Class: RedisNotifier::Base

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

Constant Summary collapse

NOTIFY_KEYSPACE_EVENTS = 
'notify-keyspace-events'

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(redis, db = 0, keyspace_config = 'KEA', logger = NullLogger.new) ⇒ Base

Returns a new instance of Base.



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# File 'lib/redis_notifier.rb', line 21

def initialize(redis, db=0, keyspace_config='KEA', logger=NullLogger.new)
  @logger = logger
  @db = db.to_s
  @redis = redis
  redis.config(:set, NOTIFY_KEYSPACE_EVENTS, keyspace_config)
  @callbacks = { key: {}, event: {} }
  @listened_channels = []
end

Instance Attribute Details

#callbacks ⇒ Object (readonly)

Returns the value of attribute callbacks.



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# File 'lib/redis_notifier.rb', line 19

def callbacks
  @callbacks
end

#db ⇒ Object (readonly)

Returns the value of attribute db.



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# File 'lib/redis_notifier.rb', line 19

def db
  @db
end

#listened_channels ⇒ Object (readonly)

Returns the value of attribute listened_channels.



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# File 'lib/redis_notifier.rb', line 19

def listened_channels
  @listened_channels
end

#logger ⇒ Object (readonly)

Returns the value of attribute logger.



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# File 'lib/redis_notifier.rb', line 19

def logger
  @logger
end

#redis ⇒ Object (readonly)

Returns the value of attribute redis.



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# File 'lib/redis_notifier.rb', line 19

def redis
  @redis
end

Instance Method Details

#build_channel_for(type, prefix) ⇒ Object 



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# File 'lib/redis_notifier.rb', line 46

def build_channel_for(type, prefix)
  namespace = case type
  when :event
    'keyevent'
  when :key
    'keyspace'
  end
  "__#{namespace}@#{db}__:#{prefix}"
end

#find_type_from(channel) ⇒ Object 



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# File 'lib/redis_notifier.rb', line 56

def find_type_from(channel)
  if channel.include?('__keyevent@')
    :event
  elsif channel.include?('__keyspace@')
    :key
  else
    nil
  end
end

#listen ⇒ Object 



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# File 'lib/redis_notifier.rb', line 66

def listen
  logger.debug("listened channels: #{listened_channels}")
  redis.subscribe(listened_channels) do |on|
    on.message do |ch, msg|
      logger.debug("message received: channel=#{ch}; msg=#{msg}")

      extracted_key = ch.split(':')[1..-1].join(':')

      logger.debug("extracted key: #{extracted_key}")

      if type = find_type_from(ch)
        callbacks[type][extracted_key].call(msg)
      else
        logger.warn("message received but not in keyspace or keyevent")
      end

    end
  end
end

#observe_key(key, &block) ⇒ Object 



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# File 'lib/redis_notifier.rb', line 34

def observe_key(key, &block)
  on :key, key, &block
end

#on(type, prefix, &block) ⇒ Object

Raises:



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# File 'lib/redis_notifier.rb', line 38

def on(type, prefix, &block)
  raise NoBlockGiven unless block_given?
  channel = build_channel_for(type, prefix)
  return if @listened_channels.include?(channel)
  @listened_channels << channel
  @callbacks[type][prefix.to_s] = block
end

#on_event(event_name, &block) ⇒ Object 



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# File 'lib/redis_notifier.rb', line 30

def on_event(event_name, &block)
  on :event, event_name, &block
end