Friday, September 26, 2025

Redirect source location logging, filterable engine routes, and more!

Posted by Greg

Happy Friday! After three weeks of conferencing, this is Greg, bringing you the news about the latest changes in your favorite framework. It was a busy week with a lot of changes, let’s dive in.

Rails Version 8.0.3 has been released!
A new version of Rails has been released. Read the CHANGELOG for the list of changes.

Deprecate usage of custom ActiveJob serializers without public #klass methods
With this change, custom Active Job serializers must have a public #klass method, the previous behavior is deprecated.

Make engine routes filterable in bin/rails routes, improve engine formatting
This pull request adds engine route filtering and better formatting in bin/rails routes.

Make all framework log subscribers API private
Some of the the internal Rails log subscriber classes were not marked as private APIs, this pull requests corrected that.

Introduce with_debug_event_reporting to enable event reporter debug mode
This pull request changes ActiveSupport::Testing::EventReporterAssertions by adding #with_debug_event_reporting to enable event reporter debug mode in tests.

Don’t generate system tests by default
Starting with Rails 8.1, scaffolds no longer generate system tests by default. System tests should be reserved for critical user paths due to their slower execution and higher maintenance cost. To include system tests when scaffolding, use the --system-tests=true option.

Structured event subscribers
Structured events are coming to framework notifications via the use of ActiveSupport::StructuredEventSubscriber subclasses. Events may be emitted with the #emit_event or #emit_debug_event methods like this, similar to a traditional LogSubscriber:

class MyStructuredEventSubscriber < ActiveSupport::StructuredEventSubscriber
  def notification(event)
    emit_event("my.notification", data: event.payload)
  end
end

MyStructuredEventSubscriber.attach_to :namespace

Support integer shard keys
With this change, integers can be used for shared keys. Here as example of doing so:

# Now accepts symbols as shard keys.
ActiveRecord::Base.connects_to(shards: {
  1: { writing: :primary_shard_one, reading: :primary_shard_one },
  2: { writing: :primary_shard_two, reading: :primary_shard_two},
})

ActiveRecord::Base.connected_to(shard: 1) do
  # ..
end

Allow logs and notifications for open redirects
The new Rails.configuration.action_controller.action_on_open_redirect configuration controls how Rails handles open redirect vulnerabilities. When set to :raise, Rails will raise an ActionController::Redirecting::UnsafeRedirectError for redirects to external hosts, which helps prevent open redirect attacks. This configuration replaces the deprecated raise_on_open_redirects setting, providing the ability for large codebases to safely turn on the protection (after monitoring it with :log(logs a warning but allows the redirect) or :notifications(sends an Active Support notification for monitoring).

Support virtual (not persisted) generated columns on PostgreSQL 18+
This pull request adds support for virtual generated columns on PostgreSQL 18 and later. Usage example:

create_table :users do |t|
  t.string :name
  t.virtual :lower_name,  type: :string,  as: "LOWER(name)", stored: false
  t.virtual :name_length, type: :integer, as: "LENGTH(name)"
end

Add only_columns to activerecord
This pull request adds ActiveRecord::Base.only_columns. Similar in use case to ignored_columns but listing columns to consider rather than the ones to ignore.
This can be useful when working with a legacy or shared database schema, or to make safe schema change in two deploys rather than three.

Add setting for logging redirect source locations
This pull request adds action_dispatch.verbose_redirect_logs setting that logs where redirects were called from. Similar to active_record.verbose_query_logs and active_job.verbose_enqueue_logs, this adds a line in your logs that shows where a redirect was called from.
For example:

Redirected to http://localhost:3000/posts/1
↳ app/controllers/posts_controller.rb:32:in `block (2 levels) in create'

You can view the whole list of changes here. We had 36 contributors to the Rails codebase this past week!

Until next time!

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