class Sidekiq::Processor

The Processor is a standalone thread which:

  1. fetches a job from Redis

  2. executes the job

a. instantiate the Worker
b. run the middleware chain
c. call #perform

A Processor can exit due to shutdown (processor_stopped) or due to an error during job execution (processor_died)

If an error occurs in the job execution, the Processor calls the Manager to create a new one to replace itself and exits.

Constants

FAILURE
PROCESSED
WORKER_STATE

Attributes

job[R]
thread[R]

Public Class Methods

new(mgr) click to toggle source
# File lib/sidekiq/processor.rb, line 33
def initialize(mgr)
  @mgr = mgr
  @down = false
  @done = false
  @job = nil
  @thread = nil
  @strategy = (mgr.options[:fetch] || Sidekiq::BasicFetch).new(mgr.options)
  @reloader = Sidekiq.options[:reloader]
  @logging = (mgr.options[:job_logger] || Sidekiq::JobLogger).new
  @retrier = Sidekiq::JobRetry.new
end

Public Instance Methods

kill(wait=false) click to toggle source
# File lib/sidekiq/processor.rb, line 51
def kill(wait=false)
  @done = true
  return if !@thread
  # unlike the other actors, terminate does not wait
  # for the thread to finish because we don't know how
  # long the job will take to finish.  Instead we
  # provide a `kill` method to call after the shutdown
  # timeout passes.
  @thread.raise ::Sidekiq::Shutdown
  @thread.value if wait
end
start() click to toggle source
# File lib/sidekiq/processor.rb, line 63
def start
  @thread ||= safe_thread("processor", &method(:run))
end
terminate(wait=false) click to toggle source
# File lib/sidekiq/processor.rb, line 45
def terminate(wait=false)
  @done = true
  return if !@thread
  @thread.value if wait
end

Private Instance Methods

cloned(thing) click to toggle source

Deep clone the arguments passed to the worker so that if the job fails, what is pushed back onto Redis hasn't been mutated by the worker.

# File lib/sidekiq/processor.rb, line 211
def cloned(thing)
  Marshal.load(Marshal.dump(thing))
end
constantize(str) click to toggle source
# File lib/sidekiq/processor.rb, line 215
def constantize(str)
  names = str.split('::')
  names.shift if names.empty? || names.first.empty?

  names.inject(Object) do |constant, name|
    # the false flag limits search for name to under the constant namespace
    #   which mimics Rails' behaviour
    constant.const_defined?(name, false) ? constant.const_get(name, false) : constant.const_missing(name)
  end
end
dispatch(job_hash, queue) { |worker| ... } click to toggle source
# File lib/sidekiq/processor.rb, line 119
def dispatch(job_hash, queue)
  # since middleware can mutate the job hash
  # we clone here so we report the original
  # job structure to the Web UI
  pristine = cloned(job_hash)

  Sidekiq::Logging.with_job_hash_context(job_hash) do
    @retrier.global(pristine, queue) do
      @logging.call(job_hash, queue) do
        stats(pristine, queue) do
          # Rails 5 requires a Reloader to wrap code execution.  In order to
          # constantize the worker and instantiate an instance, we have to call
          # the Reloader.  It handles code loading, db connection management, etc.
          # Effectively this block denotes a "unit of work" to Rails.
          @reloader.call do
            klass  = constantize(job_hash['class'])
            worker = klass.new
            worker.jid = job_hash['jid']
            @retrier.local(worker, pristine, queue) do
              yield worker
            end
          end
        end
      end
    end
  end
end
execute_job(worker, cloned_args) click to toggle source
# File lib/sidekiq/processor.rb, line 185
def execute_job(worker, cloned_args)
  worker.perform(*cloned_args)
end
fetch() click to toggle source
# File lib/sidekiq/processor.rb, line 99
def fetch
  j = get_one
  if j && @done
    j.requeue
    nil
  else
    j
  end
end
get_one() click to toggle source
# File lib/sidekiq/processor.rb, line 88
def get_one
  begin
    work = @strategy.retrieve_work
    (logger.info { "Redis is online, #{Time.now - @down} sec downtime" }; @down = nil) if @down
    work
  rescue Sidekiq::Shutdown
  rescue => ex
    handle_fetch_exception(ex)
  end
end
handle_fetch_exception(ex) click to toggle source
# File lib/sidekiq/processor.rb, line 109
def handle_fetch_exception(ex)
  if !@down
    @down = Time.now
    logger.error("Error fetching job: #{ex}")
    handle_exception(ex)
  end
  sleep(1)
  nil
end
process(work) click to toggle source
# File lib/sidekiq/processor.rb, line 147
def process(work)
  jobstr = work.job
  queue = work.queue_name

  ack = false
  begin
    # Treat malformed JSON as a special case: job goes straight to the morgue.
    job_hash = nil
    begin
      job_hash = Sidekiq.load_json(jobstr)
    rescue => ex
      handle_exception(ex, { :context => "Invalid JSON for job", :jobstr => jobstr })
      # we can't notify because the job isn't a valid hash payload.
      DeadSet.new.kill(jobstr, notify_failure: false)
      ack = true
      raise
    end

    ack = true
    dispatch(job_hash, queue) do |worker|
      Sidekiq.server_middleware.invoke(worker, job_hash, queue) do
        execute_job(worker, cloned(job_hash['args']))
      end
    end
  rescue Sidekiq::Shutdown
    # Had to force kill this job because it didn't finish
    # within the timeout.  Don't acknowledge the work since
    # we didn't properly finish it.
    ack = false
  rescue Exception => ex
    e = ex.is_a?(::Sidekiq::JobRetry::Skip) && ex.cause ? ex.cause : ex
    handle_exception(e, { :context => "Job raised exception", :job => job_hash, :jobstr => jobstr })
    raise e
  ensure
    work.acknowledge if ack
  end
end
process_one() click to toggle source
# File lib/sidekiq/processor.rb, line 82
def process_one
  @job = fetch
  process(@job) if @job
  @job = nil
end
run() click to toggle source
# File lib/sidekiq/processor.rb, line 69
def run
  begin
    while !@done
      process_one
    end
    @mgr.processor_stopped(self)
  rescue Sidekiq::Shutdown
    @mgr.processor_stopped(self)
  rescue Exception => ex
    @mgr.processor_died(self, ex)
  end
end
stats(job_hash, queue) { || ... } click to toggle source
# File lib/sidekiq/processor.rb, line 193
def stats(job_hash, queue)
  tid = Sidekiq::Logging.tid
  WORKER_STATE[tid] = {:queue => queue, :payload => job_hash, :run_at => Time.now.to_i }

  begin
    yield
  rescue Exception
    FAILURE.increment
    raise
  ensure
    WORKER_STATE.delete(tid)
    PROCESSED.increment
  end
end