Expire Ci::Minutes::CachedQuota when minutes limits are updated

- When quota is reset by admin
- when monthly limit is updated via API (plan change)
- when additional minutes limit is updated via API (purchases)

ee/app/services/clear_namespace_shared_runners_minutes_service.rb

@@ -10,7 +10,9 @@ class ClearNamespaceSharedRunnersMinutesService < BaseService
     NamespaceStatistics.where(namespace: @namespace).update_all(
       shared_runners_seconds: 0,
       shared_runners_seconds_last_reset: Time.current
-    )
+    ).tap do
+      ::Gitlab::Ci::Minutes::CachedQuota.new(@namespace).expire!
+    end
   end
   # rubocop: enable CodeReuse/ActiveRecord
 end

ee/lib/ee/api/namespaces.rb

@@ -29,6 +29,10 @@ module EE
               ::Ci::Runner.instance_type.each(&:tick_runner_queue)
             end
 
+            if params[:extra_shared_runners_minutes_limit].present? || params[:shared_runners_minutes_limit].present?
+              ::Gitlab::Ci::Minutes::CachedQuota.new(namespace).expire!
+            end
+
             namespace.update(update_attrs)
           end
         end

ee/lib/gitlab/ci/minutes/cached_quota.rb

@@ -16,12 +16,10 @@ module Gitlab
           @root_namespace = root_namespace
         end
 
-        # TODO:
-        #   - when monthly minutes are updated via the API (e.g. plan change)
-        #   - when extra_shared_runners_minutes_limit are updated via the API
-        #   - when minutes consumption is reset via the controller (TS or admin)
         def expire!
-          # todo
+          ::Gitlab::Redis::SharedState.with do |redis|
+            redis.unlink(cache_key)
+          end
         end
 
         # Reduces the remaining minutes by the consumption argument.

ee/spec/lib/gitlab/ci/minutes/cached_quota_spec.rb

@@ -46,4 +46,22 @@ RSpec.describe Gitlab::Ci::Minutes::CachedQuota do
       end
     end
   end
+
+  describe '#expire!' do
+    subject { cached_quota.expire! }
+
+    before do
+      ::Gitlab::Redis::SharedState.with do |redis|
+        redis.set(cached_quota.cache_key, 80.0, ex: 20)
+      end
+    end
+
+    it 'expires the key' do
+      subject
+
+      ::Gitlab::Redis::SharedState.with do |redis|
+        expect(redis.exists(cached_quota.cache_key)).to be_falsey
+      end
+    end
+  end
 end

ee/spec/requests/api/namespaces_spec.rb

@@ -3,6 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe API::Namespaces do
+  include AfterNextHelpers
+
   let(:admin) { create(:admin) }
   let(:user) { create(:user) }
 
@@ -218,6 +220,34 @@ RSpec.describe API::Namespaces do
         expect(json_response['additional_purchased_storage_size']).to eq(params[:additional_purchased_storage_size])
         expect(json_response['additional_purchased_storage_ends_on']).to eq(params[:additional_purchased_storage_ends_on])
       end
+
+      it 'expires the CI minutes CachedQuota' do
+        expect_next(Gitlab::Ci::Minutes::CachedQuota).to receive(:expire!)
+
+        put api("/namespaces/#{group1.id}", admin), params: params
+      end
+
+      context 'when request has extra_shared_runners_minutes_limit param' do
+        before do
+          params[:extra_shared_runners_minutes_limit] = 1000
+          params.delete(:shared_runners_minutes_limit)
+        end
+
+        it 'expires the CI minutes CachedQuota' do
+          expect_next(Gitlab::Ci::Minutes::CachedQuota).to receive(:expire!)
+
+          put api("/namespaces/#{group1.id}", admin), params: params
+        end
+      end
+
+      context 'when neither minutes limit params is provided' do
+        it 'does not expire the CI minutes CachedQuota' do
+          params.delete(:shared_runners_minutes_limit)
+          expect(Gitlab::Ci::Minutes::CachedQuota).not_to receive(:new)
+
+          put api("/namespaces/#{group1.id}", admin), params: params
+        end
+      end
     end
 
     context 'when not authenticated as admin' do

ee/spec/services/clear_namespace_shared_runners_minutes_service_spec.rb

@@ -3,6 +3,8 @@
 require 'spec_helper'
 
 RSpec.describe ClearNamespaceSharedRunnersMinutesService do
+  include AfterNextHelpers
+
   describe '#execute' do
     subject { described_class.new(namespace).execute }
 
@@ -24,6 +26,12 @@ RSpec.describe ClearNamespaceSharedRunnersMinutesService do
       it 'successfully clears minutes' do
         expect(subject).to be_truthy
       end
+
+      it 'expires the CachedQuota' do
+        expect_next(Gitlab::Ci::Minutes::CachedQuota).to receive(:expire!)
+
+        subject
+      end
     end
 
     context 'when project does not have namespace_statistics' do