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 32
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 50
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 62
def start
  @thread ||= safe_thread("processor", &method(:run))
end
terminate(wait=false) click to toggle source
# File lib/sidekiq/processor.rb, line 44
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 263
def cloned(thing)
  Marshal.load(Marshal.dump(thing))
end
constantize(str) click to toggle source
# File lib/sidekiq/processor.rb, line 267
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 118
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 191
def execute_job(worker, cloned_args)
  worker.perform(*cloned_args)
end
fetch() click to toggle source
# File lib/sidekiq/processor.rb, line 98
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 87
def get_one
  begin
    work = @strategy.retrieve_work
    (logger.info { "Redis is online, #{::Process.clock_gettime(::Process::CLOCK_MONOTONIC) - @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 108
def handle_fetch_exception(ex)
  if !@down
    @down = ::Process.clock_gettime(::Process::CLOCK_MONOTONIC)
    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 146
def process(work)
  jobstr = work.job
  queue = work.queue_name

  # 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)
    return work.acknowledge
  end

  ack = true
  begin
    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 Sidekiq::JobRetry::Handled => h
    # this is the common case: job raised error and Sidekiq::JobRetry::Handled
    # signals that we created a retry successfully.  We can acknowlege the job.
    e = h.cause ? h.cause : h
    handle_exception(e, { :context => "Job raised exception", :job => job_hash, :jobstr => jobstr })
    raise e
  rescue Exception => ex
    # Unexpected error!  This is very bad and indicates an exception that got past
    # the retry subsystem (e.g. network partition).  We won't acknowledge the job
    # so it can be rescued when using Sidekiq Pro.
    ack = false
    handle_exception(ex, { :context => "Internal 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 81
def process_one
  @job = fetch
  process(@job) if @job
  @job = nil
end
run() click to toggle source
# File lib/sidekiq/processor.rb, line 68
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 245
def stats(job_hash, queue)
  tid = Sidekiq::Logging.tid
  WORKER_STATE.set(tid, {:queue => queue, :payload => job_hash, :run_at => Time.now.to_i })

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