Put FASP support behind a feature flag

app/models/account.rb

@@ -85,7 +85,7 @@ class Account < ApplicationRecord
   include Account::Associations
   include Account::Avatar
   include Account::Counters
-  include Account::FaspConcern
+  include Account::FaspConcern if Mastodon::Feature.fasp_enabled?
   include Account::FinderConcern
   include Account::Header
   include Account::Interactions

app/models/favourite.rb

@@ -13,7 +13,7 @@
 
 class Favourite < ApplicationRecord
   include Paginable
-  include Favourite::FaspConcern
+  include Favourite::FaspConcern if Mastodon::Feature.fasp_enabled?
 
   update_index('statuses', :status)
 

app/models/status.rb

@@ -34,7 +34,7 @@ class Status < ApplicationRecord
   include Discard::Model
   include Paginable
   include RateLimitable
-  include Status::FaspConcern
+  include Status::FaspConcern if Mastodon::Feature.fasp_enabled?
   include Status::SafeReblogInsert
   include Status::SearchConcern
   include Status::SnapshotConcern

config/application.rb

@@ -34,6 +34,7 @@ require_relative '../lib/paperclip/transcoder'
 require_relative '../lib/paperclip/type_corrector'
 require_relative '../lib/paperclip/response_with_limit_adapter'
 require_relative '../lib/terrapin/multi_pipe_extensions'
+require_relative '../lib/mastodon/feature'
 require_relative '../lib/mastodon/snowflake'
 require_relative '../lib/mastodon/version'
 require_relative '../lib/mastodon/rack_middleware'

config/navigation.rb

@@ -73,7 +73,7 @@ SimpleNavigation::Configuration.run do |navigation|
       s.item :announcements, safe_join([material_symbol('campaign'), t('admin.announcements.title')]), admin_announcements_path, highlights_on: %r{/admin/announcements}, if: -> { current_user.can?(:manage_announcements) }
       s.item :custom_emojis, safe_join([material_symbol('mood'), t('admin.custom_emojis.title')]), admin_custom_emojis_path, highlights_on: %r{/admin/custom_emojis}, if: -> { current_user.can?(:manage_custom_emojis) }
       s.item :webhooks, safe_join([material_symbol('inbox'), t('admin.webhooks.title')]), admin_webhooks_path, highlights_on: %r{/admin/webhooks}, if: -> { current_user.can?(:manage_webhooks) }
-      s.item :fasp, safe_join([material_symbol('extension'), t('admin.fasp.title')]), admin_fasp_providers_path, highlights_on: %r{/admin/fasp}, if: -> { current_user.can?(:manage_federation) }
+      s.item :fasp, safe_join([material_symbol('extension'), t('admin.fasp.title')]), admin_fasp_providers_path, highlights_on: %r{/admin/fasp}, if: -> { current_user.can?(:manage_federation) } if Mastodon::Feature.fasp_enabled?
       s.item :relays, safe_join([material_symbol('captive_portal'), t('admin.relays.title')]), admin_relays_path, highlights_on: %r{/admin/relays}, if: -> { !limited_federation_mode? && current_user.can?(:manage_federation) }
     end
 

config/routes.rb

@@ -196,7 +196,7 @@ Rails.application.routes.draw do
 
   draw(:api)
 
-  draw(:fasp)
+  draw(:fasp) if Mastodon::Feature.fasp_enabled?
 
   draw(:web_app)
 

lib/mastodon/feature.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Mastodon
+  module Feature
+    FASP_ENABLED = ENV['EXPERIMENTAL_FASP'] == 'true'
+
+    def self.fasp_enabled?
+      FASP_ENABLED
+    end
+  end
+end