(PE-38814) add_compiler - Making primary_postgresql_host and avail_gr…

…oup_letter optional

primary_postgresql_host, if not provided will be determined through get_peadm_config
avail_group_letter, is defaulting to A

REFERENCE.md

@@ -1571,10 +1571,12 @@ The following parameters are available in the `peadm::add_compiler` plan:
 
 ##### <a name="-peadm--add_compiler--avail_group_letter"></a>`avail_group_letter`
 
-Data type: `Enum['A', 'B']`
+Data type: `Optional[Enum['A', 'B']]`
 
 _ Either A or B; whichever of the two letter designations the compiler is being assigned to
 
+Default value: `'A'`
+
 ##### <a name="-peadm--add_compiler--compiler_host"></a>`compiler_host`
 
 Data type: `Peadm::SingleTargetSpec`
@@ -1597,10 +1599,12 @@ _ The hostname and certname of the primary Puppet server
 
 ##### <a name="-peadm--add_compiler--primary_postgresql_host"></a>`primary_postgresql_host`
 
-Data type: `Peadm::SingleTargetSpec`
+Data type: `Optional[Peadm::SingleTargetSpec]`
 
 _ The hostname and certname of the PE-PostgreSQL server with availability group $avail_group_letter
 
+Default value: `undef`
+
 ### <a name="peadm--add_database"></a>`peadm::add_database`
 
 The peadm::add_database class.

plans/add_compiler.pp

@@ -7,20 +7,37 @@
 # @param primary_host _ The hostname and certname of the primary Puppet server
 # @param primary_postgresql_host _ The hostname and certname of the PE-PostgreSQL server with availability group $avail_group_letter
 plan peadm::add_compiler(
-  Enum['A', 'B'] $avail_group_letter,
+  Optional[Enum['A', 'B']] $avail_group_letter = 'A' ,
   Optional[String[1]] $dns_alt_names = undef,
   Peadm::SingleTargetSpec $compiler_host,
   Peadm::SingleTargetSpec $primary_host,
-  Peadm::SingleTargetSpec $primary_postgresql_host,
+  Optional[Peadm::SingleTargetSpec] $primary_postgresql_host = undef,
 ) {
   $compiler_target           = peadm::get_targets($compiler_host, 1)
   $primary_target            = peadm::get_targets($primary_host, 1)
-  $primary_postgresql_target = peadm::get_targets($primary_postgresql_host, 1)
 
   # Get current peadm config to determine where to setup additional rules for
   # compiler's secondary PuppetDB instances
   $peadm_config = run_task('peadm::get_peadm_config', $primary_target).first.value
 
+  if $primary_postgresql_host == undef {
+    # get the external PostgreSQL host for the specified availability group
+    $external_postgresql_host = $avail_group_letter ? {
+      'A'     => $peadm_config['params']['primary_postgresql_host'],
+      default => $peadm_config['params']['replica_postgresql_host'],
+    }
+
+    # If the external_postgresql_host is undef, use the server for that availability group
+    $postgresql_host = $external_postgresql_host ? {
+      undef   => $peadm_config['role-letter']['server'][$avail_group_letter],
+      default => $external_postgresql_host,
+    }
+
+    $primary_postgresql_target = peadm::get_targets($postgresql_host, 1)
+  } else {
+    $primary_postgresql_target = peadm::get_targets($primary_postgresql_host, 1)
+  }
+
   # Return the opposite server than the compiler to be added so it can be
   # configured with the appropriate rules for Puppet Server access from
   # compiler