T973: add basic node_exporter implementation

[rebortg]

Change Summary

Implement basic node_exporter function

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

https://vyos.dev/T973

Related PR(s)

vyos/vyos-build#757

Component(s) name

node_exporter

Proposed changes

add new feature node_exporter with vrf support.

How to test

# use defaults:
set service monitoring node-exporter

# all config
set service monitoring node-exporter listen-address 10.10.10.1
set service monitoring node-exporter port 9999
set service monitoring node-exporter vrf mgmt

Smoketest result

vyos@vyos:~$ /usr/libexec/vyos/tests/smoke/cli/test_service_monitoring_node-exporter.py
test_01_basic_config (__main__.TestMonitoringNodeExporter.test_01_basic_config) ... ok

----------------------------------------------------------------------
Ran 1 test in 4.832s

OK

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly

[github-actions]

👍
No issues in PR Title / Commit Title

[github-actions]

✅ No issues found in unused-imports check.. Please refer the workflow run

[sever-sever]

Probably requires to disable by default the service here https://github.com/vyos/vyos-build/blob/2b9303d0bd6b43bd92e2b2e9835a048877a63e11/data/live-build-config/hooks/live/18-enable-disable_services.chroot#L52

[rebortg]

Probably requires to disable by default the service here https://github.com/vyos/vyos-build/blob/2b9303d0bd6b43bd92e2b2e9835a048877a63e11/data/live-build-config/hooks/live/18-enable-disable_services.chroot#L52

there is no service file in the node-exporter deb. The service file is create and delete by configure the feature

[sever-sever]

there is no service file in the node-exporter deb. The service file is create and delete by configure the feature

For example, what will happen if I configure the service node exporter via VyOS CLI and reboot the router without saving?

[rebortg]

there is no service file in the node-exporter deb. The service file is create and delete by configure the feature

For example, what will happen if I configure the service node exporter via VyOS CLI and reboot the router without saving?

good point. i tryed it.

the service file is present in /etc/systemd/system/ but it is not enabled for autostart and so the service is not started

[github-actions]

CI integration ❌ failed!

Details

CI logs

• CLI Smoketests ❌ failed
• Config tests 👍 passed
• RAID1 tests 👍 passed
• TPM tests 👍 passed