File: processor.rb

package info (click to toggle)
ruby-sidekiq 5.2.3%2Bdfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 828 kB
  • sloc: ruby: 4,065; makefile: 24; sh: 6
file content (272 lines) | stat: -rw-r--r-- 7,325 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
# frozen_string_literal: true
require 'sidekiq/util'
require 'sidekiq/fetch'
require 'sidekiq/job_logger'
require 'sidekiq/job_retry'
require 'thread'

module Sidekiq
  ##
  # 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.
  #
  class Processor

    include Util

    attr_reader :thread
    attr_reader :job

    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

    def terminate(wait=false)
      @done = true
      return if !@thread
      @thread.value if wait
    end

    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

    def start
      @thread ||= safe_thread("processor", &method(:run))
    end

    private unless $TESTING

    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

    def process_one
      @job = fetch
      process(@job) if @job
      @job = nil
    end

    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

    def fetch
      j = get_one
      if j && @done
        j.requeue
        nil
      else
        j
      end
    end

    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

    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

    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

    def execute_job(worker, cloned_args)
      worker.perform(*cloned_args)
    end

    # Ruby doesn't provide atomic counters out of the box so we'll
    # implement something simple ourselves.
    # https://bugs.ruby-lang.org/issues/14706
    class Counter
      def initialize
        @value = 0
        @lock = Mutex.new
      end

      def incr(amount=1)
        @lock.synchronize { @value = @value + amount }
      end

      def reset
        @lock.synchronize { val = @value; @value = 0; val }
      end
    end

    # jruby's Hash implementation is not threadsafe, so we wrap it in a mutex here
    class SharedWorkerState
      def initialize
        @worker_state = {}
        @lock = Mutex.new
      end

      def set(tid, hash)
        @lock.synchronize { @worker_state[tid] = hash }
      end

      def delete(tid)
        @lock.synchronize { @worker_state.delete(tid) }
      end

      def dup
        @lock.synchronize { @worker_state.dup }
      end

      def size
        @lock.synchronize { @worker_state.size }
      end

      def clear
        @lock.synchronize { @worker_state.clear }
      end
    end

    PROCESSED = Counter.new
    FAILURE = Counter.new
    WORKER_STATE = SharedWorkerState.new

    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

    # 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.
    def cloned(thing)
      Marshal.load(Marshal.dump(thing))
    end

    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

  end
end