Render PDF thumbnail using ImageMagick/GhostScript (#22481).

Patch by Gregor Schmidt.


git-svn-id: http://svn.redmine.org/redmine/trunk@18158 e93f8b46-1217-0410-a6f0-8f06a7374b81

3 files changed, 16 insertions, 7 deletions

diff --git a/app/controllers/admin_controller.rb b/app/controllers/admin_controller.rb
index 91d3b0712..eb2288eff 100644
--- a/app/controllers/admin_controller.rb
+++ b/app/controllers/admin_controller.rb
@@ -77,7 +77,8 @@ class AdminController < ApplicationController
       [:text_file_repository_writable, File.writable?(Attachment.storage_path)],
       ["#{l :text_plugin_assets_writable} (./public/plugin_assets)",   File.writable?(Redmine::Plugin.public_directory)],
       [:text_rmagick_available,        Object.const_defined?(:Magick)],
-      [:text_convert_available,        Redmine::Thumbnail.convert_available?]
+      [:text_convert_available,        Redmine::Thumbnail.convert_available?],
+      [:text_gs_available,             Redmine::Thumbnail.gs_available?]
     ]
   end
 end
diff --git a/app/controllers/attachments_controller.rb b/app/controllers/attachments_controller.rb
index bc558fdc0..4817149a4 100644
--- a/app/controllers/attachments_controller.rb
+++ b/app/controllers/attachments_controller.rb
@@ -83,7 +83,7 @@ class AttachmentsController < ApplicationController
       if stale?(:etag => tbnail)
         send_file tbnail,
           :filename => filename_for_content_disposition(@attachment.filename),
-          :type => detect_content_type(@attachment),
+          :type => detect_content_type(@attachment, true),
           :disposition => 'inline'
       end
     else
@@ -236,12 +236,20 @@ class AttachmentsController < ApplicationController
     @attachment.deletable? ? true : deny_access
   end
 
-  def detect_content_type(attachment)
+  def detect_content_type(attachment, is_thumb = false)
     content_type = attachment.content_type
     if content_type.blank? || content_type == "application/octet-stream"
-      content_type = Redmine::MimeType.of(attachment.filename)
+      content_type = 
+        Redmine::MimeType.of(attachment.filename).presence ||
+        "application/octet-stream"
     end
-    content_type.presence || "application/octet-stream"
+
+    if is_thumb && content_type == "application/pdf"
+      # PDF previews are stored in PNG format
+      content_type = "image/png"
+    end
+
+    content_type
   end
 
   def disposition(attachment)
diff --git a/app/models/attachment.rb b/app/models/attachment.rb
index 362ac1fde..a0d712a34 100644
--- a/app/models/attachment.rb
+++ b/app/models/attachment.rb
@@ -201,7 +201,7 @@ class Attachment < ActiveRecord::Base
   end
 
   def thumbnailable?
-    image?
+    image? || (is_pdf? && Redmine::Thumbnail.gs_available?)
   end
 
   # Returns the full path the attachment thumbnail, or nil
@@ -221,7 +221,7 @@ class Attachment < ActiveRecord::Base
       target = thumbnail_path(size)
 
       begin
-        Redmine::Thumbnail.generate(self.diskfile, target, size)
+        Redmine::Thumbnail.generate(self.diskfile, target, size, is_pdf?)
       rescue => e
         logger.error "An error occured while generating thumbnail for #{disk_filename} to #{target}\nException was: #{e.message}" if logger
         return nil