UI allows deletion of an active trace file leading to an EACCES exception on Windows

[witling]

The management UI allows the deletion of a trace file that is actively worked on making any further actions regarding tracing impossible due to ubiquitous error message. The Delete event should at least assert that no tracing currently relies on that log.

Steps to reproduce

• Create a new trace inside Admin -> Tracing view
• Delete the newly created log file
  
• Window with erlang error will be prompted which does not disappear after reloading the page
  

Fixes

After restarting the RabbitMQ server, the UI is working again.

Environment

• RabbitMQ version: 3.7.18
• Erlang version: 21.3
• Browser: IE11
• Management UI: Admin -> Tracing
• Operating system: Windows Server 2016, v10.0.14393
• Errors reported in the js console: -
• RabbitMQ plugin information via rabbitmq-plugins list
  [ * ] rabbitmq_event_exchange 3.7.18
  [e * ] rabbitmq_management 3.7.18
  [e * ] rabbitmq_management_agent 3.7.18
  [E * ] rabbitmq_tracing 3.7.18
  [e * ] rabbitmq_web_dispatch 3.7.18

Logs

2019-10-09 13:39:27.418 [info] <0.676.0> Enabling tracing for vhost '/'
2019-10-09 13:39:27.433 [info] <0.726.0> Tracer opened log file "/var/tmp/rabbitmq-tracing/all.log" with format json
2019-10-09 13:59:15.059 [warning] <0.2825.0> Node rabbit@---------- could not be contacted: {badrpc,
                                                {'EXIT',
                                                 {{badmatch,{error,eacces}},
                                                  [{rabbit_tracing_files,
                                                    file_info,1,
                                                    [{file,
                                                      "src/rabbit_tracing_files.erl"},
                                                     {line,49}]},
                                                   {rabbit_tracing_files,
                                                    '-list/0-lc$^0/1-0-',1,
                                                    [{file,
                                                      "src/rabbit_tracing_files.erl"},
                                                     {line,29}]},
                                                   {rpc,local_call,3,
                                                    [{file,"rpc.erl"},
                                                     {line,321}]},
                                                   {rabbit_tracing_util,
                                                    apply_on_node,5,
                                                    [{file,
                                                      "src/rabbit_tracing_util.erl"},
                                                     {line,16}]},
                                                   {rabbit_tracing_wm_files,
                                                    to_json,2,
                                                    [{file,
                                                      "src/rabbit_tracing_wm_files.erl"},
                                                     {line,32}]},
                                                   {cowboy_rest,call,3,
                                                    [{file,
                                                      "src/cowboy_rest.erl"},
                                                     {line,1576}]},
                                                   {cowboy_rest,
                                                    set_resp_body,2,
                                                    [{file,
                                                      "src/cowboy_rest.erl"},
                                                     {line,1466}]},
                                                   {cowboy_rest,upgrade,4,
                                                    [{file,
                                                      "src/cowboy_rest.erl"},
                                                     {line,288}]}]}}}

[witling]

move issue to rabbitmq-tracing?

[lukebakken]

Can't reproduce on Linux. Guaranteed this is a win32-only problem (eacces).