Add page descriptions and images

A limited number of pages have defined their own descriptions, but
otherwise we default to the Project's description (if `@project` is
set), or the old `brand_title` fallback.

The image will either be the uploaded project icon (never a generated
one), the user's uploaded icon or Gravatar, or, finally, the GitLab
logo.

1 files changed, 50 insertions, 0 deletions

diff --git a/app/helpers/page_layout_helper.rb b/app/helpers/page_layout_helper.rb
index 9bf750124b2..6b16528dde6 100644
--- a/app/helpers/page_layout_helper.rb
+++ b/app/helpers/page_layout_helper.rb
@@ -8,6 +8,56 @@ module PageLayoutHelper
     @page_title.join(" \u00b7 ")
   end
 
+  # Define or get a description for the current page
+  #
+  # description - String (default: nil)
+  #
+  # If this helper is called multiple times with an argument, only the last
+  # description will be returned when called without an argument. Descriptions
+  # have newlines replaced with spaces and all HTML tags are sanitized.
+  #
+  # Examples:
+  #
+  #   page_description # => "GitLab Community Edition"
+  #   page_description("Foo")
+  #   page_description # => "Foo"
+  #
+  #   page_description("<b>Bar</b>\nBaz")
+  #   page_description # => "Bar Baz"
+  #
+  # Returns an HTML-safe String.
+  def page_description(description = nil)
+    @page_description ||= page_description_default
+
+    if description.present?
+      @page_description = description
+    else
+      sanitize(@page_description.squish, tags: [])
+    end
+  end
+
+  # Default value for page_description when one hasn't been defined manually by
+  # a view
+  def page_description_default
+    if @project
+      @project.description
+    else
+      brand_title
+    end
+  end
+
+  def page_image
+    default = image_url('gitlab_logo.png')
+
+    if @project
+      @project.avatar_url || default
+    elsif @user
+      avatar_icon(@user)
+    else
+      default
+    end
+  end
+
   def header_title(title = nil, title_url = nil)
     if title
       @header_title     = title