Class: OnStomp::Failover::Client

Inherits:
Object
  • Object
show all
Includes:
FailoverConfigurable, FailoverEvents, Interfaces::FrameMethods
Defined in:
lib/onstomp/failover/client.rb

Overview

A failover client that wraps multiple clients and maintains a connection to one of these clients. Frames are sent to the currently connected client. If the connection is lost, a failover client will automatically reconnect to another client in the pool, re-transmit any necessary frames and resume operation.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Interfaces::FrameMethods

#abort, #ack, #beat, #begin, #commit, #nack, #send, #subscribe, #unsubscribe

Methods included from FailoverEvents

#bind_client_event, create_client_event_method, #on_connection_closed, #on_connection_died, #on_connection_established, #on_connection_terminated, #trigger_failover_event, #trigger_failover_retry

Methods included from Interfaces::EventManager

#bind_event, #event_callbacks, included, #trigger_event

Methods included from FailoverConfigurable

included

Constructor Details

#initialize(uris, options = {}) ⇒ Client

Returns a new instance of Client.



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# File 'lib/onstomp/failover/client.rb', line 38

def initialize(uris, options={})
  if uris.is_a? Array
    @uri = OnStomp::Failover::URI::FAILOVER.new [], nil
    @hosts = uris
  else
    @uri = OnStomp::Failover::URI::FAILOVER.parse uris
    @hosts = @uri.failover_uris
  end
  @client_mutex = Mutex.new
  configure_configurable options
  create_client_pool hosts, options
  @active_client = nil
  @connection = nil
  @frame_buffer = buffer.new self
  @disconnecting = false
  retry_ready = false
  @retry_thread = Thread.new do
    until @disconnecting
      retry_ready = true
      Thread.stop
      @client_mutex.synchronize {
        reconnect unless @disconnecting
      }
    end
  end
  Thread.pass until retry_ready && @retry_thread.stop?
end

Instance Attribute Details

#active_client ⇒ Object (readonly)

Returns the value of attribute active_client.



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# File 'lib/onstomp/failover/client.rb', line 35

def active_client
  @active_client
end

#client_pool ⇒ Object (readonly)

Returns the value of attribute client_pool.



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# File 'lib/onstomp/failover/client.rb', line 35

def client_pool
  @client_pool
end

#connection ⇒ Object (readonly)

Returns the value of attribute connection.



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# File 'lib/onstomp/failover/client.rb', line 35

def connection
  @connection
end

#frame_buffer ⇒ Object (readonly)

Returns the value of attribute frame_buffer.



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# File 'lib/onstomp/failover/client.rb', line 35

def frame_buffer
  @frame_buffer
end

#hosts ⇒ Object (readonly)

Returns the value of attribute hosts.



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# File 'lib/onstomp/failover/client.rb', line 35

def hosts
  @hosts
end

#uri ⇒ Object (readonly)

Returns the value of attribute uri.



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# File 'lib/onstomp/failover/client.rb', line 35

def uri
  @uri
end

Instance Method Details

#buffer ⇒ Class

The class to use when instantiating a new frame buffer. Defaults to Buffers::Written

Returns:

  • (Class) 


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# File 'lib/onstomp/failover/client.rb', line 20

attr_configurable_buffer :buffer

#connect ⇒ self

Connects to one of the clients in the #client_pool

Returns:

  • (self) 


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# File 'lib/onstomp/failover/client.rb', line 81

def connect
  @disconnecting = false
  unless @client_mutex.synchronize { reconnect }
    raise OnStomp::Failover::MaximumRetriesExceededError
  end
  self
end

#connected? ⇒ true, ...

Returns true if there is an #active_client and it is connected.

Returns:

  • (true, false, nil) 


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# File 'lib/onstomp/failover/client.rb', line 69

def connected?
  active_client && active_client.connected?
end

#disconnect(*args, &block) ⇒ Object

Ensures that a connection is properly established, then invokes disconnect on the #active_client



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# File 'lib/onstomp/failover/client.rb', line 91

def disconnect *args, &block
  if active_client
    Thread.pass until connected? || @failed
    @client_mutex.synchronize do
      @disconnecting = true
      active_client.disconnect *args, &block if connected?
    end
  end
end

#pool ⇒ Class

The class to use when instantiating a new #client_pool. Defaults to Pools::RoundRobin

Returns:

  • (Class) 


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# File 'lib/onstomp/failover/client.rb', line 16

attr_configurable_pool :pool

#randomize ⇒ true, false

Whether or not to randomize the #client_pool before connecting through any of its clients. Defaults to false

Returns:

  • (true, false) 


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# File 'lib/onstomp/failover/client.rb', line 33

attr_configurable_bool :randomize, :default => false

#retry_attempts ⇒ Fixnum

The maximum number of times to retry connecting during a reconnect loop. A non-positive number will force the failover client to try to reconnect indefinitely. Defaults to 0

Returns:

  • (Fixnum) 


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# File 'lib/onstomp/failover/client.rb', line 29

attr_configurable_int :retry_attempts, :default => 0

#retry_delay ⇒ Fixnum

The delay in seconds to wait between connection retries. Defaults to 10

Returns:

  • (Fixnum) 


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# File 'lib/onstomp/failover/client.rb', line 24

attr_configurable_int :retry_delay, :default => 10

#transmit(frame, cbs = {}) ⇒ OnStomp::Components::Frame?

Transmits a frame to the #active_client if one exists.

Returns:



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# File 'lib/onstomp/failover/client.rb', line 75

def transmit frame, cbs={}
  active_client && active_client.transmit(frame, cbs)
end