[API] Fix config file race condition and improve test cases for DNS update hooks
(Total: 0.00 h)
Node.dns_server_update() in source:services/api/app/models/node.rb is currently vulnerable to the following race (fixable by using a tempfile library):
- Request handler A writes hostname.conf.tmp.
- Request handler B opens hostname.conf.tmp for writing.
- Request handler A issues the move command.
Catch only the expected exceptions on the various write and update operations (IOError and SystemCallError?), not unexpected ones.