Fix backend_apis associations

Author: mayorova

app/lib/backend_api_logic/service_extension.rb

@@ -33,7 +33,11 @@ def backend_api_config
       end
 
       def backend_api
-        @backend_api ||= backend_api_configs.first&.backend_api || account.backend_apis.build(system_name: service_system_name, name: "#{service_name} Backend", description: "Backend of #{service_name}")
+        return @backend_api if @backend_api&.persisted?
+
+        @backend_api = backend_api_configs.first&.backend_api ||
+                       @backend_api
+        @backend_api ||= account.backend_apis.build(system_name: service_system_name, name: "#{service_name} Backend", description: "Backend of #{service_name}")
       end
 
       def update!(attrs = {})

test/factories/other.rb

@@ -46,6 +46,10 @@
     association(:account, :factory => :provider_account)
     after(:create) do |record|
       record.service_tokens.first_or_create!(value: 'token')
+      # Proxy validation during service creation calls account.backend_apis.build(...),
+      # which adds an unpersisted BackendApi to the association. Remove it to prevent
+      # validation failures in later operations on the account.
+      record.account.backend_apis.target.delete_if { |ba| !ba.persisted? }
     end
   end
 

test/factories/simple.rb

@@ -79,6 +79,10 @@
     association(:account, :factory => :simple_provider)
     after(:create) do |record|
       record.service_tokens.first_or_create!(value: 'token')
+      # Proxy validation during service creation calls account.backend_apis.build(...),
+      # which adds an unpersisted BackendApi to the association. Remove it to prevent
+      # validation failures in later operations on the account.
+      record.account.backend_apis.target.delete_if { |ba| !ba.persisted? }
     end
 
     trait :with_default_backend_api do