RubyMethodTracer is a lightweight Ruby mixin for targeted method tracing. It wraps instance methods, measures wall-clock runtime, flags errors, and can stream results to your logger without pulling in a full APM agent. Use it to surface slow paths in production or gather quick instrumentation while debugging.

• Wrap only the methods you care about; public, protected, and private methods are supported.
• Records duration, success/error state, and timestamps with thread-safe storage.
• Configurable threshold to ignore fast calls and optional log streaming via Logger.
• Zero dependencies beyond the Ruby standard library, keeping overhead minimal.

This project has not yet been published to RubyGems.

Add it to your Gemfile directly from GitHub:

# Gemfile
gem "ruby_method_tracer", github: "Seunadex/ruby_method_tracer"

Then install:

bundle install

For local development or experimentation:

git clone https://github.com/Seunadex/ruby_method_tracer.git
cd ruby_method_tracer
bundle exec rake install

Include RubyMethodTracer in any class whose instance methods you want to observe. Register the target methods with optional settings.

class Worker
  include RubyMethodTracer
  def perform(user_id)
    expensive_call(user_id)
  end
  private
  def expensive_call(id)
    # work...
  end
end
Worker.trace_methods(:perform, threshold: 0.005, auto_output: true)
Worker.new.perform(42)

With auto_output: true, each invocation prints a colorized summary:

TRACE: Worker#perform [OK] took 6.3ms

To inspect trace results programmatically, manage the tracer yourself:

tracer = RubyMethodTracer::SimpleTracer.new(Worker, threshold: 0.002)
tracer.trace_method(:perform)
Worker.new.perform(42)
pp tracer.fetch_results
# => {
#      total_calls: 1,
#      total_time: 0.0063,
#      calls: [
#        { method_name: "Worker#perform", execution_time: 0.0063, status: :success, ... }
#      ]
#    }

class OrderProcessor
  include RubyMethodTracer
  def process_order(order)
    # ... perform work ...
  end
  trace_methods :process_order, auto_output: true
end

• threshold (Float, default 0.001): minimum duration (in seconds) to record.
• auto_output (Boolean, default false): emit a log line using Logger for each recorded call.

After checking out the repo, run bin/setup to install dependencies. Then run rake spec to execute the test suite. You can also run bin/console for an interactive prompt.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version in lib/ruby_method_tracer/version.rb, and then run bundle exec rake release.

Bug reports and pull requests are welcome on GitHub at https://github.com/Seunadex/ruby_method_tracer. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

The gem is available as open source under the terms of the MIT License. See LICENSE.txt for details.

Everyone interacting in the RubyMethodTracer project's codebases, issue trackers, chat rooms, and mailing lists is expected to follow the code of conduct.