Add "embedded_tags" in GNMI Plugin

[purifp]

Feature Request

Add "embedded_tags" in GNMI Plugin

Proposal:

We need add for GNMI the feature "embedded_tags" like the plugin "cisco_telemetry_mdt" has:

https://github.com/influxdata/telegraf/tree/master/plugins/inputs/cisco_telemetry_mdt

Define (for certain nested telemetry measurements with embedded tags) which fields are tags
embedded_tags = ["Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/input/service-policy-names/service-policy-instance/statistics/class-stats/class-name"]

Current behavior:

In some yang models (iosxr telemetry) there are certain fields that are defined like a fields but really they are tags, for example this measure
"Cisco-IOS-XR-qos-ma-oper:qos/interface-table/interface/input/service-policy-names/service-policy-instance/statistics/class-stats/class-name"

IOSXR Routers send "source","interface-name","service-policy-name" like tags but can be more than one "class-name" in one "service-policy-name". In our case, we have 7 different "class-name" with statistics of each class-name in a service-policy and telegraf only sent to the output the last one because we can not change this field to tag in the input plugin

Desired behavior:

To define some fields like tags in input.

Use case:

IOSXR Telemetry

[kb70]

Hi,
isn't that very similar to issue #7462 ?

[patrikh-dev]

this was fixed in cisco_telemetry_mdt plugin by @sbyx #6322 but unfortunately still missing in gnmi

[bofh16]

Hello, have you already undestanding of the eventual deployment path for this feature, please?

[sjwang90]

This should be addressed by #7484 which has been merged into main. Please test the nightlies and feel free to re-open if it doesn't cover your use case.

[bofh16]

Hello,
It doesn't seem to work.

$ telegraf --config telegraf_1.conf
2022-03-08T11:48:05Z E! [telegraf] Error running agent: Error loading config file telegraf_1.conf: plugin inputs.gnmi: line 57: configuration specified the fields ["embedded_tags"], but they weren't used
$ telegraf --version
Telegraf 1.22.0-2c2fcc46 (git: master 2c2fcc4)