(SUP-2404) Migrate from cron to systemd units

Prior to this commit, maintenance and backups were done with cron
entries.  This commit replaces all but the backup feature with systemd
services and timers to provide better logging.

Author: m0dular

.sync.yml

@@ -34,18 +34,11 @@ spec/spec_helper.rb:
   coverage_report: true
 spec/default_facts.yml:
   extra_facts:
-    pe_server_version: 2018.1.0
-    memory:
-      "system":
-        "total": "16.00 GiB"
-        "total_bytes": 17179869184
-    processors:
-      "count": 8
-spec/default_facts.yml:
-  extra_facts:
+    pe_databases:
+      have_systemd: true
     pe_postgresql_info:
-      installed_server_version: 9.6
-    pe_server_version: 2018.1.0
+      installed_server_version: 11
+    pe_server_version: 2019.8.6
     memory:
       system:
         total: 16.00 GiB

files/vacuum_full_tables.sh

@@ -0,0 +1,11 @@
+Facter.add(:pe_databases, type: :aggregate) do
+  confine kernel: 'Linux'
+
+  chunk(:have_systemd) do
+    if Puppet::FileSystem.exist?('/proc/1/comm') && Puppet::FileSystem.read('/proc/1/comm').include?('systemd')
+      { have_systemd: true }
+    else
+      { have_systemd: false }
+    end
+  end
+end

lib/facter/pe_databases.rb

@@ -0,0 +1,41 @@
+# Create systemd units for repacking a given database type
+define pe_databases::collect (
+  String  $database_type       = $title,
+  String  $command             = undef,
+  Boolean $disable_maintenance = false,
+  String  $on_cal              = undef,
+) {
+
+  Service {
+    notify  => Exec['pe_databases_daemon_reload'],
+  }
+  File {
+    notify  => Exec['pe_databases_daemon_reload'],
+  }
+
+  $ensure_service = $disable_maintenance ? {
+    true  => stopped,
+    default => running,
+  }
+
+  $ensure_file = $disable_maintenance ? {
+    true    => absent,
+    default => present
+  }
+
+  file {"/etc/systemd/system/pe_databases-${database_type}.service":
+    ensure  => $ensure_file,
+    content => epp('pe_databases/service.epp', { 'tables' => $database_type, 'command' => $command }),
+  }
+  file {"/etc/systemd/system/pe_databases-${database_type}.timer":
+    ensure  => $ensure_file,
+    content => epp('pe_databases/timer.epp', { 'tables' => $database_type, 'on_cal' => $on_cal }),
+  }
+
+  service { "pe_databases-${database_type}.service": }
+  service { "pe_databases-${database_type}.timer":
+    ensure    => $ensure_service,
+    enable    => ! $disable_maintenance,
+    subscribe => File["/etc/systemd/system/pe_databases-${database_type}.timer"],
+  }
+}

manifests/collect.pp

@@ -3,7 +3,7 @@
 # @summary Tuning, maintenance, and backups for PE PostgreSQL.
 
 class pe_databases (
-  Boolean $manage_database_backups     = true,
+  Boolean $manage_database_backups     = false,
   Boolean $manage_database_maintenance = true,
   Boolean $manage_postgresql_settings  = true,
   Boolean $manage_table_settings       = true,
@@ -21,27 +21,39 @@
     mode   => '0755',
   }
 
-  if $manage_database_maintenance {
-    include pe_databases::maintenance
+  exec { 'pe_databases_daemon_reload':
+    command     => 'systemctl daemon-reload',
+    path        => ['/bin', '/usr/bin'],
+    refreshonly => true,
   }
 
-  # Do not manage postgresql_settings in 2018.1.0 or newer.
-  if $manage_postgresql_settings and (versioncmp('2018.1.0', $facts['pe_server_version']) > 0) {
-    include pe_databases::postgresql_settings
-    class { 'pe_databases::postgresql_settings::table_settings' :
-      manage_reports_autovacuum_cost_delay    => $pe_databases::postgresql_settings::manage_reports_autovacuum_cost_delay,
-      factsets_autovacuum_vacuum_scale_factor => $pe_databases::postgresql_settings::factsets_autovacuum_vacuum_scale_factor,
-      reports_autovacuum_vacuum_scale_factor  => $pe_databases::postgresql_settings::reports_autovacuum_vacuum_scale_factor,
-      require                                 => Class['pe_databases::postgresql_settings'],
+  if $facts.dig('pe_databases', 'have_systemd') {
+    if $manage_database_maintenance and (versioncmp('2019.0.2', $facts['pe_server_version']) <= 0) {
+      class {'pe_databases::pg_repack':
+        disable_maintenance => lookup('pe_databases::maintenance::disable_maintenance', {'default_value' => false}),
+      }
+      if $manage_table_settings {
+        # This is to provide for situations, like PE XL,
+        # where the pe-puppetdb database does not exist on the PostgreSQL system being tuned.
+        # In PE XL, the Master and Replica run PostgreSQL for all databases *except* for pe-puppetdb.
+        include pe_databases::postgresql_settings::table_settings
+      }
+
+      if $manage_database_backups {
+        include pe_databases::backup
+      }
+    }
+    else {
+      notify { 'pe_databases_version_warn':
+        message  => 'This module only supports PE 2019.0.2 and later',
+        loglevel => warning,
+      }
     }
-  } elsif $manage_table_settings {
-    # This is to provide for situations, like PE XL,
-    # where the pe-puppetdb database does not exist on the PostgreSQL system being tuned.
-    # In PE XL, the Master and Replica run PostgreSQL for all databases *except* for pe-puppetdb.
-    include pe_databases::postgresql_settings::table_settings
   }
-
-  if $manage_database_backups {
-    include pe_databases::backup
+  else {
+    notify { 'pe_databases_systemd_warn':
+      message  => 'This module only works with systemd as the provider',
+      loglevel => warning,
+    }
   }
 }