Parent

Object

ConnectionPool

Generic connection pool class for e.g. sharing a limited number of network connections among many threads. Note: Connections are eager created.

Example usage with block (faster):

@pool = ConnectionPool.new { Redis.new }

@pool.with do |redis|
  redis.lpop('my-list') if redis.llen('my-list') > 0
end

Using optional timeout override (for that single invocation)

@pool.with(:timeout => 2.0) do |redis|
  redis.lpop('my-list') if redis.llen('my-list') > 0
end

Example usage replacing an existing connection (slower):

$redis = ConnectionPool.wrap { Redis.new }

def do_work
  $redis.lpop('my-list') if $redis.llen('my-list') > 0
end

Accepts the following options:

Constants

DEFAULTS
VERSION

Public Class Methods

new(options = {}, &block) click to toggle source 
# File lib/connection_pool.rb, line 43
def initialize(options = {}, &block)
  raise ArgumentError, 'Connection pool requires a block' unless block

  options = DEFAULTS.merge(options)

  @size = options.fetch(:size)
  @timeout = options.fetch(:timeout)

  @available = TimedStack.new(@size, &block)
  @key = :"current-#{@available.object_id}"
end
wrap(options, &block) click to toggle source 
# File lib/connection_pool.rb, line 39
def self.wrap(options, &block)
  Wrapper.new(options, &block)
end

Public Instance Methods

checkin() click to toggle source 
# File lib/connection_pool.rb, line 78
def checkin
  stack = ::Thread.current[@key]
  raise ConnectionPool::Error, 'no connections are checked out' if
    !stack || stack.empty?

  conn = stack.pop
  if stack.empty?
    @available << conn
  end
  nil
end
checkout(options = {}) click to toggle source 
# File lib/connection_pool.rb, line 64
def checkout(options = {})
  stack = ::Thread.current[@key] ||= []

  if stack.empty?
    timeout = options[:timeout] || @timeout
    conn = @available.pop(timeout)
  else
    conn = stack.last
  end

  stack.push conn
  conn
end
shutdown(&block) click to toggle source 
# File lib/connection_pool.rb, line 90
def shutdown(&block)
  @available.shutdown(&block)
end
with(options = {}) click to toggle source 
# File lib/connection_pool.rb, line 55
def with(options = {})
  conn = checkout(options)
  begin
    yield conn
  ensure
    checkin
  end
end

[Validate]

Generated with the Darkfish Rdoc Generator 2.