Telgraf Helm Chart does create Service config for snmp_trap plugin

[mwmahlberg]

When the input plugin snmp_trap is used the helm chart does not render a service.

This is due to the fact that there is no special treatment defined for itin the service template, beginning from l22:

helm-charts/charts/telegraf/templates/service.yaml

Lines 22 to 93 in fe0d58b

	{{- range $key, $value := . -}}
	{{- $tp := typeOf $value -}}
	{{- if eq $key "http_listener" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "http-listener"
	{{- end }}
	{{- if eq $key "influxdb_listener" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "influxdb-listener"
	{{- end }}
	{{- if eq $key "http_listener_v2" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "http-listener-v2"
	{{- end }}
	{{- if eq $key "influxdb_v2_listener" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "influxdb-v2-listener"
	{{- end }}
	{{- if eq $key "opentelemetry" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "opentelemetry"
	{{- end }}
	{{- if eq $key "statsd" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	protocol: "UDP"
	name: "statsd"
	{{- end }}
	{{- if eq $key "tcp_listener" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "tcp-listener"
	{{- end }}
	{{- if eq $key "udp_listener" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	protocol: "UDP"
	name: "udp-listener"
	{{- end }}
	{{- if eq $key "webhooks" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	name: "webhooks"
	{{- end }}
	{{- if eq $key "syslog" }}
	{{- if regexMatch "^(tcp|udp).*" $value.server }}
	- port: {{ regexFind "[0-9]+$" $value.server | int64 }}
	targetPort: {{ regexFind "[0-9]+$" $value.server | int64 }}
	protocol: {{ upper (substr 0 3 $value.server) }}
	name: "syslog"
	{{- end }}
	{{- end }}
	{{- if eq $key "socket_listener" }}
	{{- if or (hasPrefix "udp" $value.service_address) (hasPrefix "tcp" $value.service_address) }}
	- port: {{ regexFind "[0-9]+$" $value.service_address | int64 }}
	targetPort: {{ regexFind "[0-9]+$" $value.service_address | int64 }}
	protocol: {{ upper (substr 0 3 $value.service_address) }}
	name: {{ printf "%s-%s" "socket-listener" (regexFind "[0-9]+$" $value.service_address) }}
	{{- end }}
	{{- end }}
	{{- if eq $key "cisco_telemetry_mdt" }}
	- port: {{ trimPrefix ":" $value.service_address | int64 }}
	targetPort: {{ trimPrefix ":" $value.service_address | int64 }}
	protocol: "TCP"
	name: "cisco-telemetry-mdt"
	{{- end }}
	{{- end -}}

The result is that while telegraf listens on the SNMP traps within the pod, the listener is not accessible from the outside.