lwf / riemann-ruby-client

A Ruby client for the Riemann event system

Installing

gem install riemann-client

Use

require 'riemann/client'

# Create a client. Host, port and timeout are optional.
c = Riemann::Client.new host: 'localhost', port: 5555, timeout: 5

# Send a simple event
c << {service: 'testing', metric: 2.5}

# Or a more complex one
c << {
  host: 'web3',
  service: 'api latency',
  state: 'warn',
  metric: 63.5,
  description: "63.5 milliseconds per request",
  time: Time.now.to_i - 10
}

# :host defaults to gethostname(). :time defaults to current unix time. You
# can explicitly override host...

c << {host: nil, service: 'the cloud', state: 'nebulous'}

# Get all the states from the server
c['true']

# Or specific states matching a query
c['host =~ "%.dc1" and (state = "critical" or state = "warning")']

Transports

Riemann::Client sends small events over UDP by default, and uses TCP for queries and large events. UDP sends are essentially "shouting into the void". They will not block your application and are roughly an order of magnitude faster than TCP, but you will not know if the server is down or encountered an error. You can specify what transport to use by selecting a subclient:

c.udp << { :state "ok" } # => nil
c.tcp << { :state "ok" } # => #<Message ...>
c.tcp["true"]            # => [#<Event ... >, ...]
c.udp["true"]            # => raise Riemann::Client::Unsupported

Client state management

Riemann::Client provides some classes to make managing state updates easier.

Riemann::MetricThread starts a thread to poll a metric periodically, which can be used to flush an accumulated value to ustate at regular intervals.

Riemann::AutoState bundles a state and a client together. Any changes to the AutoState automatically send the new state to the client.