Upgrade to Rails 6.0 and apply new framework defaults

config/initializers/action_mailer.rb

@@ -1,3 +1,7 @@
+# frozen_string_literal: true
+
+require 'code_ocean/config'
+
 CodeOcean::Config.new(:action_mailer).read.each do |key, value|
   CodeOcean::Application.config.action_mailer.send(:"#{key}=", value.respond_to?(:symbolize_keys) ? value.symbolize_keys : value)
 end

config/initializers/assets.rb

@@ -1,20 +1,19 @@
+# frozen_string_literal: true
+
 # Be sure to restart your server when you modify this file.
 
-Rails.application.config.tap do |config|
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = '1.0'
 
-  # Version of your assets, change this if you want to expire all your assets.
-  config.assets.version = '1.0'
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+# Add Yarn node_modules folder to the asset load path.
+Rails.application.config.assets.paths << Rails.root.join('node_modules')
 
-  # Add additional assets to the asset load path.
-  # config.assets.paths << Emoji.images_path
-  # Add Yarn node_modules folder to the asset load path.
-  config.assets.paths << Rails.root.join('node_modules')
-
-  # Precompile additional assets.
-  # application.js, application.css, and all non-JS/CSS in the app/assets
-  # folder are already added.
-  # config.assets.precompile += %w( admin.js admin.css )
-end
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+Rails.application.config.assets.precompile += %w( markdown-buttons.png )
 
 # Disable concurrent asset compilation to prevent segfault # https://github.com/sass/sassc-ruby/issues/197
 # Reproduce: `rake assets:clobber`, `rake assets:precompile`. If the command succeeds, it worked

config/initializers/content_security_policy.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Be sure to restart your server when you modify this file.
 
 # Define an application-wide content security policy
@@ -11,10 +13,7 @@
 #   policy.object_src  :none
 #   policy.script_src  :self, :https
 #   policy.style_src   :self, :https
-#
-#   # You need to allow webpack-dev-server host as allowed origin for connect-src.
-#   # This can be done in Rails 5.2+ for development environment in the CSP initializer
-#   # config/initializers/content_security_policy.rb with a snippet like this:
+#   # If you are using webpack-dev-server then specify webpack-dev-server host
 #   policy.connect_src :self, :https, "http://localhost:3035", "ws://localhost:3035" if Rails.env.development?
 
 #   # Specify URI for violation reports
@@ -24,6 +23,9 @@
 # If you are using UJS then enable automatic nonce generation
 # Rails.application.config.content_security_policy_nonce_generator = -> request { SecureRandom.base64(16) }
 
+# Set the nonce only to specific directives
+# Rails.application.config.content_security_policy_nonce_directives = %w(script-src)
+
 # Report CSP violations to a specified URI
 # For further information see the following documentation:
 # https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy-Report-Only

config/initializers/docker.rb

@@ -1,8 +1,5 @@
+# frozen_string_literal: true
+
+require 'docker_client'
+
 DockerClient.initialize_environment unless Rails.env.test? && `which docker`.blank?
-
-return if Rake.application.top_level_tasks.to_s.include?('db:')
-
-if ApplicationRecord.connection.tables.present? &&
-    DockerContainerPool.config[:active]
-  # no op
-end

config/initializers/mixins.rb

@@ -1 +1,5 @@
-Docker::Container.send(:include, DockerContainerMixin)
+# frozen_string_literal: true
+
+require 'docker_container_mixin'
+
+Docker::Container.include DockerContainerMixin

config/initializers/prometheus.rb

@@ -1,9 +1,13 @@
 # frozen_string_literal: true
 
+require 'code_ocean/config'
+
 return unless CodeOcean::Config.new(:code_ocean).read[:prometheus_exporter][:enabled] && !defined?(::Rails::Console)
 return if %w[db: assets:].any? { |task| Rake.application.top_level_tasks.to_s.include?(task) }
 
 # Add metric callbacks to all models
-ApplicationRecord.include Prometheus::Record
+ActiveSupport.on_load :active_record do
+  include Prometheus::Record
+end
 
 # Initialization is performed in config/application.rb

config/initializers/rails_admin.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 RailsAdmin.config do |config|
 
   ### Popular gems integration