Very rough working example

lib/vmpooler/dns/gcp/clouddns.rb

@@ -7,8 +7,83 @@ module Vmpooler
   class PoolManager
     class Dns
       class Gcp
-        class Clouddns
-          # Your code goes here...
+        # This class represent a DNS plugin to CRUD resources in google clouddns.
+        class Clouddns < Vmpooler::PoolManager::Dns::Base
+          # The connection_pool method is normally used only for testing
+          attr_reader :connection_pool
+
+          def initialize(config, logger, metrics, redis_connection_pool, name, options)
+            super(config, logger, metrics, redis_connection_pool, name, options)
+
+            task_limit = global_config[:config].nil? || global_config[:config]['task_limit'].nil? ? 10 : global_config[:config]['task_limit'].to_i
+
+            default_connpool_size = [provided_pools.count, task_limit, 2].max
+            # connpool_size = provider_config['connection_pool_size'].nil? ? default_connpool_size : provider_config['connection_pool_size'].to_i
+            connpool_timeout = 60
+            # logger.log('d', "[#{name}] ConnPool - Creating a connection pool of size #{connpool_size} with timeout #{connpool_timeout}")
+            logger.log('d', "[#{name}] ConnPool - Creating a connection pool of size #{default_connpool_size} with timeout #{connpool_timeout}")
+            @connection_pool = Vmpooler::PoolManager::GenericConnectionPool.new(
+              metrics: metrics,
+              connpool_type: 'dns_connection_pool',
+              connpool_provider: name,
+              size: default_connpool_size,
+              # size: connpool_size,
+              timeout: connpool_timeout
+            ) do
+              logger.log('d', "[#{name}] Connection Pool - Creating a connection object")
+              # Need to wrap the vSphere connection object in another object. The generic connection pooler will preserve
+              # the object reference for the connection, which means it cannot "reconnect" by creating an entirely new connection
+              # object.  Instead by wrapping it in a Hash, the Hash object reference itself never changes but the content of the
+              # Hash can change, and is preserved across invocations.
+              new_conn = connect_to_gcp
+              { connection: new_conn }
+            end
+          end
+
+          def name
+            'gcp-clouddns'
+          end
+
+          def create_or_replace_record(hostname)
+            ip = get_ip(hostname)
+            connection.zone('vmpooler-example-com').add(hostname, 'A', 60, ip)
+          end
+
+          def connection
+            @connection_pool.with_metrics do |pool_object|
+              return ensured_gcp_connection(pool_object)
+            end
+          end
+
+          def ensured_gcp_connection(connection_pool_object)
+            connection_pool_object[:connection] = connect_to_gcp unless connection_pool_object[:connection]
+            connection_pool_object[:connection]
+          end
+
+          def connect_to_gcp
+            max_tries = global_config[:config]['max_tries'] || 3
+            retry_factor = global_config[:config]['retry_factor'] || 10
+            try = 1
+            begin
+              scopes = ['https://www.googleapis.com/auth/cloud-platform']
+  
+              Google::Auth.get_application_default(scopes)
+  
+              dns = Google::Cloud::Dns.new
+              # dns.authorization = authorization
+  
+              metrics.increment('connect.open')
+              dns
+            rescue StandardError => e
+              metrics.increment('connect.fail')
+              raise e if try >= max_tries
+  
+              sleep(try * retry_factor)
+              try += 1
+              retry
+            end
+          end
+
         end
       end
     end