Class: BunnyEvents

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

Constant Summary collapse

@@defaults = 
{
  exchange: '',
  exchange_type: :direct,
  routing_key: 'message_queue_event'
}

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#bunny_connection ⇒ Object

Returns the value of attribute bunny_connection.



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# File 'lib/bunny_events.rb', line 4

def bunny_connection
  @bunny_connection
end

#channels ⇒ Object

Returns the value of attribute channels.



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# File 'lib/bunny_events.rb', line 4

def channels
  @channels
end

#initialized_events ⇒ Object

Keeps track of which events have been intiailized by this BunnyEvents worker. Used to ensure that the queue and exchange creation is only performed once.



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# File 'lib/bunny_events.rb', line 8

def initialized_events
  @initialized_events
end

Instance Method Details

#connected? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/bunny_events.rb', line 37

def connected?
  @bunny_connection&.connected? || false
end

#init(bunny_connection) ⇒ Object

Initialise the BunnyEvents system by accepting a bunny connection.

Example:

NOTE: This can also accept bunnymock for testing bunny_events = BunnyEvents.new bunny_events.init BunnyMock.new.start



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# File 'lib/bunny_events.rb', line 24

def init(bunny_connection)
  # Ensure the bunny_connection is valid
  if bunny_connection.nil? || !bunny_connection.respond_to?(:connected?)
    raise Exceptions::InvalidBunnyConnection
  end

  @channels = {}

  @initialized_exchanges = {}

  @bunny_connection = bunny_connection
end

#publish(message, routing_key = nil) ⇒ Object

Public message. message should be an instance of BaseMessage (or a class with BaseMessage included)

Raises:



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# File 'lib/bunny_events.rb', line 42

def publish(message, routing_key = nil)
  unless message.class.included_modules.include?(BunnyEvent)
    raise Exceptions::InvalidBunnyEvent
  end

  raise Exceptions::InvalidBunnyConnection unless connected?

  # get the options defined by the message queue event class
  opts = @@defaults.merge message.class.options

  # Use the class name to determine which channel to use
  unless @channels.key?(message.class.name)
    @channels[message.class.name] = @bunny_connection.create_channel
  end

  channel = @channels[message.class.name]

  #  Ensure that the exchange, queue and binding creation is only performed once
  if !@initialized_exchanges.key?(message.class.name) || opts[:always_create_when_publishing]
    # If the event was sent with an exchange name, create and submit this to the exchange, otherwise, just use the default exchange
    x = if !opts[:exchange].nil? && !opts[:exchange].empty?
          channel.exchange(opts[:exchange], opts[:exchange_opts] || {})
        else
          channel.default_exchange
        end
    # if the event was sent with queue definitions, ensure to create the bindings
    handle_queue_definitions channel, x, opts[:queues] unless opts[:queues].nil?

    # ensure this event's creation params are not processed again
    @initialized_exchanges[message.class.name] ||= x
  end

  x ||= @initialized_exchanges[message.class.name]

  # ensure exchange is not null
  if x.nil? || !@bunny_connection.exchange_exists?(opts[:exchange])
    raise Exceptions::InvalidExchange
  end

  # publish message along with the optional routing key
  x.publish message.message, routing_key: routing_key || opts[:routing_key]
end