-engine-remarkup {
   margin: 20px;
 }
+
+.document-engine-pdf {
+  margin: 20px;
+  text-align: center;
+}
+
+.document-engine-pdf .phabricator-remarkup-embed-layout-link {
+  text-align: left;
+}