Class: Combi::QueueService

Inherits:
Object
  • Object
show all
Defined in:
lib/combi/queue_service.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config, options) ⇒ QueueService

Returns a new instance of QueueService.



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# File 'lib/combi/queue_service.rb', line 9

def initialize(config, options)
  @config = config
  @options = options
  @rpc_queue = nil
  @ready_defer = EventMachine::DefaultDeferrable.new
  @ready_callbacks = []
end

Instance Attribute Details

#rpc_callback ⇒ Object

Returns the value of attribute rpc_callback.



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# File 'lib/combi/queue_service.rb', line 7

def rpc_callback
  @rpc_callback
end

Instance Method Details

#acknowledge(delivery_info) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 92

def acknowledge(delivery_info)
  @channel.acknowledge(delivery_info.delivery_tag, false)
end

#call(kind, message, options = {}) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 116

def call(kind, message, options = {})
  log "sending request #{kind} #{message.inspect[0..500]} with options #{options.inspect}"
  raise "RPC is not enabled or reply_to is not included" if (@rpc_queue.nil? || @rpc_queue.name.nil?) && options[:reply_to].nil?
  options[:expiration] = ((options[:timeout] || RPC_DEFAULT_TIMEOUT) * 1000).to_i
  options[:routing_key] ||= 'rcalls_queue'
  options[:reply_to] ||= @rpc_queue.name
  request = {
    kind: kind,
    payload: message,
    options: {}
  }
  publish(request.to_json, options)
end

#connect(config, &after_connect) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 49

def connect(config, &after_connect)
  puts "[INFO] trying to connect to queue"
  @amqp_conn = AMQP.connect(config) do |connection, open_ok|
    @channel = AMQP::Channel.new @amqp_conn
    @channel.auto_recovery = true
    @exchange = @channel.direct ''
    after_connect.call
    connection.on_error do |conn, connection_close|
      puts "[amqp connection.close] Reply code = #{connection_close.reply_code}, reply text = #{connection_close.reply_text}"
      if connection_close.reply_code == 320
        puts "[amqp connection.close] Setting up a periodic reconnection timer..."
        reconnect
      end
    end
    connection.on_tcp_connection_loss do |conn, settings|
      puts "[ERROR] Connection failed, resetting for reconnect"
      reconnect
    end
  end
end

#create_rpc_queue ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 101

def create_rpc_queue
  @rpc_queue.unsubscribe unless @rpc_queue.nil?
  @rpc_queue = queue('', exclusive: true, auto_delete: true) do |rpc_queue|
    log "\tRPC QUEUE: #{@rpc_queue.name}"
    rpc_queue.subscribe do |metadata, response|
      message = {
        'correlation_id' => metadata.correlation_id,
        'response' => response
      }
      rpc_callback.call(message) unless rpc_callback.nil?
    end
    @ready_defer.succeed
  end
end

#disconnect ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 78

def disconnect
  @amqp_conn.close
end

#log(message) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 30

def log(message)
  return unless @debug_mode ||= ENV['DEBUG'] == 'true'
  puts "#{Time.now.to_f} #{self.class.name} #{message}"
end

#next_ready_only(&block) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 22

def next_ready_only(&block)
  @ready_defer.callback &block
end

#publish(*args, &block) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 82

def publish(*args, &block)
  @exchange.publish *args do
    block.call if block_given?
  end
end

#queue(name, options = {}, &block) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 88

def queue(name, options = {}, &block)
  @channel.queue(name, options, &block)
end

#ready(&block) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 17

def ready(&block)
  @ready_callbacks << block
  @ready_defer.callback &block
end

#reconnect ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 70

def reconnect
  @ready_defer = EventMachine::DefaultDeferrable.new
  @ready_callbacks.each do |callback|
    @ready_defer.callback &callback
  end
  start
end

#respond(response, delivery_info) ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 96

def respond(response, delivery_info)
  response = response.call if response.respond_to? :call
  publish response, routing_key: delivery_info.reply_to, correlation_id: delivery_info.correlation_id
end

#start ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 35

def start
  @config[:reconnect_period] ||= 4
  reconnection_proc = Proc.new { EM.add_timer(@config[:reconnect_period] * rand) { start } }
  @config[:on_tcp_connection_failure] = reconnection_proc
  @config[:on_possible_authentication_failure] = reconnection_proc
  connect @config do
    if @options[:rpc] == :enabled
      create_rpc_queue
    else
      @ready_defer.succeed
    end
  end
end

#status ⇒ Object 



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# File 'lib/combi/queue_service.rb', line 26

def status
  @amqp_conn && @amqp_conn.status
end