Add latest changes from gitlab-org/gitlab@master

1 files changed, 101 insertions, 0 deletions

diff --git a/app/workers/concerns/reenqueuer.rb b/app/workers/concerns/reenqueuer.rb
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+++ b/app/workers/concerns/reenqueuer.rb
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+# frozen_string_literal: true
+
+#
+# A concern that helps run exactly one instance of a worker, over and over,
+# until it returns false or raises.
+#
+# To ensure the worker is always up, you can schedule it every minute with
+# sidekiq-cron. Excess jobs will immediately exit due to an exclusive lease.
+#
+# The worker must define:
+#
+#   - `#perform`
+#   - `#lease_timeout`
+#
+# The worker spec should include `it_behaves_like 'reenqueuer'` and
+# `it_behaves_like 'it is rate limited to 1 call per'`.
+#
+# Optionally override `#minimum_duration` to adjust the rate limit.
+#
+# When `#perform` returns false, the job will not be reenqueued. Instead, we
+# will wait for the next one scheduled by sidekiq-cron.
+#
+# #lease_timeout should be longer than the longest possible `#perform`.
+# The lease is normally released in an ensure block, but it is possible to
+# orphan the lease by killing Sidekiq, so it should also be as short as
+# possible. Consider that long-running jobs are generally not recommended.
+# Ideally, every job finishes within 25 seconds because that is the default
+# wait time for graceful termination.
+#
+# Timing: It runs as often as Sidekiq allows. We rate limit with sleep for
+# now: https://gitlab.com/gitlab-org/gitlab/issues/121697
+module Reenqueuer
+  extend ActiveSupport::Concern
+
+  prepended do
+    include ExclusiveLeaseGuard
+    include ReenqueuerSleeper
+
+    sidekiq_options retry: false
+  end
+
+  def perform(*args)
+    try_obtain_lease do
+      reenqueue(*args) do
+        ensure_minimum_duration(minimum_duration) do
+          super
+        end
+      end
+    end
+  end
+
+  private
+
+  def reenqueue(*args)
+    self.class.perform_async(*args) if yield
+  end
+
+  # Override as needed
+  def minimum_duration
+    5.seconds
+  end
+
+  # We intend to get rid of sleep:
+  # https://gitlab.com/gitlab-org/gitlab/issues/121697
+  module ReenqueuerSleeper
+    # The block will run, and then sleep until the minimum duration. Returns the
+    # block's return value.
+    #
+    # Usage:
+    #
+    #   ensure_minimum_duration(5.seconds) do
+    #     # do something
+    #   end
+    #
+    def ensure_minimum_duration(minimum_duration)
+      start_time = Time.now
+
+      result = yield
+
+      sleep_if_time_left(minimum_duration, start_time)
+
+      result
+    end
+
+    private
+
+    def sleep_if_time_left(minimum_duration, start_time)
+      time_left = calculate_time_left(minimum_duration, start_time)
+
+      sleep(time_left) if time_left > 0
+    end
+
+    def calculate_time_left(minimum_duration, start_time)
+      minimum_duration - elapsed_time(start_time)
+    end
+
+    def elapsed_time(start_time)
+      Time.now - start_time
+    end
+  end
+end