Class: Dalli::Server

Inherits:
Object
  • Object
show all
Defined in:
lib/dalli/server.rb

Constant Summary collapse

DEFAULTS = 
{
  # seconds between trying to contact a remote server
  :down_retry_delay => 1,
  # connect/read/write timeout for socket operations
  :socket_timeout => 0.5,
  # times a socket operation may fail before considering the server dead
  :socket_max_failures => 2,
  # amount of time to sleep between retries when a failure occurs
  :socket_failure_delay => 0.01,
  # max size of value in bytes (default is 1 MB, can be overriden with "memcached -I <size>")
  :value_max_bytes => 1024 * 1024,
  :username => nil,
  :password => nil,
  :keepalive => true
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(attribs, options = {}) ⇒ Server

Returns a new instance of Server.



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# File 'lib/dalli/server.rb', line 28

def initialize(attribs, options = {})
  (@hostname, @port, @weight) = attribs.split(':')
  @port ||= 11211
  @port = Integer(@port)
  @weight ||= 1
  @weight = Integer(@weight)
  @fail_count = 0
  @down_at = nil
  @last_down_at = nil
  @options = DEFAULTS.merge(options)
  @sock = nil
  @msg = nil
  @pid = nil
end

Instance Attribute Details

#hostname ⇒ Object

Returns the value of attribute hostname.



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# File 'lib/dalli/server.rb', line 7

def hostname
  @hostname
end

#options ⇒ Object

Returns the value of attribute options.



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# File 'lib/dalli/server.rb', line 10

def options
  @options
end

#port ⇒ Object

Returns the value of attribute port.



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# File 'lib/dalli/server.rb', line 8

def port
  @port
end

#weight ⇒ Object

Returns the value of attribute weight.



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# File 'lib/dalli/server.rb', line 9

def weight
  @weight
end

Instance Method Details

#alive? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dalli/server.rb', line 66

def alive?
  return true if @sock

  if @last_down_at && @last_down_at + options[:down_retry_delay] >= Time.now
    time = @last_down_at + options[:down_retry_delay] - Time.now
    Dalli.logger.debug { "down_retry_delay not reached for #{hostname}:#{port} (%.3f seconds left)" % time }
    return false
  end

  connect
  !!@sock
rescue Dalli::NetworkError
  false
end

#close ⇒ Object 



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# File 'lib/dalli/server.rb', line 81

def close
  return unless @sock
  @sock.close rescue nil
  @sock = nil
  @pid = nil
  @inprogress = false
end

#lock! ⇒ Object 



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# File 'lib/dalli/server.rb', line 89

def lock!
end

#request(op, *args) ⇒ Object

Chokepoint method for instrumentation

Raises:



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# File 'lib/dalli/server.rb', line 44

def request(op, *args)
  verify_state
  raise Dalli::NetworkError, "#{hostname}:#{port} is down: #{@error} #{@msg}" unless alive?
  begin
    send(op, *args)
  rescue Dalli::NetworkError
    raise
  rescue Dalli::MarshalError => ex
    Dalli.logger.error "Marshalling error for key '#{args.first}': #{ex.message}"
    Dalli.logger.error "You are trying to cache a Ruby object which cannot be serialized to memcached."
    Dalli.logger.error ex.backtrace.join("\n\t")
    false
  rescue Dalli::DalliError
    raise
  rescue => ex
    Dalli.logger.error "Unexpected exception in Dalli: #{ex.class.name}: #{ex.message}"
    Dalli.logger.error "This is a bug in Dalli, please enter an issue in Github if it does not already exist."
    Dalli.logger.error ex.backtrace.join("\n\t")
    down!
  end
end

#unlock! ⇒ Object 



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# File 'lib/dalli/server.rb', line 92

def unlock!
end