Merge ~guoqiao/charm-nrpe:LP1915106-skip-unfound-ifaces into charm-nrpe:master

[Joe Guo]

add --skip-unfound-ifaces to check_netlinks.py

Add an new boolean option `netlinks_skip_unfound_ifaces` in config.yaml.
When True, add --skip-unfound-ifaces to check_netlinks.py.

LP: #1915106

[Joe Guo (guoqiao)]

tested locally, when netlink_skip_unfound_ifaces = True, the render result will be:

ubuntu@juju-5e35e2-0:/etc/nagios/nrpe.d$ cat check_netlinks_eth0.cfg
# Netlinks status (eth0) (sub)
command[check_netlinks_eth0]=/usr/local/lib/nagios/plugins/check_netlinks.py --skip-unfound-ifaces -i eth0 -m 9000 -s 25000

which is as expected.

[Xav Paice (xavpaice)]

lgtm

review: Approve

[Linda Guo (lihuiguo)]

looks good, +1

review: Approve

[Joe Guo (guoqiao)]

Merged into master as 9010e2f4ad33a3e54c8fd57d02b37e28c18ef191.

diff --git a/config.yaml b/config.yaml
index 2c9eefd..80cf9cf 100644
--- a/config.yaml
+++ b/config.yaml
@@ -146,6 +146,11 @@ options:
         - bond0.25 mtu:1500 speed:50000
         - ens3 mtu:1500 speed:-1 desc:openstack_iface
         - ...
+  netlinks_skip_unfound_ifaces:
+    default: False
+    type: boolean
+    description: |
+        add --skip-unfound-ifaces to check_netlinks.py.
   monitors:
     default: ''
     type: string
diff --git a/hooks/nrpe_helpers.py b/hooks/nrpe_helpers.py
index cc63386..a8c4fde 100644
--- a/hooks/nrpe_helpers.py
+++ b/hooks/nrpe_helpers.py
@@ -521,11 +521,13 @@ class SubordinateCheckDefinitions(dict):
 
         if hookenv.config("netlinks"):
             ifaces = yaml.safe_load(hookenv.config("netlinks"))
+            cmd_exec = local_plugin_dir + "check_netlinks.py"
+            if hookenv.config("netlinks_skip_unfound_ifaces"):
+                cmd_exec += " --skip-unfound-ifaces"
             d_ifaces = self.parse_netlinks(ifaces)
             for iface in d_ifaces:
                 description = "Netlinks status ({})".format(iface)
                 cmd_name = "check_netlinks_{}".format(iface)
-                cmd_exec = local_plugin_dir + "check_netlinks.py"
                 cmd_params = d_ifaces[iface]
                 netlink_check = {
                     "description": description,