PostgresMonitor

This gem is designed to expose a number of internal metrics and statistics for Postgres installations to the calling application. It borrows heavily from Heroku's PG Extras and Boundless's plugin for New Relic-- source.

In each case there were drawbacks that led me to create this gem. Heroku PG Extra's only works on Heroku installations. The New Relic plugin only accepts numerical values; I wanted to see the actual queries in some cases.

It uses the PG gem for its connections to Postgres

Add this line to your application's Gemfile:

gem 'postgres_monitor'

And then execute:

$ bundle

Or install it yourself as:

$ gem install postgres_monitor

To create a connection you will need to supply the host name, user, password (can be nil), and dbname. Port will default to 5432 if it is not provided. sslmode will default to required if it is not supplied.

Additionally there is a variable for configuring the long running query threshold. It defaults to '5 seconds' and follows the Postgres format for time intervals (e.g. '1 minute', '20 seconds')

@connection_params = {
  host: 'localhost',
  port: nil, # defaults to 5432
  user: 'postgres',
  password: 'password',
  sslmode: 'allow',
  dbname: 'postrges'
  long_query_threshold: '1 second'
}

@monitor = PostgresMonitor::Monitor.new(@connection_params)

The methods return the raw PG::Result for interpretation. This is a collection of hashes, well sometimes just one hash, with the results and keys in them.

results = @monitor.list_databases
databases = []
results.each do |row|
  databases << row['datname']
end

After checking out the repo, run bin/setup to install dependencies. Then, run rake rspec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

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

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