Add support for cron job to purge objects

watcher provides the CLI tool to purge delete or orphaned objects from
database[1]. This allows users to set up cron job to periodically
execute the CLI to reduce database size.

[1] https://docs.openstack.org/watcher/latest/man/watcher-db-manage.html#purge

Change-Id: I70fe945818fdd4a31ddd0d0d502df53f6eeb5b3f

manifests/cron/db_purge.pp

@@ -0,0 +1,116 @@
+#
+# Copyright (C) 2023 Red Hat Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+# == Class: watcher::cron::db_purge
+#
+# Purge soft-deleted or orphaned records from database.
+#
+# === Parameters
+#
+#  [*ensure*]
+#    (optional) Ensure cron jobs present or absent
+#    Defaults to present.
+#
+#  [*minute*]
+#    (optional) Defaults to '1'.
+#
+#  [*hour*]
+#    (optional) Defaults to '0'.
+#
+#  [*monthday*]
+#    (optional) Defaults to '*'.
+#
+#  [*month*]
+#    (optional) Defaults to '*'.
+#
+#  [*weekday*]
+#    (optional) Defaults to '*'.
+#
+#  [*user*]
+#    (optional) User with access to watcher files.
+#    Defaults to 'watcher'.
+#
+#  [*age*]
+#    (optional) Number of days prior to today for deletion,
+#    e.g. value 60 means to purge deleted rows that have the "deleted_at"
+#    column greater than 60 days ago.
+#    Defaults to 30
+#
+#  [*destination*]
+#    (optional) Path to file to which rows should be archived
+#    Defaults to '/var/log/watcher/watcher-rowsflush.log'.
+#
+#  [*maxdelay*]
+#    (optional) In Seconds. Should be a positive integer.
+#    Induces a random delay before running the cronjob to avoid running
+#    all cron jobs at the same time on all hosts this job is configured.
+#    Defaults to 0.
+#
+#  [*exclude_orphans*]
+#    (optional) Flag to indicate whether orhans should be excluded from
+#    deletion.
+#    Defaults to false
+#
+#  [*max_number*]
+#    (optional) Max number of objects expected to be deleted.
+#    Defaults to undef
+#
+class watcher::cron::db_purge (
+  Enum['present', 'absent'] $ensure = 'present',
+  $minute          = 1,
+  $hour            = 0,
+  $monthday        = '*',
+  $month           = '*',
+  $weekday         = '*',
+  $user            = $::watcher::params::user,
+  $age             = 30,
+  $destination     = '/var/log/watcher/watcher-rowsflush.log',
+  $maxdelay        = 0,
+  $exclude_orphans = false,
+  $max_number      = undef,
+) inherits watcher::params {
+
+  validate_legacy(Boolean, 'validate_bool', $exclude_orphans)
+
+  include watcher::deps
+
+  $sleep = $maxdelay ? {
+    0       => '',
+    default => "sleep `expr \${RANDOM} \\% ${maxdelay}`; ",
+  }
+
+  $exclude_orphans_opt = $exclude_orphans ? {
+    true    => ' -e',
+    default => '',
+  }
+
+  $max_number_opt =  $max_number ? {
+    undef   => '',
+    default => " -n ${max_number}",
+  }
+
+  cron { 'watcher-db-manage purge':
+    ensure      => $ensure,
+    command     => "${sleep}watcher-db-manage purge -d ${age}${exclude_orphans_opt}${max_number_opt} >>${destination} 2>&1",
+    environment => 'PATH=/bin:/usr/bin:/usr/sbin SHELL=/bin/sh',
+    user        => $user,
+    minute      => $minute,
+    hour        => $hour,
+    monthday    => $monthday,
+    month       => $month,
+    weekday     => $weekday,
+    require     => Anchor['watcher::db::upgrade::end'],
+  }
+}

releasenotes/notes/cron-db_purge-43ea67b564185d97.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    The new ``watcher::cron::db_purge`` class has been added. This class can be
+    used to configure cron job to periodically purge deleted or orphaned
+    objects from database.

spec/classes/watcher_cron_db_purge_spec.rb

@@ -0,0 +1,99 @@
+require 'spec_helper'
+
+describe 'watcher::cron::db_purge' do
+  let :params do
+    {
+      :minute      => 1,
+      :hour        => 0,
+      :monthday    => '*',
+      :month       => '*',
+      :weekday     => '*',
+      :user        => 'watcher',
+      :age         => '30',
+      :maxdelay    => 0,
+      :destination => '/var/log/watcher/watcher-rowsflush.log'
+    }
+  end
+
+  shared_examples 'watcher::cron::db_purge' do
+    context 'with required parameters' do
+      it { is_expected.to contain_cron('watcher-db-manage purge').with(
+        :ensure      => :present,
+        :command     => "watcher-db-manage purge -d #{params[:age]} >>#{params[:destination]} 2>&1",
+        :environment => 'PATH=/bin:/usr/bin:/usr/sbin SHELL=/bin/sh',
+        :user        => params[:user],
+        :minute      => params[:minute],
+        :hour        => params[:hour],
+        :monthday    => params[:monthday],
+        :month       => params[:month],
+        :weekday     => params[:weekday],
+        :require     => 'Anchor[watcher::db::upgrade::end]'
+      )}
+    end
+
+    context 'with ensure set to absent' do
+      before :each do
+        params.merge!(
+          :ensure => :absent
+        )
+      end
+
+      it { should contain_cron('watcher-db-manage purge').with_ensure(:absent) }
+    end
+
+    context 'with required parameters with max delay enabled' do
+      before :each do
+        params.merge!(
+          :maxdelay => 600
+        )
+      end
+
+      it { should contain_cron('watcher-db-manage purge').with(
+        :ensure      => :present,
+        :command     => "sleep `expr ${RANDOM} \\% #{params[:maxdelay]}`; watcher-db-manage purge -d #{params[:age]} >>#{params[:destination]} 2>&1",
+        :environment => 'PATH=/bin:/usr/bin:/usr/sbin SHELL=/bin/sh',
+        :user        => params[:user],
+        :minute      => params[:minute],
+        :hour        => params[:hour],
+        :monthday    => params[:monthday],
+        :month       => params[:month],
+        :weekday     => params[:weekday],
+        :require     => 'Anchor[watcher::db::upgrade::end]'
+      )}
+    end
+
+    context 'with additional parameters' do
+      before :each do
+        params.merge!(
+          :exclude_orphans => true,
+          :max_number      => 100,
+        )
+      end
+
+      it { should contain_cron('watcher-db-manage purge').with(
+        :ensure      => :present,
+        :command     => "watcher-db-manage purge -d #{params[:age]} -e -n #{params[:max_number]} >>#{params[:destination]} 2>&1",
+        :environment => 'PATH=/bin:/usr/bin:/usr/sbin SHELL=/bin/sh',
+        :user        => params[:user],
+        :minute      => params[:minute],
+        :hour        => params[:hour],
+        :monthday    => params[:monthday],
+        :month       => params[:month],
+        :weekday     => params[:weekday],
+        :require     => 'Anchor[watcher::db::upgrade::end]'
+      )}
+    end
+  end
+
+  on_supported_os({
+    :supported_os => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
+
+      it_behaves_like 'watcher::cron::db_purge'
+    end
+  end
+end