github.com/containerd/go-cni

A generic CNI library to provide APIs for CNI plugin interactions


License
Apache-2.0
Install
go get github.com/containerd/go-cni

Documentation

libcni

A generic CNI library to provide APIs for CNI plugin interactions. The library provides APIs to:

  • Setup networks for container namespace
  • Remove networks from container namespace
  • Query status of CNI network plugin initialization

libcni aims to support plugins that implement Container Network Interface

Usage

func main() {
	id := "123456"
	netns := "/proc/9999/ns/net"
	defaultIfName := "eth0"
	// Initialize library
	l = libcni.New(libcni.WithMinNetworkCount(2),
		libcni.WithLoNetwork(),
		libcni.WithPluginConfDir("/etc/mycni/net.d"),
		libcni.WithPluginDir([]string{"/opt/mycni/bin", "/opt/cni/bin"}),
		libcni.WithDefaultIfName(defaultIfName))

	// Setup network for namespace.
	labels := map[string]string{
		"K8S_POD_NAMESPACE":          "namespace1",
		"K8S_POD_NAME":               "pod1",
		"K8S_POD_INFRA_CONTAINER_ID": id,
	}
	result, err := l.Setup(id, netns, libcni.WithLabels(labels))
	if err != nil {
		return nil, fmt.Errorf("failed to setup network for namespace %q: %v", id, err)
	}
	defer func() {
		if retErr != nil {
			// Teardown network if an error is returned.
			if err := l.Remove(id, netns, libcni.WithLabels(labels)); err != nil {
				fmt.Errorf("Failed to destroy network for namespace %q", id)
			}
		}
	}()
	// Get IP of the default interface
	IP := result.Interfaces[defaultIfName].IPConfigs[0].IP.String()
	fmt.Printf("IP of the default interface %s:%s", defaultIfName, IP)
}