Use state machine for pipeline event processing

3 files changed, 50 insertions, 24 deletions

diff --git a/app/models/ci/pipeline.rb b/app/models/ci/pipeline.rb
index 8de799d6088..7a0430f277a 100644
--- a/app/models/ci/pipeline.rb
+++ b/app/models/ci/pipeline.rb
@@ -19,6 +19,37 @@ module Ci
 
     after_save :keep_around_commits
 
+    state_machine :status, initial: :created do
+      event :skip do
+        transition any => :skipped
+      end
+
+      event :drop do
+        transition any => :failed
+      end
+
+      event :update_status do
+        transition any => :pending, if: ->(pipeline) { pipeline.can_transition_to?('pending') }
+        transition any => :running, if: ->(pipeline) { pipeline.can_transition_to?('running') }
+        transition any => :failed, if: ->(pipeline) { pipeline.can_transition_to?('failed') }
+        transition any => :success, if: ->(pipeline) { pipeline.can_transition_to?('success') }
+        transition any => :canceled, if: ->(pipeline) { pipeline.can_transition_to?('canceled') }
+        transition any => :skipped, if: ->(pipeline) { pipeline.can_transition_to?('skipped') }
+      end
+
+      after_transition [:created, :pending] => :running do |pipeline|
+        pipeline.update(started_at: Time.now)
+      end
+
+      after_transition any => [:success, :failed, :canceled] do |pipeline|
+        pipeline.update(finished_at: Time.now)
+      end
+
+      after_transition do |pipeline|
+        pipeline.update_duration
+      end
+    end
+
     # ref can't be HEAD or SHA, can only be branch/tag name
     scope :latest_successful_for, ->(ref = default_branch) do
       where(ref: ref).success.order(id: :desc).limit(1)
@@ -89,16 +120,12 @@ module Ci
 
     def cancel_running
       builds.running_or_pending.each(&:cancel)
-
-      reload_status!
     end
 
     def retry_failed(user)
       builds.latest.failed.select(&:retryable?).each do |build|
         Ci::Build.retry(build, user)
       end
-
-      reload_status!
     end
 
     def latest?
@@ -185,8 +212,6 @@ module Ci
 
     def process!
       Ci::ProcessPipelineService.new(project, user).execute(self)
-
-      reload_status!
     end
 
     def predefined_variables
@@ -195,22 +220,22 @@ module Ci
       ]
     end
 
-    def reload_status!
-      reload
-      self.status =
-        if yaml_errors.blank?
-          statuses.latest.status || 'skipped'
-        else
-          'failed'
-        end
-      self.started_at = statuses.started_at
-      self.finished_at = statuses.finished_at
-      self.duration = statuses.latest.duration
-      save
+    def can_transition_to?(expected_status)
+      latest_status == expected_status
+    end
+
+    def update_duration
+      update(duration: statuses.latest.duration)
     end
 
     private
 
+    def latest_status
+      return 'failed' unless yaml_errors.blank?
+
+      statuses.latest.status || 'skipped'
+    end
+
     def keep_around_commits
       return unless project
 
diff --git a/app/models/commit_status.rb b/app/models/commit_status.rb
index 3ab44461179..64ce5431d63 100644
--- a/app/models/commit_status.rb
+++ b/app/models/commit_status.rb
@@ -74,13 +74,13 @@ class CommitStatus < ActiveRecord::Base
     around_transition any => [:success, :failed, :canceled] do |commit_status, block|
       block.call
 
-      commit_status.pipeline.process! if commit_status.pipeline
+      commit_status.pipeline.try(:process!)
     end
 
-    around_transition any => [:pending, :running] do |commit_status, block|
-      block.call
+    # Try to update the pipeline status
 
-      commit_status.pipeline.reload_status! if commit_status.pipeline
+    after_transition do |commit_status, transition|
+      commit_status.pipeline.try(:update_status) unless transition.loopback?
     end
   end
 
diff --git a/app/services/ci/create_pipeline_service.rb b/app/services/ci/create_pipeline_service.rb
index 7398fd8e10a..cde856b0186 100644
--- a/app/services/ci/create_pipeline_service.rb
+++ b/app/services/ci/create_pipeline_service.rb
@@ -37,7 +37,8 @@ module Ci
       end
 
       if !ignore_skip_ci && skip_ci?
-        return error('Creation of pipeline is skipped', save: save_on_errors)
+        pipeline.skip if save_on_errors
+        return pipeline
       end
 
       unless pipeline.config_builds_attributes.present?
@@ -93,7 +94,7 @@ module Ci
 
     def error(message, save: false)
       pipeline.errors.add(:base, message)
-      pipeline.reload_status! if save
+      pipeline.drop if save
       pipeline
     end
   end