Welcome to mirror list, hosted at ThFree Co, Russian Federation.

sidekiq_monitor.rb « gitlab « lib - gitlab.com/gitlab-org/gitlab-foss.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
blob: bfbf998b3a09edd6384b3f6cc406d0389ab0a083 (plain)
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
# frozen_string_literal: true

module Gitlab
  class SidekiqMonitor < Daemon
    include ::Gitlab::Utils::StrongMemoize

    NOTIFICATION_CHANNEL = 'sidekiq:cancel:notifications'.freeze
    CANCEL_DEADLINE = 24.hours.seconds

    # We use exception derived from `Exception`
    # to consider this as an very low-level exception
    # that should not be caught by application
    CancelledError = Class.new(Exception) # rubocop:disable Lint/InheritException

    attr_reader :jobs_thread
    attr_reader :jobs_mutex

    def initialize
      super

      @jobs_thread = {}
      @jobs_mutex = Mutex.new
    end

    def within_job(jid, queue)
      jobs_mutex.synchronize do
        jobs_thread[jid] = Thread.current
      end

      if cancelled?(jid)
        Sidekiq.logger.warn(
          class: self.class,
          action: 'run',
          queue: queue,
          jid: jid,
          canceled: true)
        raise CancelledError
      end

      yield
    ensure
      jobs_mutex.synchronize do
        jobs_thread.delete(jid)
      end
    end

    def start_working
      Sidekiq.logger.info(
        class: self.class,
        action: 'start',
        message: 'Starting Monitor Daemon')

      ::Gitlab::Redis::SharedState.with do |redis|
        redis.subscribe(NOTIFICATION_CHANNEL) do |on|
          on.message do |channel, message|
            process_message(message)
          end
        end
      end

      Sidekiq.logger.warn(
        class: self.class,
        action: 'stop',
        message: 'Stopping Monitor Daemon')
    rescue Exception => e # rubocop:disable Lint/RescueException
      Sidekiq.logger.warn(
        class: self.class,
        action: 'exception',
        message: e.message)
      raise e
    end

    def self.cancel_job(jid)
      payload = {
        action: 'cancel',
        jid: jid
      }.to_json

      ::Gitlab::Redis::SharedState.with do |redis|
        redis.setex(cancel_job_key(jid), CANCEL_DEADLINE, 1)
        redis.publish(NOTIFICATION_CHANNEL, payload)
      end
    end

    private

    def process_message(message)
      Sidekiq.logger.info(
        class: self.class,
        channel: NOTIFICATION_CHANNEL,
        message: 'Received payload on channel',
        payload: message)

      message = safe_parse(message)
      return unless message

      case message['action']
      when 'cancel'
        process_job_cancel(message['jid'])
      else
        # unknown message
      end
    end

    def safe_parse(message)
      JSON.parse(message)
    rescue JSON::ParserError
    end

    def process_job_cancel(jid)
      return unless jid

      # try to find thread without lock
      return unless find_thread_unsafe(jid)

      Thread.new do
        # try to find a thread, but with guaranteed
        # handle that this thread corresponds to actually running job
        find_thread_with_lock(jid) do |thread|
          Sidekiq.logger.warn(
            class: self.class,
            action: 'cancel',
            message: 'Canceling thread with CancelledError',
            jid: jid,
            thread_id: thread.object_id)

          thread&.raise(CancelledError)
        end
      end
    end

    # This method needs to be thread-safe
    # This is why it passes thread in block,
    # to ensure that we do process this thread
    def find_thread_unsafe(jid)
      jobs_thread[jid]
    end

    def find_thread_with_lock(jid)
      # don't try to lock if we cannot find the thread
      return unless find_thread_unsafe(jid)

      jobs_mutex.synchronize do
        find_thread_unsafe(jid).tap do |thread|
          yield(thread) if thread
        end
      end
    end

    def cancelled?(jid)
      ::Gitlab::Redis::SharedState.with do |redis|
        redis.exists(self.class.cancel_job_key(jid))
      end
    end

    def self.cancel_job_key(jid)
      "sidekiq:cancel:#{jid}"
    end
  end
end