Receptive cluster agents

What does this MR do and why?

Draft: Receptive cluster agents

Changelog: added

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Related to #463427 (closed) #463426 (closed)

app/models/clusters/agents/url_configuration.rb

@@ -13,11 +13,12 @@ class UrlConfiguration < ApplicationRecord
 
       validates :url, url: { schemes: %w[grpc grpcs] }
 
+      validates :ca_cert, certificate: true, allow_blank: true
+      validates :tls_host, host: true, allow_blank: true
+
       with_options if: :certificate_auth? do
         validates :client_cert, certificate: true
         validates :client_key, certificate_key: true
-        validates :ca_cert, certificate: true, allow_blank: true
-        validates :tls_host, host: true, allow_blank: true
 
         validates :private_key, absence: true
       end
@@ -25,7 +26,7 @@ class UrlConfiguration < ApplicationRecord
       with_options if: :public_key_auth? do
         validates :private_key, presence: true
 
-        validates :client_cert, :client_key, :ca_cert, :tls_host, absence: true
+        validates :client_cert, :client_key, absence: true
       end
 
       nullify_if_blank :client_key, :client_cert, :ca_cert, :tls_host
@@ -42,6 +43,9 @@ class UrlConfiguration < ApplicationRecord
         revoked: 1
       }
 
+      after_create :set_agent_receptive!
+      after_destroy :unset_agent_receptive!
+
       private
 
       def public_key_auth?
@@ -51,6 +55,14 @@ def public_key_auth?
       def certificate_auth?
         !public_key_auth?
       end
+
+      def set_agent_receptive!
+        agent.update!(is_receptive: true)
+      end
+
+      def unset_agent_receptive!
+        agent.update!(is_receptive: false)
+      end
     end
   end
 end