Hi,
One of the most important things to keep in mind when using XML templates in NSO is the execution context.
Whenever you try to configure a list on the device data model (e.g. vrf, bgp-vfr, interface, etc.), the context is changing (and you should see it as well on the debug template output.
Whenever your template includes the root node (path that starts with '/...') you're effectively resetting the context, and that's what doesn't allow your template to "iterate" the different instances, and instead outputs the content from all instances on the path.
To avoid that, two things:
1. suppose that you have a service models such as:
list a {
leaf a-1;
leaf a-2;
}
and you want to use it to configure device model such as:
list x {
leaf x-1; //key
leaf x-2;
}
Your xml template should be something like this:
<x>
<x-1>{/a/a-1}</x-1>
<x-2>{a-2}</x-2>
...
In the debug template output, you will notice that the context is changing once you provided the key to the list on the target (device) model, and at this point you should provide a relative path, rather than an absolute one (not to reset the context).
2. While accessing entries on a list on the target model (as before), suppose that you want to use an element from outside of the current context, but without losing the context, you can make use of the xpath string() method, which will evaluate a given path without changing the context. For example:
<x>
<x-1>{/a/a-1}</x-1>
<x-2>{a-2}</x-2>
<x-3>{string(/some/far/away/path)}</x-3>
...
Notice on the debug output that the context will not change when using the string method.
Hope that helps!
Yftach
