Bug #6819
closedproxy should raise an exception when it can't acquire a lock on a temp file
Description
Ran into this issue after a disk filled up on a DHCP proxy and had been cleaned up.
To reproduce, touch /tmp/foreman-proxy_10.10.10.0_24.tmp.lock. Then in the UI, when creating a new host, click "Suggest new" on the network tab for 10.10.10.0/24. Watch the foreman-proxy log and you will see this stacktrace:
E, [2014-07-29T15:16:10.925300 #6893] ERROR -- : undefined method `reopen' for nil:NilClass
D, [2014-07-29T15:16:10.925398 #6893] DEBUG -- : /usr/share/foreman-proxy/bin/../lib/proxy/dhcp/subnet.rb:135:in `set_index_and_unlock'
/usr/share/foreman-proxy/bin/../lib/proxy/dhcp/subnet.rb:177:in `unused_ip'
/usr/share/foreman-proxy/bin/../lib/dhcp_api.rb:73:in `GET /dhcp/:network/unused_ip'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:863:in `call'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:863:in `route'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:521:in `instance_eval'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:521:in `route_eval'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:500:in `route!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:497:in `catch'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:497:in `route!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:476:in `each'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:476:in `route!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:601:in `dispatch!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:411:in `call!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `instance_eval'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `invoke'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `catch'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `invoke'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:411:in `call!'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:399:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/methodoverride.rb:24:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/showexceptions.rb:24:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/commonlogger.rb:18:in `call'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:979:in `call'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:1005:in `synchronize'
/usr/lib/ruby/gems/1.8/gems/sinatra-1.0/lib/sinatra/base.rb:979:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/content_length.rb:13:in `call'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/handler/webrick.rb:48:in `service'
/usr/lib/ruby/1.8/webrick/httpserver.rb:104:in `service'
/usr/lib/ruby/1.8/webrick/httpserver.rb:65:in `run'
/usr/lib/ruby/1.8/webrick/server.rb:173:in `start_thread'
/usr/lib/ruby/1.8/webrick/server.rb:162:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:162:in `start_thread'
/usr/lib/ruby/1.8/webrick/server.rb:95:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:92:in `each'
/usr/lib/ruby/1.8/webrick/server.rb:92:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:23:in `start'
/usr/lib/ruby/1.8/webrick/server.rb:82:in `start'
/usr/lib/ruby/gems/1.8/gems/rack-1.1.0/lib/rack/handler/webrick.rb:14:in `run'
/usr/share/foreman-proxy/bin/../lib/sinatra-patch.rb:42:in `run!'
/usr/share/foreman-proxy/bin/smart-proxy:44
I traced this back to a lock file being left on the filesystem (ie /tmp/foreman-proxy_10.10.10.0_24.tmp.lock). I think the proxy should log that the lock could not be acquired, and perhaps raise an exception and warn the user in the UI.