[IOS XR] openconfig-telemetry persistent-subscriptions implementation is inconsistent with model

[nleiva]

Just sharing this as FYI as it's not a model issue. I've been hit by this now twice, so I'm sharing it to hopefully save someone time in the future.

This is what the model has:

{
    "openconfig-telemetry:telemetry-system": {
      "subscriptions": {
        "persistent-subscriptions": {
          "persistent-subscription": [
            {
              "name": "BGP",              
              "config": {
                "name": "BGP"
              }
            }
          ]
        }
      }
    }
  }

Versus what Cisco IOS XR implements (changes in key names):

{
    "openconfig-telemetry:telemetry-system": {
      "subscriptions": {
        "persistent": {
          "subscription": [
            {
              "subscription-id": "BGP",
              "config": {
                "subscription-id": "BGP"
              }
            }
          ]
        }
      }
    }
  }

If you want to use ygot for example to configure a Telemetry subscription on an IOS XR device, you'd need to slightly hack the model to account for this difference. Here are the changes requiered to have the keys match: https://github.com/PacktPublishing/Network-Automation-with-Go/commit/98ac674d518f3ea066749d606b71c6f3e929499d.