Re: [PATCH net-next 3/3] tools: ynl: add more info to KeyErrors on missing attrs

[Donald Hunter <donald.hunter@gmail.com>]

Jakub Kicinski <kuba@kernel.org> writes:

> When developing specs its useful to know which attr space
> YNL was trying to find an attribute in on key error.
>
> Instead of printing:
>  KeyError: 0
> add info about the space:
>  Exception: Space 'vport' has no attribute with value '0'
>
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
> CC: donald.hunter@gmail.com
> ---
>  tools/net/ynl/lib/ynl.py | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/tools/net/ynl/lib/ynl.py b/tools/net/ynl/lib/ynl.py
> index 3ca28d4bcb18..6951bcc7efdc 100644
> --- a/tools/net/ynl/lib/ynl.py
> +++ b/tools/net/ynl/lib/ynl.py
> @@ -395,7 +395,10 @@ genl_family_name_to_id = None
>                               self.family.genl_family['mcast'][mcast_name])
>  
>      def _add_attr(self, space, name, value):
> -        attr = self.attr_sets[space][name]
> +        try:
> +            attr = self.attr_sets[space][name]
> +        except KeyError:
> +            raise Exception(f"Space '{space}' has no attribute '{name}'")
>          nl_type = attr.value
>          if attr["type"] == 'nest':
>              nl_type |= Netlink.NLA_F_NESTED
> @@ -450,7 +453,10 @@ genl_family_name_to_id = None
>          attr_space = self.attr_sets[space]
>          rsp = dict()
>          for attr in attrs:
> -            attr_spec = attr_space.attrs_by_val[attr.type]
> +            try:
> +                attr_spec = attr_space.attrs_by_val[attr.type]
> +            except KeyError:
> +                raise Exception(f"Space '{space}' has no attribute with value '{attr.type}'")
>              if attr_spec["type"] == 'nest':
>                  subdict = self._decode(NlAttrs(attr.raw), attr_spec['nested-attributes'])
>                  decoded = subdict
> @@ -479,7 +485,10 @@ genl_family_name_to_id = None
>  
>      def _decode_extack_path(self, attrs, attr_set, offset, target):
>          for attr in attrs:
> -            attr_spec = attr_set.attrs_by_val[attr.type]
> +            try:
> +                attr_spec = attr_set.attrs_by_val[attr.type]
> +            except KeyError:
> +                raise Exception(f"Space '{attr_set.name}' has no attribute with value '{attr.type}'")
>              if offset > target:
>                  break
>              if offset == target:

Reviewed-by: Donald Hunter <donald.hunter@gmail.com>