Partition pruning for the web_hook_logs table

Detach and drop database partitions for the web_hook_logs table that are
over 3 months old to delete unneeded data and save space

Changelog: added

config/feature_flags/development/drop_detached_partitions.yml

----
-name: drop_detached_partitions
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/67056
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/337155
-milestone: '14.2'
-type: development
-group: group::database
-default_enabled: false

config/feature_flags/development/partition_pruning.yml

----
-name: partition_pruning
-introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/67056
-rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/337153
-milestone: '14.2'
-type: development
-group: group::database
-default_enabled: false

lib/gitlab/database/partitioning/detached_partition_dropper.rb

@@ -4,8 +4,6 @@ module Gitlab
     module Partitioning
       class DetachedPartitionDropper
         def perform
-          return unless Feature.enabled?(:drop_detached_partitions, default_enabled: :yaml)
-
           Gitlab::AppLogger.info(message: "Checking for previously detached partitions to drop")
 
           Postgresql::DetachedPartition.ready_to_drop.find_each do |detached_partition|

lib/gitlab/database/partitioning/partition_manager.rb

@@ -25,10 +25,8 @@ module Gitlab
             partitions_to_create = missing_partitions
             create(partitions_to_create) unless partitions_to_create.empty?
 
-            if Feature.enabled?(:partition_pruning, default_enabled: :yaml)
-              partitions_to_detach = extra_partitions
-              detach(partitions_to_detach) unless partitions_to_detach.empty?
-            end
+            partitions_to_detach = extra_partitions
+            detach(partitions_to_detach) unless partitions_to_detach.empty?
           end
         rescue StandardError => e
           Gitlab::AppLogger.error(message: "Failed to create / detach partition(s)",

spec/lib/gitlab/database/partitioning/detached_partition_dropper_spec.rb

@@ -90,18 +90,6 @@ RSpec.describe Gitlab::Database::Partitioning::DetachedPartitionDropper do
         expect(table_oid('test_partition')).to be_nil
       end
 
-      context 'when the drop_detached_partitions feature flag is disabled' do
-        before do
-          stub_feature_flags(drop_detached_partitions: false)
-        end
-
-        it 'does not drop the partition' do
-          dropper.perform
-
-          expect(table_oid('test_partition')).not_to be_nil
-        end
-      end
-
       context 'removing foreign keys' do
         it 'removes foreign keys from the table before dropping it' do
           expect(dropper).to receive(:drop_detached_partition).and_wrap_original do |drop_method, partition_name|

spec/lib/gitlab/database/partitioning/partition_manager_spec.rb

@@ -101,28 +101,10 @@ RSpec.describe Gitlab::Database::Partitioning::PartitionManager do
       ]
     end
 
-    context 'with the partition_pruning feature flag enabled' do
-      before do
-        stub_feature_flags(partition_pruning: true)
-      end
-
-      it 'detaches each extra partition' do
-        extra_partitions.each { |p| expect(manager).to receive(:detach_one_partition).with(p) }
-
-        sync_partitions
-      end
-    end
+    it 'detaches each extra partition' do
+      extra_partitions.each { |p| expect(manager).to receive(:detach_one_partition).with(p) }
 
-    context 'with the partition_pruning feature flag disabled' do
-      before do
-        stub_feature_flags(partition_pruning: false)
-      end
-
-      it 'returns immediately' do
-        expect(manager).not_to receive(:detach)
-
-        sync_partitions
-      end
+      sync_partitions
     end
   end