Allow `rake cache:clear` clearing pipeline status cache44582-clear-pipeline-status-cache

* Use the correct key prefix
* Clear old cache keys

TODO:

At some point we could remove clearing old cache keys.

5 files changed, 40 insertions, 11 deletions

diff --git a/changelogs/unreleased/44582-clear-pipeline-status-cache.yml b/changelogs/unreleased/44582-clear-pipeline-status-cache.yml
new file mode 100644
index 00000000000..1777f2ffaab
--- /dev/null
+++ b/changelogs/unreleased/44582-clear-pipeline-status-cache.yml
@@ -0,0 +1,5 @@
+---
+title: Now `rake cache:clear` will also clear pipeline status cache
+merge_request: 18257
+author:
+type: fixed
diff --git a/lib/gitlab/cache/ci/project_pipeline_status.rb b/lib/gitlab/cache/ci/project_pipeline_status.rb
index dba37892863..add048d671e 100644
--- a/lib/gitlab/cache/ci/project_pipeline_status.rb
+++ b/lib/gitlab/cache/ci/project_pipeline_status.rb
@@ -40,7 +40,7 @@ module Gitlab
         end
 
         def self.cache_key_for_project(project)
-          "projects/#{project.id}/pipeline_status"
+          "#{Gitlab::Redis::Cache::CACHE_NAMESPACE}:projects/#{project.id}/pipeline_status"
         end
 
         def self.update_for_pipeline(pipeline)
diff --git a/lib/tasks/cache.rake b/lib/tasks/cache.rake
index 564aa141952..cb4d5abffbc 100644
--- a/lib/tasks/cache.rake
+++ b/lib/tasks/cache.rake
@@ -6,17 +6,22 @@ namespace :cache do
     desc "GitLab | Clear redis cache"
     task redis: :environment do
       Gitlab::Redis::Cache.with do |redis|
-        cursor = REDIS_SCAN_START_STOP
-        loop do
-          cursor, keys = redis.scan(
-            cursor,
-            match: "#{Gitlab::Redis::Cache::CACHE_NAMESPACE}*",
-            count: REDIS_CLEAR_BATCH_SIZE
-          )
+        cache_key_pattern = %W[#{Gitlab::Redis::Cache::CACHE_NAMESPACE}*
+                               projects/*/pipeline_status]
 
-          redis.del(*keys) if keys.any?
+        cache_key_pattern.each do |match|
+          cursor = REDIS_SCAN_START_STOP
+          loop do
+            cursor, keys = redis.scan(
+              cursor,
+              match: match,
+              count: REDIS_CLEAR_BATCH_SIZE
+            )
 
-          break if cursor == REDIS_SCAN_START_STOP
+            redis.del(*keys) if keys.any?
+
+            break if cursor == REDIS_SCAN_START_STOP
+          end
         end
       end
     end
diff --git a/spec/lib/gitlab/cache/ci/project_pipeline_status_spec.rb b/spec/lib/gitlab/cache/ci/project_pipeline_status_spec.rb
index 16704ff5e77..18658588a40 100644
--- a/spec/lib/gitlab/cache/ci/project_pipeline_status_spec.rb
+++ b/spec/lib/gitlab/cache/ci/project_pipeline_status_spec.rb
@@ -3,7 +3,7 @@ require 'spec_helper'
 describe Gitlab::Cache::Ci::ProjectPipelineStatus, :clean_gitlab_redis_cache do
   let!(:project) { create(:project, :repository) }
   let(:pipeline_status) { described_class.new(project) }
-  let(:cache_key) { "projects/#{project.id}/pipeline_status" }
+  let(:cache_key) { described_class.cache_key_for_project(project) }
 
   describe '.load_for_project' do
     it "loads the status" do
diff --git a/spec/tasks/cache/clear/redis_spec.rb b/spec/tasks/cache/clear/redis_spec.rb
new file mode 100644
index 00000000000..cca2b864e9b
--- /dev/null
+++ b/spec/tasks/cache/clear/redis_spec.rb
@@ -0,0 +1,19 @@
+require 'rake_helper'
+
+describe 'clearing redis cache' do
+  before do
+    Rake.application.rake_require 'tasks/cache'
+  end
+
+  describe 'clearing pipeline status cache' do
+    let(:pipeline_status) { create(:ci_pipeline).project.pipeline_status }
+
+    before do
+      allow(pipeline_status).to receive(:loaded).and_return(nil)
+    end
+
+    it 'clears pipeline status cache' do
+      expect { run_rake_task('cache:clear:redis') }.to change { pipeline_status.has_cache? }
+    end
+  end
+end