Class: OMQ::Routing::Req

Inherits:
Object
  • Object
show all
Includes:
RoundRobin
Defined in:
lib/omq/routing/req.rb

Overview

REQ socket routing: round-robin send with strict send/recv alternation.

REQ prepends an empty delimiter frame on send and strips it on receive.

Constant Summary collapse

EMPTY_BINARY =

Shared frozen empty binary string to avoid repeated allocations.

::Protocol::ZMTP::Codec::EMPTY_BINARY

Constants included from RoundRobin

OMQ::Routing::RoundRobin::BATCH_BYTE_CAP, OMQ::Routing::RoundRobin::BATCH_MSG_CAP

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from RoundRobin

#send_queues_drained?

Constructor Details

#initialize(engine) ⇒ Req

Returns a new instance of Req.

Parameters:



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# File 'lib/omq/routing/req.rb', line 23

def initialize(engine)
  @engine          = engine
  @recv_queue      = Routing.build_queue(engine.options.recv_hwm, :block)
  @tasks           = []
  @state           = :ready        # :ready or :waiting_reply
  init_round_robin(engine)
end

Instance Attribute Details

#recv_queue ⇒ Async::LimitedQueue (readonly)

Returns:

  • (Async::LimitedQueue) 


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# File 'lib/omq/routing/req.rb', line 18

def recv_queue
  @recv_queue
end

Instance Method Details

#connection_added(connection) ⇒ Object

Parameters:

  • connection (Connection) 


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# File 'lib/omq/routing/req.rb', line 52

def connection_added(connection)
  task = @engine.start_recv_pump(connection, @recv_queue) do |msg|
    @state = :ready
    msg.first&.empty? ? msg[1..] : msg
  end

  @tasks << task if task
  add_round_robin_send_connection(connection)
end

#connection_removed(connection) ⇒ Object

Parameters:

  • connection (Connection) 


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# File 'lib/omq/routing/req.rb', line 65

def connection_removed(connection)
  @connections.delete(connection)
  remove_round_robin_send_connection(connection)
end

#dequeue_recv ⇒ Array<String>?

Dequeues the next received message. Blocks until one is available.

Returns:

  • (Array<String>, nil) 


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# File 'lib/omq/routing/req.rb', line 36

def dequeue_recv
  @recv_queue.dequeue
end

#enqueue(parts) ⇒ Object

Parameters:

  • parts (Array<String>)

Raises:

  • (SocketError) 


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# File 'lib/omq/routing/req.rb', line 73

def enqueue(parts)
  raise SocketError, "REQ socket expects send/recv/send/recv order" unless @state == :ready
  @state = :waiting_reply
  enqueue_round_robin(parts)
end

#stop ⇒ void

This method returns an undefined value.

Stops all background tasks.



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# File 'lib/omq/routing/req.rb', line 84

def stop
  @tasks.each(&:stop)
  @tasks.clear
end

#unblock_recv ⇒ void

This method returns an undefined value.

Wakes a blocked #dequeue_recv with a nil sentinel.



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# File 'lib/omq/routing/req.rb', line 45

def unblock_recv
  @recv_queue.enqueue(nil)
end