Force hashed storage to always be enabled

This is part of our deprecation of Legacy Storage. In 13.0 we are
disallowing users to disable hashed storage.

app/models/application_setting.rb

@@ -266,6 +266,8 @@ class ApplicationSetting < ApplicationRecord
 
   validates :email_restrictions, untrusted_regexp: true
 
+  validates :hashed_storage_enabled, inclusion: { in: [true], message: _("Hashed storage can't be disabled anymore for new projects") }
+
   SUPPORTED_KEY_TYPES.each do |type|
     validates :"#{type}_key_restriction", presence: true, key_restriction: { type: type }
   end

app/views/admin/application_settings/_repository_storage.html.haml

@@ -6,10 +6,10 @@
       %h4= _("Hashed repository storage paths")
       .form-group
         .form-check
-          = f.check_box :hashed_storage_enabled, class: 'form-check-input qa-hashed-storage-checkbox'
+          = f.check_box :hashed_storage_enabled, class: 'form-check-input qa-hashed-storage-checkbox', disabled: @application_setting.hashed_storage_enabled?
           = f.label :hashed_storage_enabled, _("Use hashed storage"), class: 'label-bold form-check-label'
           .form-text.text-muted
-            = _("Use hashed storage paths for newly created and renamed repositories. Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Repository URL changes and may improve disk I/O performance.")
+            = _("Use hashed storage paths for newly created and renamed repositories. Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Repository URL changes and may improve disk I/O performance. (Always enabled since 13.0)")
     .sub-section
       %h4= _("Storage nodes for new repositories")
       .form-group

changelogs/unreleased/210018-remove-admin-ability-not-to-use-hashed-storage.yml

+---
+title: Force hashed storage to always be enabled
+merge_request: 31801
+author:
+type: changed

db/post_migrate/20200513171959_enable_hashed_storage.rb

+# frozen_string_literal: true
+
+class EnableHashedStorage < ActiveRecord::Migration[6.0]
+  DOWNTIME = false
+
+  class ApplicationSetting < ActiveRecord::Base
+    self.table_name = 'application_settings'
+  end
+
+  def up
+    ApplicationSetting.update_all(hashed_storage_enabled: true)
+  end
+
+  def down
+    # in 13.0 we are forcing hashed storage to always be enabled for new projects
+  end
+end

db/structure.sql

@@ -13820,6 +13820,7 @@ COPY "schema_migrations" (version) FROM STDIN;
 20200512085150
 20200512164334
 20200513160930
+20200513171959
 20200513234502
 20200513235347
 20200513235532

doc/api/settings.md

@@ -262,7 +262,7 @@ are listed in the descriptions of the relevant settings.
 | `grafana_enabled`                        | boolean          | no                                   | Enable Grafana. |
 | `grafana_url`                            | string           | no                                   | Grafana URL. |
 | `gravatar_enabled`                       | boolean          | no                                   | Enable Gravatar. |
-| `hashed_storage_enabled`                 | boolean          | no                                   | Create new projects using hashed storage paths: Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Project URL changes and may improve disk I/O performance. (EXPERIMENTAL) |
+| `hashed_storage_enabled`                 | boolean          | no                                   | Create new projects using hashed storage paths: Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Project URL changes and may improve disk I/O performance. (Always enabled since 13.0, configuration will be removed in 14.0) |
 | `help_page_hide_commercial_content`      | boolean          | no                                   | Hide marketing-related entries from help. |
 | `help_page_support_url`                  | string           | no                                   | Alternate support URL for help page and help dropdown. |
 | `help_page_text`                         | string           | no                                   | Custom text displayed on the help page. |

lib/api/settings.rb

@@ -185,6 +185,9 @@ module API
         attrs[:allow_local_requests_from_web_hooks_and_services] = attrs.delete(:allow_local_requests_from_hooks_and_services)
       end
 
+      # since 13.0 it's not possible to disable hashed storage - support can be removed in 14.0
+      attrs.delete(:hashed_storage_enabled) if attrs.has_key?(:hashed_storage_enabled)
+
       attrs = filter_attributes_using_license(attrs)
 
       if ApplicationSettings::UpdateService.new(current_settings, current_user, attrs).execute

locale/gitlab.pot

@@ -11033,6 +11033,9 @@ msgstr ""
 msgid "Hashed repository storage paths"
 msgstr ""
 
+msgid "Hashed storage can't be disabled anymore for new projects"
+msgstr ""
+
 msgid "Have your users email"
 msgstr ""
 
@@ -23262,7 +23265,7 @@ msgstr ""
 msgid "Use hashed storage"
 msgstr ""
 
-msgid "Use hashed storage paths for newly created and renamed repositories. Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Repository URL changes and may improve disk I/O performance."
+msgid "Use hashed storage paths for newly created and renamed repositories. Enable immutable, hash-based paths and repository names to store repositories on disk. This prevents repositories from having to be moved or renamed when the Repository URL changes and may improve disk I/O performance. (Always enabled since 13.0)"
 msgstr ""
 
 msgid "Use one line per URI"

spec/models/application_setting_spec.rb

@@ -103,6 +103,8 @@ describe ApplicationSetting do
     it { is_expected.not_to allow_value(10.5).for(:raw_blob_request_limit) }
     it { is_expected.not_to allow_value(-1).for(:raw_blob_request_limit) }
 
+    it { is_expected.not_to allow_value(false).for(:hashed_storage_enabled) }
+
     context 'grafana_url validations' do
       before do
         subject.instance_variable_set(:@parsed_grafana_url, nil)

spec/requests/api/settings_spec.rb

@@ -159,6 +159,14 @@ describe API::Settings, 'Settings' do
       expect(json_response['allow_local_requests_from_hooks_and_services']).to eq(true)
     end
 
+    it 'disables ability to switch to legacy storage' do
+      put api("/application/settings", admin),
+          params: { hashed_storage_enabled: false }
+
+      expect(response).to have_gitlab_http_status(:ok)
+      expect(json_response['hashed_storage_enabled']).to eq(true)
+    end
+
     context 'external policy classification settings' do
       let(:settings) do
         {