From b66218dc10a57f850b59b47670189df7005c6351 Mon Sep 17 00:00:00 2001
From: Samuel Beaulieu <samuel+14401380@puppet.com>
Date: Fri, 31 Dec 2021 09:35:29 -0600
Subject: [PATCH] replace dns zone entry if it already exists on the rare
 occasion where adding a dns record and we get teh error it already exists
 assume that it is stale and replace it with the new IP

---
 lib/vmpooler/providers/gce.rb | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/lib/vmpooler/providers/gce.rb b/lib/vmpooler/providers/gce.rb
index 3381471..3da189f 100644
--- a/lib/vmpooler/providers/gce.rb
+++ b/lib/vmpooler/providers/gce.rb
@@ -134,7 +134,7 @@ module Vmpooler
         #    [String] hostname   : Specifies the hostname of the instance. The specified hostname must be RFC1035 compliant. If hostname is not specified,
         #                          the default hostname is [ INSTANCE_NAME].c.[PROJECT_ID].internal when using the global DNS, and
         #                          [ INSTANCE_NAME].[ZONE].c.[PROJECT_ID].internal when using zonal DNS
-        #    [String] template   : This is the name of template exposed by the API.  It must _match_ the poolname ??? TODO
+        #    [String] template   : This is the name of template
         #    [String] poolname   : Name of the pool the VM as per labels
         #    [Time]   boottime   : Time when the VM was created/booted
         #    [String] status     : One of the following values: PROVISIONING, STAGING, RUNNING, STOPPING, SUSPENDING, SUSPENDED, REPAIRING, and TERMINATED
@@ -198,9 +198,6 @@ module Vmpooler
             network_interfaces: [network_interfaces],
             labels: { 'vm' => new_vmname, 'pool' => pool_name, project => nil }
           )
-          # TODO: Maybe this will be needed to set the hostname (usually internal DNS name but in our case for some reason its nil)
-          # given_hostname = "#{new_vmname}.#{dns_zone}"
-          # client.hostname = given_hostname if given_hostname
 
           debug_logger('trigger insert_instance')
           result = connection.insert_instance(project, zone(pool_name), client)
@@ -559,14 +556,17 @@ module Vmpooler
 
         def dns_setup(created_instance)
           zone = dns.zone dns_zone_resource_name if dns_zone_resource_name
-          return unless zone && created_instance
+          return unless zone && created_instance && created_instance['name'] && created_instance['ip']
 
           name = created_instance['name']
-          change = zone.add name, 'A', 60, [created_instance['ip']]
-          debug_logger("#{change.id} - #{change.started_at} - #{change.status}") if change
-          # TODO: should we catch Google::Cloud::AlreadyExistsError that is thrown when it already exist?
-          # and then delete and recreate?
-          # eg the error is Google::Cloud::AlreadyExistsError: alreadyExists: The resource 'entity.change.additions[0]' named 'instance-8.test.vmpooler.puppet.net. (A)' already exists
+          begin
+            change = zone.add name, 'A', 60, [created_instance['ip']]
+            debug_logger("#{change.id} - #{change.started_at} - #{change.status}") if change
+          rescue AlreadyExistsError => _e
+            # DNS setup is done only for new instances, so in the rare case where a DNS record already exists (it is stale) and we replace it.
+            # the error is Google::Cloud::AlreadyExistsError: alreadyExists: The resource 'entity.change.additions[0]' named 'instance-8.test.vmpooler.net. (A)' already exists
+            zone.replace(name, 'A', 60, [created_instance['ip']])
+          end
         end
 
         def dns_teardown(created_instance)
@@ -640,7 +640,7 @@ module Vmpooler
         end
 
         # Return a hash of VM data
-        # Provides vmname, hostname, template, poolname, boottime, status, zone, machine_type information
+        # Provides vmname, hostname, template, poolname, boottime, status, zone, machine_type, labels, label_fingerprint, ip information
         def generate_vm_hash(vm_object, pool_name)
           pool_configuration = pool_config(pool_name)
           return nil if pool_configuration.nil?
@@ -648,7 +648,7 @@ module Vmpooler
           {
             'name' => vm_object.name,
             'hostname' => vm_object.hostname,
-            'template' => pool_configuration&.key?('template') ? pool_configuration['template'] : nil, # TODO: get it from the API, not from config, but this is what vSphere does too!
+            'template' => pool_configuration&.key?('template') ? pool_configuration['template'] : nil, # was expecting to get it from API, not from config, but this is what vSphere does too!
             'poolname' => vm_object.labels&.key?('pool') ? vm_object.labels['pool'] : nil,
             'boottime' => vm_object.creation_timestamp,
             'status' => vm_object.status, # One of the following values: PROVISIONING, STAGING, RUNNING, STOPPING, SUSPENDING, SUSPENDED, REPAIRING, and TERMINATED
@@ -657,7 +657,6 @@ module Vmpooler
             'labels' => vm_object.labels,
             'label_fingerprint' => vm_object.label_fingerprint,
             'ip' => vm_object.network_interfaces ? vm_object.network_interfaces.first.network_ip : nil
-            # 'powerstate' => powerstate
           }
         end