Problem supporting extra keys in pod network annotation

[SchSeba]

Problem supporting extra keys in pod network annotation

Acorrding to the de-facto standard documentation-
"All key names that do not include a period character are reserved to ensure this specification
may be extended in the future. Implementations that write keys other than those defined in this
specification must use reverse domain name notation (eg "​ org.foo.bar.key-name​ ") to
name the non-standard keys."

The problem is with the LoadArgs function

// LoadArgs parses args from a string in the form "K=V;K2=V2;..."
func LoadArgs(args string, container interface{}) error 

We find the keys by is name using this call keyField := GetKeyField(keyString, containerValue) but according to the de-facto standard documentation to define extra args with the name of "​ org.foo.bar.key-name​ " I need to have a variable called org.foo.bar.key-name and this is not possible.

I think we need to change the function of GetKeyField to read the json tag and not the variable name.

[dcbw]

@SchSeba how do those pod annotations actually get into CNI args? I'm not aware of pod annotations being passed to CNI plugins in either dockershim or CRIO...

That said, if for some reason LoadArgs doesn't allow key names with "." then that should be fixed...

[SchSeba]

@dcbw Using this PR k8snetworkplumbingwg/multus-cni#210 ( I change it for now because of this issue)

[dcbw]

@SchSeba Yeah, just found that PR independently. If you have a PR to fix the LoadArgs parsing, we'd entertain it :)