The opennebula-libvirt-exporter produces incomplete data during concurrent requests.

[Paucpauc]

Description
The opennebula-libvirt-exporter produces incomplete data during concurrent requests.

To Reproduce

$ curl 127.0.0.1:9926/metrics -i -s > m1 & curl 127.0.0.1:9926/metrics -i -s > m2
$ ls -l m1 m2
-rw-r--r-- 1 user user 49009 Jan 18 19:45 m1
-rw-r--r-- 1 user user  6776 Jan 18 19:45 m2

Expected behavior
Both m1 and m2 should have complete data and similar file sizes.

Details

• Affected Component: opennebula-libvirt-exporter
• Hypervisor: KVM
• Version: 6.10.0

Additional context
A naive solution to this issue might involve setting a lock to ensure data consistency:

--- /usr/lib/one/libvirt_exporter/libvirt_exporter.rb    2025-01-18 19:55:42.492027428 +0000
+++ /tmp/libvirt_exporter.rb    2025-01-18 19:55:34.824001932 +0000
@@ -73,6 +73,7 @@
 # Default Options
 set :bind, '0.0.0.0'
 set :port, 9926
+set :lock, true

 # Run the Sinatra application
 set :run, false