Add latest changes from gitlab-org/gitlab@master

3 files changed, 113 insertions, 39 deletions

diff --git a/lib/gitlab/cluster/lifecycle_events.rb b/lib/gitlab/cluster/lifecycle_events.rb
index f931a94938f..2b3dc94fc5e 100644
--- a/lib/gitlab/cluster/lifecycle_events.rb
+++ b/lib/gitlab/cluster/lifecycle_events.rb
@@ -10,38 +10,39 @@ module Gitlab
     #
     # We have the following lifecycle events.
     #
-    # - on_master_start:
+    # - on_before_fork (on master process):
     #
     #     Unicorn/Puma Cluster: This will be called exactly once,
     #       on startup, before the workers are forked. This is
     #       called in the PARENT/MASTER process.
     #
-    #     Sidekiq/Puma Single: This is called immediately.
+    #     Sidekiq/Puma Single: This is not called.
     #
-    # - on_before_fork:
+    # - on_master_start (on master process):
     #
     #     Unicorn/Puma Cluster: This will be called exactly once,
     #       on startup, before the workers are forked. This is
     #       called in the PARENT/MASTER process.
     #
-    #     Sidekiq/Puma Single: This is not called.
+    #     Sidekiq/Puma Single: This is called immediately.
     #
-    # - on_worker_start:
+    # - on_before_blackout_period (on master process):
     #
-    #     Unicorn/Puma Cluster: This is called in the worker process
-    #       exactly once before processing requests.
+    #     Unicorn/Puma Cluster: This will be called before a blackout
+    #       period when performing graceful shutdown of master.
+    #       This is called on `master` process.
     #
-    #     Sidekiq/Puma Single: This is called immediately.
+    #     Sidekiq/Puma Single: This is not called.
     #
-    # - on_before_graceful_shutdown:
+    # - on_before_graceful_shutdown (on master process):
     #
     #     Unicorn/Puma Cluster: This will be called before a graceful
-    #       shutdown of workers starts happening.
+    #       shutdown  of workers starts happening, but after blackout period.
     #       This is called on `master` process.
     #
     #     Sidekiq/Puma Single: This is not called.
     #
-    # - on_before_master_restart:
+    # - on_before_master_restart (on master process):
     #
     #     Unicorn: This will be called before a new master is spun up.
     #       This is called on forked master before `execve` to become
@@ -53,6 +54,13 @@ module Gitlab
     #
     #     Sidekiq/Puma Single: This is not called.
     #
+    # - on_worker_start (on worker process):
+    #
+    #     Unicorn/Puma Cluster: This is called in the worker process
+    #       exactly once before processing requests.
+    #
+    #     Sidekiq/Puma Single: This is called immediately.
+    #
     # Blocks will be executed in the order in which they are registered.
     #
     class LifecycleEvents
@@ -75,6 +83,12 @@ module Gitlab
         end
 
         # Read the config/initializers/cluster_events_before_phased_restart.rb
+        def on_before_blackout_period(&block)
+          # Defer block execution
+          (@master_blackout_period ||= []) << block
+        end
+
+        # Read the config/initializers/cluster_events_before_phased_restart.rb
         def on_before_graceful_shutdown(&block)
           # Defer block execution
           (@master_graceful_shutdown ||= []) << block
@@ -97,27 +111,24 @@ module Gitlab
         # Lifecycle integration methods (called from unicorn.rb, puma.rb, etc.)
         #
         def do_worker_start
-          @worker_start_hooks&.each do |block|
-            block.call
-          end
+          call(@worker_start_hooks)
         end
 
         def do_before_fork
-          @before_fork_hooks&.each do |block|
-            block.call
-          end
+          call(@before_fork_hooks)
         end
 
         def do_before_graceful_shutdown
-          @master_graceful_shutdown&.each do |block|
-            block.call
-          end
+          call(@master_blackout_period)
+
+          blackout_seconds = ::Settings.shutdown.blackout_seconds.to_i
+          sleep(blackout_seconds) if blackout_seconds > 0
+
+          call(@master_graceful_shutdown)
         end
 
         def do_before_master_restart
-          @master_restart_hooks&.each do |block|
-            block.call
-          end
+          call(@master_restart_hooks)
         end
 
         # DEPRECATED
@@ -132,6 +143,10 @@ module Gitlab
 
         private
 
+        def call(hooks)
+          hooks&.each(&:call)
+        end
+
         def in_clustered_environment?
           # Sidekiq doesn't fork
           return false if Sidekiq.server?
diff --git a/lib/gitlab/health_checks/master_check.rb b/lib/gitlab/health_checks/master_check.rb
new file mode 100644
index 00000000000..057bce84ddd
--- /dev/null
+++ b/lib/gitlab/health_checks/master_check.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module HealthChecks
+    # This check is registered on master,
+    # and validated by worker
+    class MasterCheck
+      extend SimpleAbstractCheck
+
+      class << self
+        def register_master
+          # when we fork, we pass the read pipe to child
+          # child can then react on whether the other end
+          # of pipe is still available
+          @pipe_read, @pipe_write = IO.pipe
+        end
+
+        def finish_master
+          close_read
+          close_write
+        end
+
+        def register_worker
+          # fork needs to close the pipe
+          close_write
+        end
+
+        private
+
+        def close_read
+          @pipe_read&.close
+          @pipe_read = nil
+        end
+
+        def close_write
+          @pipe_write&.close
+          @pipe_write = nil
+        end
+
+        def metric_prefix
+          'master_check'
+        end
+
+        def successful?(result)
+          result
+        end
+
+        def check
+          # the lack of pipe is a legitimate failure of check
+          return false unless @pipe_read
+
+          @pipe_read.read_nonblock(1)
+
+          true
+        rescue IO::EAGAINWaitReadable
+          # if it is blocked, it means that the pipe is still open
+          # and there's no data waiting on it
+          true
+        rescue EOFError
+          # the pipe is closed
+          false
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/metrics/exporter/web_exporter.rb b/lib/gitlab/metrics/exporter/web_exporter.rb
index 3940f6fa155..b6a27d8556a 100644
--- a/lib/gitlab/metrics/exporter/web_exporter.rb
+++ b/lib/gitlab/metrics/exporter/web_exporter.rb
@@ -20,6 +20,10 @@ module Gitlab
         def initialize
           super
 
+          # DEPRECATED:
+          # these `readiness_checks` are deprecated
+          # as presenting no value in a way how we run
+          # application: https://gitlab.com/gitlab-org/gitlab/issues/35343
           self.readiness_checks = [
             WebExporter::ExporterCheck.new(self),
             Gitlab::HealthChecks::PumaCheck,
@@ -35,6 +39,10 @@ module Gitlab
           File.join(Rails.root, 'log', 'web_exporter.log')
         end
 
+        def mark_as_not_running!
+          @running = false
+        end
+
         private
 
         def start_working
@@ -43,24 +51,9 @@ module Gitlab
         end
 
         def stop_working
-          @running = false
-          wait_in_blackout_period if server && thread.alive?
+          mark_as_not_running!
           super
         end
-
-        def wait_in_blackout_period
-          return unless blackout_seconds > 0
-
-          @server.logger.info(
-            message: 'starting blackout...',
-            duration_s: blackout_seconds)
-
-          sleep(blackout_seconds)
-        end
-
-        def blackout_seconds
-          settings['blackout_seconds'].to_i
-        end
       end
     end
   end