Logging errors due to the ActiveRecord log subscriber handling Rails 8 as an older Rails version

[rubyroobs]

(If you are trying to create a new project with or upgrade to Rails 8 and having this issue, I have a temporary workaround at the bottom!)

Environment

ruby 3.3.6
rails_semantic_logger 4.17.0
rails 8.0.0

Expected Behavior

sql.active_record events should be logged properly.

Actual Behavior

Some combinations of binds in the query lead to logging errors like this:

2024-11-14 12:24:35.453837 E [39239:5920 log_subscriber.rb:188] ActiveRecord -- Could not log "sql.active_record" event. NoMethodError: undefined method `type' for an instance of Integer ["/Users/ruby/.asdf/installs/ruby/3.3.6/lib/ruby/gems/3.3.0/gems/rails_semantic_logger-4.17.0/lib/rails_semantic_logger/active_record/log_subscriber.rb:162:in `render_bind_v5_0_3'"

We can see from the stack trace it's calling render_bind_v5_0_3 in RailsSemanticLogger::ActiveRecord::LogSubscriber, and from looking at the source code there we can see this is due to the logic used to setup event handlers by Rails version defaulting to treating it as Rails 5/5.1/6:

# ...
elsif (Rails::VERSION::MAJOR == 6 && Rails::VERSION::MINOR > 0) || # ~> 6.1.0
       Rails::VERSION::MAJOR == 7
  alias bind_values bind_values_v6_1
  alias render_bind render_bind_v6_1
  alias type_casted_binds type_casted_binds_v5_1_5
elsif Rails::VERSION::MAJOR >= 5 # ~> 5.1.5 && ~> 5.0.7 && 6.x.x
  alias bind_values bind_values_v5_1_5
  alias render_bind render_bind_v5_0_3
  alias type_casted_binds type_casted_binds_v5_1_5
# ...

Proposed permanent fix

To stop this from happening when the Rails major version increases again (assuming there's no other incompatibility), the check for Rails 7 should probably be changed to >= from == in RailsSemanticLogger::ActiveRecord::LogSubscriber.

# ...
elsif (Rails::VERSION::MAJOR == 6 && Rails::VERSION::MINOR > 0) || # ~> 6.1.0 && 7.x.x && 8.x.x
       Rails::VERSION::MAJOR >= 7
# ...

I haven't looked at any of the other subscriber classes other than ActiveRecord, so there likely needs to be updates made there too.

Temporary fix (for those creating a new project with/upgrading to Rails 8)

As a temporary workaround until the gem is actually properly tested with Rails 8 and a new version is released, here's a monkeypatch that got things working for me on Rails 8.0.0 and version 4.17.0 of this gem. To use it, make a new file in your initializers folder (i.e. config/initializers/rails_semantic_logger_8_monkeypatch.rb) with the following contents:

# frozen_string_literal: true

LAST_TESTED_VERSION = "4.17.0"

require "rails_semantic_logger/version"

unless RailsSemanticLogger::VERSION == LAST_TESTED_VERSION
  raise "rails_semantic_logger is version #{RailsSemanticLogger::VERSION} but the monkey patch was last tested on #{LAST_TESTED_VERSION} - manually check if it supports Rails 8 now and this can be removed, or that this still works as intended"
end

module LogSubscriberMonkeyPatch
  def self.included(base)
    base.alias_method(:bind_values, :bind_values_v6_1)
    base.alias_method(:render_bind, :render_bind_v6_1)
    base.alias_method(:type_casted_binds, :type_casted_binds_v5_1_5)
  end
end

RailsSemanticLogger::ActiveRecord::LogSubscriber.include(LogSubscriberMonkeyPatch)

This also will check when your Rails application starts that you are still using 4.17.0 and will raise if the gem version does not match. My project is using Renovatebot so this is helpful to ensure CI will fail when it creates the change to upgrade to a newer version of this gem, but it's not necessary to just get things working in Rails 8.

[DylanFM]

Just a short note to say that I have encountered this bug and came to the same conclusion about the cause. Pleased to find such a thorough issue already reported. Nice work, thanks @rubyroobs!