Merge branch 'fix_importers' into 'master'

Fix importers with OCC

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/1180

Using validates_uniqueness_of does not guarantee the absence of duplicate record insertions. When users click button "import all" it will create duplicating group in database and data integrity will be broken.

http://api.rubyonrails.org/classes/ActiveRecord/Validations/ClassMethods.html#method-i-validates_uniqueness_of

I use optimistic concurrency control for handling this situation.

See merge request !1647

Conflicts:
	db/schema.rb

app/controllers/import/base_controller.rb

@@ -3,19 +3,17 @@ class Import::BaseController < ApplicationController
   private
   def get_or_create_namespace
-    existing_namespace = Namespace.find_by_path_or_name(@target_namespace)
-
-    if existing_namespace
-      if existing_namespace.owner == current_user
-        namespace = existing_namespace
-      else
+    begin
+      namespace = Group.create!(name: @target_namespace, path: @target_namespace, owner: current_user)
+      namespace.add_owner(current_user)
+    rescue ActiveRecord::RecordNotUnique, ActiveRecord::RecordInvalid
+      namespace = Namespace.find_by_path_or_name(@target_namespace)
+      unless namespace.owner == current_user
         @already_been_taken = true
         return false
       end
-    else
-      namespace = Group.create(name: @target_namespace, path: @target_namespace, owner: current_user)
-      namespace.add_owner(current_user)
-      namespace
     end
+
+    namespace
   end
 end

db/migrate/20150306023106_fix_namespace_duplication.rb

+class FixNamespaceDuplication < ActiveRecord::Migration
+  def up
+    #fixes path duplication
+    select_all('SELECT MAX(id) max, COUNT(id) cnt, path FROM namespaces GROUP BY path HAVING COUNT(id) > 1').each do |nms|
+      bad_nms_ids = select_all("SELECT id FROM namespaces WHERE path = '#{nms['path']}' AND id <> #{nms['max']}").map{|x| x["id"]}
+      execute("UPDATE projects SET namespace_id = #{nms["max"]} WHERE namespace_id IN(#{bad_nms_ids.join(', ')})")
+      execute("DELETE FROM namespaces WHERE id IN(#{bad_nms_ids.join(', ')})")
+    end
+
+    #fixes name duplication
+    select_all('SELECT MAX(id) max, COUNT(id) cnt, name FROM namespaces GROUP BY name HAVING COUNT(id) > 1').each do |nms|
+      bad_nms_ids = select_all("SELECT id FROM namespaces WHERE name = '#{nms['name']}' AND id <> #{nms['max']}").map{|x| x["id"]}
+      execute("UPDATE projects SET namespace_id = #{nms["max"]} WHERE namespace_id IN(#{bad_nms_ids.join(', ')})")
+      execute("DELETE FROM namespaces WHERE id IN(#{bad_nms_ids.join(', ')})")
+    end
+  end
+
+  def down
+    # not implemented
+  end
+end

db/migrate/20150306023112_add_unique_index_to_namespace.rb

+class AddUniqueIndexToNamespace < ActiveRecord::Migration
+  def change
+    remove_index :namespaces, column: :name if index_exists?(:namespaces, :name)
+    remove_index :namespaces, column: :path if index_exists?(:namespaces, :path)
+
+    add_index :namespaces, :name, unique: true
+    add_index :namespaces, :path, unique: true
+  end
+end

db/schema.rb

@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
-ActiveRecord::Schema.define(version: 20150213121042) do
+ActiveRecord::Schema.define(version: 20150306023112) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -242,9 +242,9 @@ ActiveRecord::Schema.define(version: 20150213121042) do
   end
   add_index "namespaces", ["created_at", "id"], name: "index_namespaces_on_created_at_and_id", using: :btree
-  add_index "namespaces", ["name"], name: "index_namespaces_on_name", using: :btree
+  add_index "namespaces", ["name"], name: "index_namespaces_on_name", unique: true, using: :btree
   add_index "namespaces", ["owner_id"], name: "index_namespaces_on_owner_id", using: :btree
-  add_index "namespaces", ["path"], name: "index_namespaces_on_path", using: :btree
+  add_index "namespaces", ["path"], name: "index_namespaces_on_path", unique: true, using: :btree
   add_index "namespaces", ["type"], name: "index_namespaces_on_type", using: :btree
   create_table "notes", force: true do |t|
@@ -334,12 +334,12 @@ ActiveRecord::Schema.define(version: 20150213121042) do
     t.string   "import_url"
     t.integer  "visibility_level",       default: 0,        null: false
     t.boolean  "archived",               default: false,    null: false
-    t.string   "avatar"
     t.string   "import_status"
     t.float    "repository_size",        default: 0.0
     t.integer  "star_count",             default: 0,        null: false
     t.string   "import_type"
     t.string   "import_source"
+    t.string   "avatar"
   end
   add_index "projects", ["created_at", "id"], name: "index_projects_on_created_at_and_id", using: :btree