2 files changed, 64 insertions, 0 deletions
diff --git a/lib/gitlab/database.rb b/lib/gitlab/database.rb
index 55b8f888d53..dc2537d36aa 100644
--- a/lib/gitlab/database.rb
+++ b/lib/gitlab/database.rb
@@ -35,6 +35,20 @@ module Gitlab
       order
     end
 
+    def self.nulls_first_order(field, direction = 'ASC')
+      order = "#{field} #{direction}"
+
+      if Gitlab::Database.postgresql?
+        order << ' NULLS FIRST'
+      else
+        # `field IS NULL` will be `0` for non-NULL columns and `1` for NULL
+        # columns. In the (default) ascending order, `0` comes first.
+        order.prepend("#{field} IS NULL, ") if direction == 'DESC'
+      end
+
+      order
+    end
+
     def self.random
       Gitlab::Database.postgresql? ? "RANDOM()" : "RAND()"
     end
diff --git a/lib/gitlab/route_map.rb b/lib/gitlab/route_map.rb
new file mode 100644
index 00000000000..72d00abfcc2
--- /dev/null
+++ b/lib/gitlab/route_map.rb
@@ -0,0 +1,50 @@
+module Gitlab
+  class RouteMap
+    class FormatError < StandardError; end
+
+    def initialize(data)
+      begin
+        entries = YAML.safe_load(data)
+      rescue
+        raise FormatError, 'Route map is not valid YAML'
+      end
+
+      raise FormatError, 'Route map is not an array' unless entries.is_a?(Array)
+
+      @map = entries.map { |entry| parse_entry(entry) }
+    end
+
+    def public_path_for_source_path(path)
+      mapping = @map.find { |mapping| mapping[:source] === path }
+      return unless mapping
+
+      path.sub(mapping[:source], mapping[:public])
+    end
+
+    private
+
+    def parse_entry(entry)
+      raise FormatError, 'Route map entry is not a hash' unless entry.is_a?(Hash)
+      raise FormatError, 'Route map entry does not have a source key' unless entry.has_key?('source')
+      raise FormatError, 'Route map entry does not have a public key' unless entry.has_key?('public')
+
+      source_pattern = entry['source']
+      public_path = entry['public']
+
+      if source_pattern.start_with?('/') && source_pattern.end_with?('/')
+        source_pattern = source_pattern[1...-1].gsub('\/', '/')
+
+        begin
+          source_pattern = /\A#{source_pattern}\z/
+        rescue RegexpError => e
+          raise FormatError, "Route map entry source is not a valid regular expression: #{e}"
+        end
+      end
+
+      {
+        source: source_pattern,
+        public: public_path
+      }
+    end
+  end
+end