From 830198b75c1fc75791187455f7976f0a87493ef7 Mon Sep 17 00:00:00 2001
From: Kamil Trzcinski <ayufan@ayufan.eu>
Date: Tue, 21 Mar 2017 13:58:31 +0100
Subject: Improve resiliency of build picking

Every time we pick a new build, or we get into conflict we force runner to retry the operation to make sure that all builds are being picked.

It makes us to loose one request, but also makes sure that we are consistent.

It is fair trade, as number of generated builds is relatively small 0.1% compared to the traffic.
---
 lib/ci/api/builds.rb  | 29 +++++++++++++++++++----------
 lib/ci/api/helpers.rb |  8 ++++++++
 2 files changed, 27 insertions(+), 10 deletions(-)

(limited to 'lib/ci/api')

diff --git a/lib/ci/api/builds.rb b/lib/ci/api/builds.rb
index 746e76a1b1f..f39b509873c 100644
--- a/lib/ci/api/builds.rb
+++ b/lib/ci/api/builds.rb
@@ -13,35 +13,44 @@ module Ci
         post "register" do
           authenticate_runner!
           required_attributes! [:token]
-          not_found! unless current_runner.active?
           update_runner_info
 
           if current_runner.is_runner_queue_value_latest?(params[:last_update])
-            header 'X-GitLab-Last-Update', params[:last_update]
-            Gitlab::Metrics.add_event(:build_not_found_cached)
+            Gitlab::Metrics.add_event(:build_not_found_cached,
+              version: get_runner_version)
+            header_last_update(params[:last_update])
             return build_not_found!
           end
 
           new_update = current_runner.ensure_runner_queue_value
 
+          unless current_runner.active?
+            Gitlab::Metrics.add_event(:runner_inactive,
+              version: get_runner_version)
+            header_last_update(new_update)
+            return build_not_found!
+          end
+
           result = Ci::RegisterJobService.new(current_runner).execute
 
           if result.valid?
             if result.build
               Gitlab::Metrics.add_event(:build_found,
-                                        project: result.build.project.path_with_namespace)
-
+                project: result.build.project.path_with_namespace,
+                version: get_runner_version)
+              header_last_update(current_runner.tick_runner_queue_value)
               present result.build, with: Entities::BuildDetails
             else
-              Gitlab::Metrics.add_event(:build_not_found)
-
-              header 'X-GitLab-Last-Update', new_update
-
+              Gitlab::Metrics.add_event(:build_not_found,
+                version: get_runner_version)
+              header_last_update(new_update)
               build_not_found!
             end
           else
             # We received build that is invalid due to concurrency conflict
-            Gitlab::Metrics.add_event(:build_invalid)
+            Gitlab::Metrics.add_event(:build_invalid,
+              version: get_runner_version)
+            header_last_update(current_runner.tick_runner_queue_value)
             conflict!
           end
         end
diff --git a/lib/ci/api/helpers.rb b/lib/ci/api/helpers.rb
index 996990b464f..868a9cdec70 100644
--- a/lib/ci/api/helpers.rb
+++ b/lib/ci/api/helpers.rb
@@ -79,6 +79,14 @@ module Ci
       def max_artifacts_size
         current_application_settings.max_artifacts_size.megabytes.to_i
       end
+
+      def get_runner_version
+        params.fetch('info', {}).fetch('version', "unknown")
+      end
+
+      def header_last_update(value)
+        header 'X-GitLab-Last-Update', value
+      end
     end
   end
 end
-- 
cgit v1.2.1