Class: Rack::InfluxDB

Inherits:
Object
  • Object
show all
Defined in:
lib/rack/influxdb.rb,
lib/rack/influxdb/version.rb,
lib/rack/influxdb/configuration.rb

Overview

The InfluxDB rack middleware class.

Defined Under Namespace

Classes: Configuration

Constant Summary collapse

DEFAULT_QUEUE_SIZE =

Caps how many computed points can be buffered while waiting to be written. If InfluxDB becomes slow or unreachable, the queue fills up and further points are dropped (see #enqueue) instead of growing without bound or blocking requests.

1_000
VERSION = 
'0.2.0'

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ InfluxDB

Returns a new instance of InfluxDB.



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# File 'lib/rack/influxdb.rb', line 25

def initialize(app)
  @app = app
  @queue = SizedQueue.new(DEFAULT_QUEUE_SIZE)
  @worker_mutex = Mutex.new
  @worker = nil

  # Flush whatever is left in the queue when the process exits (e.g. on
  # a graceful Puma shutdown), so the last few requests before shutdown
  # aren't silently lost. This never blocks a request, only exit.
  at_exit { shutdown }
end

Class Method Details

.configuration ⇒ Object 



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# File 'lib/rack/influxdb.rb', line 16

def configuration
  @configuration ||= Rack::InfluxDB::Configuration.new
end

.configure {|configuration| ... } ⇒ Object

Yields:



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# File 'lib/rack/influxdb.rb', line 20

def configure
  yield(configuration)
end

Instance Method Details

#call(env) ⇒ Object 



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# File 'lib/rack/influxdb.rb', line 37

def call(env)
  @app.call(env).tap { |response| write_request(env, response) }
end

#shutdown ⇒ Object

Stops accepting new points and waits (briefly) for the worker to drain whatever is already queued. Safe to call multiple times and safe to call even if the worker was never started.



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# File 'lib/rack/influxdb.rb', line 44

def shutdown
  @queue.close unless @queue.closed?
  @worker&.join(5)
end