Update to Rails 6.0.0

config/environments/development.rb

@@ -16,6 +16,7 @@ Rails.application.configure do
   # Run rails dev:cache to toggle caching.
   if Rails.root.join('tmp', 'caching-dev.txt').exist?
     config.action_controller.perform_caching = true
+    config.action_controller.enable_fragment_cache_logging = true
 
     config.cache_store = :memory_store
     config.public_file_server.headers = {
@@ -27,7 +28,7 @@ Rails.application.configure do
     config.cache_store = :null_store
   end
 
-  # Store uploaded files on the local file system (see config/storage.yml for options)
+  # Store uploaded files on the local file system (see config/storage.yml for options).
   config.active_storage.service = :local
 
   # Don't care if the mailer can't send.
@@ -52,7 +53,7 @@ Rails.application.configure do
   # Suppress logger output for asset requests.
   config.assets.quiet = true
 
-  # Raises error for missing translations
+  # Raises error for missing translations.
   config.action_view.raise_on_missing_translations = true
 
   # Use an evented file watcher to asynchronously detect changes in source code,

config/environments/production.rb

@@ -22,15 +22,15 @@ Rails.application.configure do
   # Apache or NGINX already handles this.
   config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].present?
 
-  # Compress JavaScripts and CSS.
+  # Compress JS using a preprocessor.
   config.assets.js_compressor = :uglifier
+  
+  # Compress CSS using a preprocessor.
   # config.assets.css_compressor = :sass
 
   # Do not fallback to assets pipeline if a precompiled asset is missed.
   config.assets.compile = false
 
-  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
-
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
   # config.action_controller.asset_host = 'http://assets.example.com'
 
@@ -38,10 +38,10 @@ Rails.application.configure do
   # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
   # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
 
-  # Store uploaded files on the local file system (see config/storage.yml for options)
+  # Store uploaded files on the local file system (see config/storage.yml for options).
   config.active_storage.service = :local
 
-  # Mount Action Cable outside main process or domain
+  # Mount Action Cable outside main process or domain.
   # config.action_cable.mount_path = nil
   # config.action_cable.url = 'wss://example.com/cable'
   # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
@@ -59,9 +59,9 @@ Rails.application.configure do
   # Use a different cache store in production.
   # config.cache_store = :mem_cache_store
 
-  # Use a real queuing backend for Active Job (and separate queues per environment)
+  # Use a real queuing backend for Active Job (and separate queues per environment).
   # config.active_job.queue_adapter     = :resque
-  # config.active_job.queue_name_prefix = "projekteuler_#{Rails.env}"
+  # config.active_job.queue_name_prefix = "projekteuler_production"
 
   config.action_mailer.perform_caching = false
 
@@ -91,4 +91,25 @@ Rails.application.configure do
 
   # Do not dump schema after migrations.
   config.active_record.dump_schema_after_migration = false
+
+  # Inserts middleware to perform automatic connection switching.
+  # The `database_selector` hash is used to pass options to the DatabaseSelector
+  # middleware. The `delay` is used to determine how long to wait after a write
+  # to send a subsequent read to the primary.
+  #
+  # The `database_resolver` class is used by the middleware to determine which
+  # database is appropriate to use based on the time delay.
+  #
+  # The `database_resolver_context` class is used by the middleware to set
+  # timestamps for the last write to the primary. The resolver uses the context
+  # class timestamps to determine how long to wait before reading from the
+  # replica.
+  #
+  # By default Rails will store a last write timestamp in the session. The
+  # DatabaseSelector middleware is designed as such you can define your own
+  # strategy for connection switching and pass that into the middleware through
+  # these configuration options.
+  # config.active_record.database_selector = { delay: 2.seconds }
+  # config.active_record.database_resolver = ActiveRecord::Middleware::DatabaseSelector::Resolver
+  # config.active_record.database_resolver_context = ActiveRecord::Middleware::DatabaseSelector::Resolver::Session
 end

config/environments/test.rb

@@ -1,10 +1,11 @@
+# The test environment is used exclusively to run your application's
+# test suite. You never need to work with it otherwise. Remember that
+# your test database is "scratch space" for the test suite and is wiped
+# and recreated between test runs. Don't rely on the data there!
+
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
-
-  # The test environment is used exclusively to run your application's
-  # test suite. You never need to work with it otherwise. Remember that
-  # your test database is "scratch space" for the test suite and is wiped
-  # and recreated between test runs. Don't rely on the data there!
+  
   config.cache_classes = true
 
   # Do not eager load code on boot. This avoids loading your whole application
@@ -21,6 +22,7 @@ Rails.application.configure do
   # Show full error reports and disable caching.
   config.consider_all_requests_local       = true
   config.action_controller.perform_caching = false
+  config.cache_store = :null_store
 
   # Raise exceptions instead of rendering exception templates.
   config.action_dispatch.show_exceptions = false
@@ -28,7 +30,7 @@ Rails.application.configure do
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false
 
-  # Store uploaded files on the local file system in a temporary directory
+  # Store uploaded files on the local file system in a temporary directory.
   config.active_storage.service = :test
 
   config.action_mailer.perform_caching = false
@@ -41,6 +43,6 @@ Rails.application.configure do
   # Print deprecation notices to the stderr.
   config.active_support.deprecation = :stderr
 
-  # Raises error for missing translations
+  # Raises error for missing translations.
   config.action_view.raise_on_missing_translations = true
 end