Add latest changes from gitlab-org/gitlab@master

5 files changed, 85 insertions, 4 deletions

diff --git a/lib/gitlab/health_checks/gitaly_check.rb b/lib/gitlab/health_checks/gitaly_check.rb
index f5f142c251f..e780bf8a986 100644
--- a/lib/gitlab/health_checks/gitaly_check.rb
+++ b/lib/gitlab/health_checks/gitaly_check.rb
@@ -5,7 +5,7 @@ module Gitlab
     class GitalyCheck
       extend BaseAbstractCheck
 
-      METRIC_PREFIX = 'gitaly_health_check'
+      METRIC_PREFIX = 'gitaly_health_check'.freeze
 
       class << self
         def readiness
diff --git a/lib/gitlab/health_checks/probes/readiness.rb b/lib/gitlab/health_checks/probes/readiness.rb
index b789cbe1ae6..28abf490ffc 100644
--- a/lib/gitlab/health_checks/probes/readiness.rb
+++ b/lib/gitlab/health_checks/probes/readiness.rb
@@ -6,10 +6,10 @@ module Gitlab
       class Readiness
         attr_reader :checks
 
-        # This accepts an array of Proc
+        # This accepts an array of objects implementing `:readiness`
         # that returns `::Gitlab::HealthChecks::Result`
         def initialize(*additional_checks)
-          @checks = ::Gitlab::HealthChecks::CHECKS.map { |check| check.method(:readiness) }
+          @checks = ::Gitlab::HealthChecks::CHECKS
           @checks += additional_checks
         end
 
@@ -43,7 +43,7 @@ module Gitlab
 
         def probe_readiness
           checks
-            .flat_map(&:call)
+            .flat_map(&:readiness)
             .compact
             .group_by(&:name)
         end
diff --git a/lib/gitlab/health_checks/puma_check.rb b/lib/gitlab/health_checks/puma_check.rb
new file mode 100644
index 00000000000..7aafe29fbae
--- /dev/null
+++ b/lib/gitlab/health_checks/puma_check.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module HealthChecks
+    # This check can only be run on Puma `master` process
+    class PumaCheck
+      extend SimpleAbstractCheck
+
+      class << self
+        private
+
+        def metric_prefix
+          'puma_check'
+        end
+
+        def successful?(result)
+          result > 0
+        end
+
+        def check
+          return unless defined?(::Puma)
+
+          stats = Puma.stats
+          stats = JSON.parse(stats)
+
+          # If `workers` is missing this means that
+          # Puma server is running in single mode
+          stats.fetch('workers', 1)
+        rescue NoMethodError
+          # server is not ready
+          0
+        end
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/health_checks/simple_abstract_check.rb b/lib/gitlab/health_checks/simple_abstract_check.rb
index 959f28791c3..4e0b9296819 100644
--- a/lib/gitlab/health_checks/simple_abstract_check.rb
+++ b/lib/gitlab/health_checks/simple_abstract_check.rb
@@ -7,6 +7,8 @@ module Gitlab
 
       def readiness
         check_result = check
+        return if check_result.nil?
+
         if successful?(check_result)
           HealthChecks::Result.new(name, true)
         elsif check_result.is_a?(Timeout::Error)
@@ -20,6 +22,8 @@ module Gitlab
 
       def metrics
         result, elapsed = with_timing(&method(:check))
+        return if result.nil?
+
         Rails.logger.error("#{human_name} check returned unexpected result #{result}") unless successful?(result) # rubocop:disable Gitlab/RailsLogger
         [
           metric("#{metric_prefix}_timeout", result.is_a?(Timeout::Error) ? 1 : 0),
diff --git a/lib/gitlab/health_checks/unicorn_check.rb b/lib/gitlab/health_checks/unicorn_check.rb
new file mode 100644
index 00000000000..a30ae015257
--- /dev/null
+++ b/lib/gitlab/health_checks/unicorn_check.rb
@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+
+module Gitlab
+  module HealthChecks
+    # This check can only be run on Unicorn `master` process
+    class UnicornCheck
+      extend SimpleAbstractCheck
+
+      class << self
+        include Gitlab::Utils::StrongMemoize
+
+        private
+
+        def metric_prefix
+          'unicorn_check'
+        end
+
+        def successful?(result)
+          result > 0
+        end
+
+        def check
+          return unless http_servers
+
+          http_servers.sum(&:worker_processes) # rubocop: disable CodeReuse/ActiveRecord
+        end
+
+        # Traversal of ObjectSpace is expensive, on fully loaded application
+        # it takes around 80ms. The instances of HttpServers are not a subject
+        # to change so we can cache the list of servers.
+        def http_servers
+          strong_memoize(:http_servers) do
+            next unless defined?(::Unicorn::HttpServer)
+
+            ObjectSpace.each_object(::Unicorn::HttpServer).to_a
+          end
+        end
+      end
+    end
+  end
+end