Displays thumbnails of attached images of the issue view (#1006).

This behaviour can be turned on/off in Settings -> Display (off by default). Thumbnail size can be configured there too.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@9933 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/attachments_controller.rb

@@ -17,7 +17,7 @@
 
 class AttachmentsController < ApplicationController
   before_filter :find_project, :except => :upload
-  before_filter :file_readable, :read_authorize, :only => [:show, :download]
+  before_filter :file_readable, :read_authorize, :only => [:show, :download, :thumbnail]
   before_filter :delete_authorize, :only => :destroy
   before_filter :authorize_global, :only => :upload
 
@@ -59,6 +59,18 @@ class AttachmentsController < ApplicationController
 
   end
 
+  def thumbnail
+    if @attachment.thumbnailable? && Setting.thumbnails_enabled? && thumbnail = @attachment.thumbnail
+      send_file thumbnail,
+        :filename => filename_for_content_disposition(@attachment.filename),
+        :type => detect_content_type(@attachment),
+        :disposition => 'inline'
+    else
+      # No thumbnail for the attachment or thumbnail could not be created
+      render :nothing => true, :status => 404
+    end
+  end
+
   def upload
     # Make sure that API users get used to set this content type
     # as it won't trigger Rails' automatic parsing of the request body for parameters

app/helpers/application_helper.rb

@@ -153,6 +153,12 @@ module ApplicationHelper
     end
   end
 
+  def thumbnail_tag(attachment)
+    link_to image_tag(url_for(:controller => 'attachments', :action => 'thumbnail', :id => attachment)),
+      {:controller => 'attachments', :action => 'show', :id => attachment, :filename => attachment.filename},
+      :title => attachment.filename
+  end
+
   def toggle_link(name, id, options={})
     onclick = "Element.toggle('#{id}'); "
     onclick << (options[:focus] ? "Form.Element.focus('#{options[:focus]}'); " : "this.blur(); ")

app/helpers/attachments_helper.rb

@@ -21,12 +21,14 @@ module AttachmentsHelper
   # Displays view/delete links to the attachments of the given object
   # Options:
   #   :author -- author names are not displayed if set to false
+  #   :thumbails -- display thumbnails if enabled in settings
   def link_to_attachments(container, options = {})
-    options.assert_valid_keys(:author)
+    options.assert_valid_keys(:author, :thumbnails)
 
     if container.attachments.any?
       options = {:deletable => container.attachments_deletable?, :author => true}.merge(options)
-      render :partial => 'attachments/links', :locals => {:attachments => container.attachments, :options => options}
+      render :partial => 'attachments/links',
+        :locals => {:attachments => container.attachments, :options => options, :thumbnails => (options[:thumbnails] && Setting.thumbnails_enabled?)}
     end
   end
 

app/models/attachment.rb

@@ -46,6 +46,9 @@ class Attachment < ActiveRecord::Base
   cattr_accessor :storage_path
   @@storage_path = Redmine::Configuration['attachments_storage_path'] || File.join(Rails.root, "files")
 
+  cattr_accessor :thumbnails_storage_path
+  @@thumbnails_storage_path = File.join(Rails.root, "tmp", "thumbnails")
+
   before_save :files_to_final_location
   after_destroy :delete_from_disk
 
@@ -150,7 +153,35 @@ class Attachment < ActiveRecord::Base
   end
 
   def image?
-    self.filename =~ /\.(bmp|gif|jpg|jpe|jpeg|png)$/i
+    !!(self.filename =~ /\.(bmp|gif|jpg|jpe|jpeg|png)$/i)
+  end
+
+  def thumbnailable?
+    image?
+  end
+
+  # Returns the full path the attachment thumbnail, or nil
+  # if the thumbnail cannot be generated.
+  def thumbnail
+    if thumbnailable? && readable?
+      size = Setting.thumbnails_size.to_i
+      size = 100 unless size > 0
+      target = File.join(self.class.thumbnails_storage_path, "#{id}_#{digest}_#{size}.thumb")
+
+      begin
+        Redmine::Thumbnail.generate(self.diskfile, target, size)
+      rescue => e
+        logger.error "An error occured while generating thumbnail for #{disk_filename} to #{target}\nException was: #{e.message}" if logger
+        return nil
+      end
+    end
+  end
+
+  # Deletes all thumbnails
+  def self.clear_thumbnails
+    Dir.glob(File.join(thumbnails_storage_path, "*.thumb")).each do |file|
+      File.delete file
+    end
   end
 
   def is_text?

app/views/attachments/_links.html.erb

@@ -20,4 +20,14 @@
   <% end %>
   </p>
 <% end %>
+<% if defined?(thumbnails) && thumbnails %>
+  <% images = attachments.select(&:thumbnailable?) %>
+  <% if images.any? %>
+  <div class="thumbnails">
+    <% images.each do |attachment| %>
+      <div><%= thumbnail_tag(attachment) %></div>
+    <% end %>
+  </div>
+  <% end %>
+<% end %>
 </div>

app/views/issues/show.html.erb

@@ -81,7 +81,7 @@ end %>
   <%= textilizable @issue, :description, :attachments => @issue.attachments %>
   </div>
 <% end %>
-<%= link_to_attachments @issue %>
+<%= link_to_attachments @issue, :thumbnails => true %>
 <% end -%>
 
 <%= call_hook(:view_issues_show_description_bottom, :issue => @issue) %>

app/views/settings/_display.html.erb

@@ -16,6 +16,10 @@
 <p><%= setting_check_box :gravatar_enabled %></p>
 
 <p><%= setting_select :gravatar_default, [["Wavatars", 'wavatar'], ["Identicons", 'identicon'], ["Monster ids", 'monsterid'], ["Retro", 'retro'], ["Mystery man", 'mm']], :blank => :label_none %></p>
+
+<p><%= setting_check_box :thumbnails_enabled %></p>
+
+<p><%= setting_text_field :thumbnails_size, :size => 6 %></p>
 </div>
 
 <%= submit_tag l(:button_save) %>