Sort by label priority

Signed-off-by: Rémy Coutable <remy@rymai.me>

app/controllers/projects/labels_controller.rb

@@ -100,7 +100,7 @@ class Projects::LabelsController < Projects::ApplicationController
   end
 
   def label_params
-    params.require(:label).permit(:title, :description, :color)
+    params.require(:label).permit(:title, :description, :color, :priority)
   end
 
   def label

app/finders/issuable_finder.rb

@@ -224,7 +224,7 @@ class IssuableFinder
   def sort(items)
     # Ensure we always have an explicit sort order (instead of inheriting
     # multiple orders when combining ActiveRecord::Relation objects).
-    params[:sort] ? items.sort(params[:sort]) : items.reorder(id: :desc)
+    params[:sort] ? items.sort(params[:sort], label_names) : items.reorder(id: :desc)
   end
 
   def by_assignee(items)
@@ -318,7 +318,11 @@ class IssuableFinder
   end
 
   def label_names
+    if labels?
       params[:label_name].is_a?(String) ? params[:label_name].split(',') : params[:label_name]
+    else
+      []
+    end
   end
 
   def current_user_related?

app/helpers/sorting_helper.rb

@@ -14,7 +14,8 @@ module SortingHelper
       sort_value_recently_signin => sort_title_recently_signin,
       sort_value_oldest_signin => sort_title_oldest_signin,
       sort_value_downvotes => sort_title_downvotes,
-      sort_value_upvotes => sort_title_upvotes
+      sort_value_upvotes => sort_title_upvotes,
+      sort_value_priority => sort_title_priority
     }
   end
 
@@ -28,6 +29,10 @@ module SortingHelper
     }
   end
 
+  def sort_title_priority
+    'Priority'
+  end
+
   def sort_title_oldest_updated
     'Oldest updated'
   end
@@ -84,6 +89,10 @@ module SortingHelper
     'Most popular'
   end
 
+  def sort_value_priority
+    'priority'
+  end
+
   def sort_value_oldest_updated
     'updated_asc'
   end

app/models/concerns/issuable.rb

@@ -48,6 +48,12 @@ module Issuable
     scope :non_archived, -> { join_project.where(projects: { archived: false }) }
 
 
+    def self.order_priority(labels)
+      select("#{table_name}.*, (#{Label.high_priority(name, table_name, labels).to_sql}) AS highest_priority")
+        .group("#{table_name}.id")
+        .reorder(nulls_last('highest_priority', 'ASC'))
+    end
+
     delegate :name,
              :email,
              to: :author,
@@ -105,12 +111,13 @@ module Issuable
       where(t[:title].matches(pattern).or(t[:description].matches(pattern)))
     end
 
-    def sort(method)
+    def sort(method, labels = [])
       case method.to_s
       when 'milestone_due_asc' then order_milestone_due_asc
       when 'milestone_due_desc' then order_milestone_due_desc
       when 'downvotes_desc' then order_downvotes_desc
       when 'upvotes_desc' then order_upvotes_desc
+      when 'priority' then order_priority(labels)
       else
         order_by(method)
       end

app/models/label.rb

@@ -27,11 +27,28 @@ class Label < ActiveRecord::Base
             format: { with: /\A[^&\?,]+\z/ },
             uniqueness: { scope: :project_id }
 
+  before_save :nillify_priority
+
   default_scope { order(title: :asc) }
 
   scope :templates, ->  { where(template: true) }
   scope :prioritized, ->(value = true) { where(priority: value) }
 
+  def self.high_priority(name, table_name, labels)
+    unfiltered = unscoped
+      .select("MIN(labels.priority)")
+      .joins("INNER JOIN label_links ON label_links.label_id = labels.id")
+      .where("label_links.target_type = '#{name}'")
+      .where("label_links.target_id = #{table_name}.id")
+      .where("labels.project_id = #{table_name}.project_id")
+
+    if labels.empty?
+      unfiltered
+    else
+      unfiltered.where("labels.title NOT IN (?)", labels)
+    end
+  end
+
   alias_attribute :name, :title
 
   def self.reference_prefix
@@ -120,4 +137,10 @@ class Label < ActiveRecord::Base
       id
     end
   end
+
+  def nillify_priority
+    unless self.priority.present?
+      self.priority = nil
+    end
+  end
 end

app/views/projects/labels/_form.html.haml

@@ -24,6 +24,10 @@
         - suggested_colors.each do |color|
           = link_to '#', style: "background-color: #{color}", data: { color: color } do
              
+  .form-group
+    = f.label :priority, "Priority", class: 'control-label'
+    .col-sm-10
+      = f.text_field :priority, class: "form-control"
 
   .form-actions
     - if @label.persisted?

app/views/shared/_sort_dropdown.html.haml

@@ -8,6 +8,8 @@
     %b.caret
   %ul.dropdown-menu.dropdown-menu-align-right.dropdown-menu-sort
     %li
+      = link_to page_filter_path(sort: sort_value_priority) do
+        = sort_title_priority
       = link_to page_filter_path(sort: sort_value_recently_created) do
         = sort_title_recently_created
       = link_to page_filter_path(sort: sort_value_oldest_created) do

config/initializers/nulls_last.rb

+module ActiveRecord
+  class Base
+    def self.nulls_last(field, direction = 'ASC')
+      if Gitlab::Database.postgresql?
+        "#{field} #{direction} NULLS LAST"
+      else
+        if direction.upcase == 'ASC'
+          "-#{field} DESC"
+        else
+          "#{field} DESC"
+        end
+      end
+    end
+  end
+end

db/migrate/20160314094147_add_priority_to_label.rb

+class AddPriorityToLabel < ActiveRecord::Migration
+  def change
+    add_column :labels, :priority, :integer
+    add_index :labels, :priority
+  end
+end

db/schema.rb

@@ -496,8 +496,10 @@ ActiveRecord::Schema.define(version: 20160530150109) do
     t.datetime "updated_at"
     t.boolean  "template",    default: false
     t.string   "description"
+    t.integer  "priority"
   end
 
+  add_index "labels", ["priority"], name: "index_labels_on_priority", using: :btree
   add_index "labels", ["project_id"], name: "index_labels_on_project_id", using: :btree
 
   create_table "lfs_objects", force: :cascade do |t|