puma-metrics

A puma plugin to export Puma's internal statistics as Prometheus metrics.

Installation

Add this line to your application's Gemfile:

gem 'puma-metrics'

And then execute:

$ bundle

Or install it yourself as:

$ gem install puma-metrics

Usage

Add following lines to your puma config.rb (see Configuration File):

# config/puma.rb
# Load the metrics plugin
plugin 'metrics'

# Bind the metric server to "url". "tcp://" is the only accepted protocol.
#
# The default is "tcp://0.0.0.0:9393".
# metrics_url 'tcp://0.0.0.0:9393'

# Instead of creating a metric server, internally poll, using the configured
# interval in seconds, for the Puma metrics and assume that the Rails app
# itself provides a `/metrics` endpoint for exporting.
# metrics_poll 15
# metrics_url 'false'

Credits

The gem is inspired by the following projects:

• https://github.com/puma/puma
• https://github.com/puma/puma-heroku

License

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