Hardcoding the list separator character as ":" causes CNI to fail when parsing
CNI_PATH on other operating systems. For example, Windows uses ";" as list
separator because ":" can legally appear in paths such as "C:\path\to\file".
This change replaces use of ":" with OS-agnostic APIs or os.PathListSeparator.
Fixes #358
Updates the spec and plugins to return an array of interfaces and IP details
to the runtime including:
- interface names and MAC addresses configured by the plugin
- whether the interfaces are sandboxed (container/VM) or host (bridge, veth, etc)
- multiple IP addresses configured by IPAM and which interface they
have been assigned to
Returning interface details is useful for runtimes, as well as allowing
more flexible chaining of CNI plugins themselves. For example, some
meta plugins may need to know the host-side interface to be able to
apply firewall or traffic shaping rules to the container.
Based on previous discussions on the CNI maintainers calls, the spec is
unclear on 1) when CNI_ARGS should be used and 2) the fact the dynamic
config can be passed in through the network JSON.
This PR makes it clear that per-container config can be passed in
through the network JSON, adding a top level `args` field into
which orchestrators can add additional metadata without worrying that
plugins might reject the additional data. It also allows for plugins to
reject unknown fields passed in at the top level.
Using JSON is preferable to CNI_ARGS since it allows namespaced and
structured data. CNI_ARGS is a flat list of KV pairs which has reserved
characters with no escaping rules defined.
CNI_ARGS may still be used by orchestrators that want the simplicity of
passing the network config JSON as specified by the user, unchanged
through to the CNI plugin. But for any kind of structured data, it's
recommended that the `args` field in the JSON is used instead.
Version all artifacts using semantic versioning
so that plugins and container runtimes coded against
different versions of the spec can interoperate.
Fixes #44
