Class: Hutch::ErrorHandlers::MaxRetry

Inherits:
Object
  • Object
show all
Includes:
Logging
Defined in:
lib/hutch/error_handlers/max_retry.rb

Overview

When reach the Max Attempts, republish this message to RabbitMQ, And persisted the properties to tell RabbitMQ the ‘x-dead.count`

Instance Method Summary collapse

Instance Method Details

#failure_count(headers, consumer) ⇒ Object 



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# File 'lib/hutch/error_handlers/max_retry.rb', line 61

def failure_count(headers, consumer)
  if headers.nil? || headers['x-death'].nil?
    0
  else
    x_death_array = headers['x-death'].select do |x_death|
      # http://ruby-doc.org/stdlib-2.2.3/libdoc/set/rdoc/Set.html#method-i-intersect-3F
      (x_death['routing-keys'].presence || []).to_set.intersect?(consumer.routing_keys)
    end

    if x_death_array.count > 0 && x_death_array.first['count']
      # Newer versions of RabbitMQ return headers with a count key
      x_death_array.inject(0) { |sum, x_death| sum + x_death['count'] }
    else
      # Older versions return a separate x-death header for each failure
      x_death_array.count
    end
  end
end

#handle(properties, payload, consumer, ex) ⇒ Object

properties.headers example: {

"x-death": [
  {
    "count": 7,
    "exchange": "hutch.topic",
    "queue": "retry_queue",
    "reason": "expired",
    "routing-keys": [
      "plan"
    ],
    "time": "2017-05-13 23:37:15 +0800"
  },
  {
    "count": 7,
    "exchange": "hutch",
    "original-expiration": "3000",
    "queue": "plan_consumer",
    "reason": "rejected",
    "routing-keys": [
      "plan"
    ],
    "time": "2017-05-13 23:37:05 +0800"
  }
]

}



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# File 'lib/hutch/error_handlers/max_retry.rb', line 38

def handle(properties, payload, consumer, ex)
  unless consumer.ancestors.include?(Hutch::Enqueue)
    logger.warn("Consumer: #{consumer} is not include Hutch::Enqueue can`t use #enqueue_in`")
    return false
  end

  prop_headers = properties[:headers] || {}
  attempts     = failure_count(prop_headers, consumer) + 1
  if attempts <= consumer.max_attempts
    logger.debug("retrying, count=#{attempts}, headers:#{prop_headers}")
    # execute_times = attempts - 1
    consumer.enqueue_in(retry_delay(attempts - 1), MultiJson.decode(payload), { headers: prop_headers })
  else
    logger.debug("failing, retry_count=#{attempts}, ex:#{ex}")
  end
end

#retry_delay(executes) ⇒ Object

becareful with the RabbitMQ fixed delay level, this retry_dealy seconds will fit to one fixed delay level. so the max delay time is limit to 3 hours(10800s, error times 11: 14643)



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# File 'lib/hutch/error_handlers/max_retry.rb', line 57

def retry_delay(executes)
  (executes**4) + 2
end