grape_rails_logger

Rails-compatible structured logging for Grape APIs with ActiveRecord timing, parameter filtering, and exception tracking.

Sponsored by Kisko Labs.

Add to your Gemfile:

gem "grape_rails_logger"

Run bundle install or gem install grape_rails_logger.

The gem works automatically in Rails applications. No configuration needed. It automatically patches Grape::Endpoint#build_stack to instrument requests and subscribes to grape.request notifications, logging structured data via Rails.logger. Works with any Rails logger or integrates with activesupport-json_logging for JSON output.

Each request logs structured data with:

• Request metadata: method, path, status, duration, host, remote_addr, request_id
• Route information: controller, action, source_location (file:line)
• Performance metrics: duration (ms), db (ActiveRecord query time in ms), db_calls (SQL query count)
• Parameters: params (automatically filtered using Rails filter_parameters)
• Exceptions: exception object with class, message, and backtrace (non-production only)

Configure parameter filtering in config/initializers/filter_parameter_logging.rb:

Rails.application.config.filter_parameters += [
  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
]

When Rails ParameterFilter is not available, the gem falls back to manual filtering that detects sensitive patterns (password, secret, token, key) in parameter keys.

Optional DebugTracer middleware provides detailed request tracing when the debug gem is installed and TRACE environment variable is set:

class API < Grape::API
  use GrapeRailsLogger::DebugTracer
end

Enable tracing: TRACE=1 rails server. The middleware gracefully degrades if the debug gem is not installed.

• Rails 6.0, 6.1, 7.0, 7.1, 7.2, 8.0+
• Grape >= 1.6
• Ruby >= 2.7

In Rails 7.1+, the gem uses ActiveSupport::IsolatedExecutionState for improved thread/Fiber safety. In Rails 6-7.0, it falls back to Thread.current.

bundle install
bundle exec appraisal generate
bundle exec rspec
bin/appraisals
bundle exec standardrb --fix

Bug reports and pull requests are welcome on GitHub at https://github.com/amkisko/grape_rails_logger.rb

Contribution policy:

• New features are not necessarily added to the gem
• Pull request should have test coverage for affected parts
• Pull request should have changelog entry

Review policy:

• It might take up to 2 calendar weeks to review and merge critical fixes
• It might take up to 6 calendar months to review and merge pull request
• It might take up to 1 calendar year to review an issue

rm grape_rails_logger-*.gem
gem build grape_rails_logger.gemspec
gem push grape_rails_logger-*.gem

Or use the release script:

usr/bin/release.rb

The gem is available as open source under the terms of the MIT License.