Inheritance Issue

[no-such-anthony]

There appears to be an inheritance issue as found by Netigo @ https://nornir.discourse.group/t/inheritance-problem/645

If you recreate the inventory files at https://github.com/nornir-automation/nornir/blob/develop/docs/tutorial/inventory.ipynb

Then try

leaf01_bma = nr.inventory.hosts["leaf01.bma"]
print(leaf01_bma["domain"])  

The data is supposed to come from the group global, but instead comes from defaults.yaml, ie acme.local. It should be global.local as mentioned in the documentation.

I've attempted a possible patch but not sure how correct it is within the Nornir framework.

In nornir/core/inventory.py

Modify the group loop in _resolve_data

for g in self.groups:
    for k, v in g.data.items():
        if k not in processed:
            processed.append(k)
            result[k] = v

    for pg in g.groups:
        for k, v in pg.data.items():
            if k not in processed:
                processed.append(k)
                result[k] = v

Modify the group loop in __getitem__

    for g in self.groups:
        try:
            r = g.data[item]
            return r
        except KeyError:
            pass

        for pg in g.groups:
            try:
                r = pg.data[item]
                return r
            except KeyError:
                pass

[dbarrosop]

thanks for reporting, I opened #623 which should address this bug

[no-such-anthony]

Thanks! Re #623 - Looks great. I think it may still need a change of g.items() to g.data.items() in _resolve_data? And maybe a .values() test for this scenario?

[NetIgo]

Thank you.
Looks good.

[no-such-anthony]

Something that returns an ordered list of all the groups might help in _resolve_data and __getitem__? Example

    def __ordered_groups(self, groups):
        og = []
        for g in groups:
            og.append(g)
            if len(g.groups) > 0:
                og.extend(self.__ordered_groups(g.groups))
        return og

for g in self.__ordered_groups(self.groups):

[no-such-anthony]

Another function that needs checking on, __getattribute__ . If the username was in group global like the original example, it would be missed.

Possible fix for __getattribute__ , using something that returns a complete group list like above,

           for g in self.__ordered_groups(self.groups):
                r = object.__getattribute__(g, name)

[dbarrosop]

Thanks, I will try to find time to look into your comments. Just a tip, these comments would be easier to track on the PR alongside the code.