Remove Kubernetes PodInfoProvider and default to CNI initialization

cns/NetworkContainerContract.go

@@ -143,17 +143,6 @@ func (f PodInfoByIPProviderFunc) PodInfoByIP() (map[string]PodInfo, error) {
 	return f()
 }
 
-var GlobalPodInfoScheme podInfoScheme
-
-// podInfoScheme indicates which schema should be used when generating
-// the map key in the Key() function on a podInfo object.
-type podInfoScheme int
-
-const (
-	KubernetesPodInfoScheme podInfoScheme = iota
-	InterfaceIDPodInfoScheme
-)
-
 // PodInfo represents the object that we are providing network for.
 type PodInfo interface {
 	// InfraContainerID the CRI infra container for the pod namespace.
@@ -187,7 +176,6 @@ type podInfo struct {
 	KubernetesPodInfo
 	PodInfraContainerID string
 	PodInterfaceID      string
-	Version             podInfoScheme
 }
 
 func (p podInfo) String() string {
@@ -219,10 +207,7 @@ func (p *podInfo) InterfaceID() string {
 // composed of the CNI interfaceID, which is generated from the CRI infra
 // container ID and the pod net ns primary interface name.
 func (p *podInfo) Key() string {
-	if p.Version == InterfaceIDPodInfoScheme {
-		return p.PodInterfaceID
-	}
-	return p.PodName + ":" + p.PodNamespace
+	return p.PodInterfaceID
 }
 
 func (p *podInfo) Name() string {
@@ -251,7 +236,6 @@ func NewPodInfo(infraContainerID, interfaceID, name, namespace string) PodInfo {
 		},
 		PodInfraContainerID: infraContainerID,
 		PodInterfaceID:      interfaceID,
-		Version:             GlobalPodInfoScheme,
 	}
 }
 
@@ -262,7 +246,6 @@ func UnmarshalPodInfo(b []byte) (PodInfo, error) {
 	if err := json.Unmarshal(b, p); err != nil {
 		return nil, err
 	}
-	p.Version = GlobalPodInfoScheme
 	return p, nil
 }
 
@@ -273,7 +256,7 @@ func NewPodInfoFromIPConfigsRequest(req IPConfigsRequest) (PodInfo, error) {
 	if err != nil {
 		return nil, err
 	}
-	if GlobalPodInfoScheme == InterfaceIDPodInfoScheme && req.PodInterfaceID == "" {
+	if req.PodInterfaceID == "" {
 		return nil, fmt.Errorf("need interfaceID for pod info but request was empty")
 	}
 	p.(*podInfo).PodInfraContainerID = req.InfraContainerID

cns/NetworkContainerContract_test.go

@@ -57,8 +57,6 @@ func TestUnmarshalPodInfo(t *testing.T) {
 }
 
 func TestNewPodInfoFromIPConfigsRequest(t *testing.T) {
-	GlobalPodInfoScheme = InterfaceIDPodInfoScheme
-	defer func() { GlobalPodInfoScheme = KubernetesPodInfoScheme }()
 	tests := []struct {
 		name    string
 		req     IPConfigsRequest
@@ -79,7 +77,6 @@ func TestNewPodInfoFromIPConfigsRequest(t *testing.T) {
 				},
 				PodInterfaceID:      "abcdef-eth0",
 				PodInfraContainerID: "abcdef",
-				Version:             InterfaceIDPodInfoScheme,
 			},
 		},
 		{

cns/podprovider/cni/podinfoprovider.go

@@ -0,0 +1,49 @@
+package cni
+
+import (
+	"fmt"
+
+	"github.com/Azure/azure-container-networking/cni/api"
+	"github.com/Azure/azure-container-networking/cni/client"
+	"github.com/Azure/azure-container-networking/cns"
+	"github.com/pkg/errors"
+	kexec "k8s.io/utils/exec"
+)
+
+// NewCNIPodInfoProvider returns an implementation of cns.PodInfoByIPProvider
+// that execs out to the CNI and uses the response to build the PodInfo map.
+func NewCNIPodInfoProvider() (cns.PodInfoByIPProvider, error) {
+	return newCNIPodInfoProvider(kexec.New())
+}
+
+func newCNIPodInfoProvider(exec kexec.Interface) (cns.PodInfoByIPProvider, error) {
+	cli := client.New(exec)
+	state, err := cli.GetEndpointState()
+	if err != nil {
+		return nil, fmt.Errorf("failed to invoke CNI client.GetEndpointState(): %w", err)
+	}
+	return cns.PodInfoByIPProviderFunc(func() (map[string]cns.PodInfo, error) {
+		return cniStateToPodInfoByIP(state)
+	}), nil
+}
+
+// cniStateToPodInfoByIP converts an AzureCNIState dumped from a CNI exec
+// into a PodInfo map, using the endpoint IPs as keys in the map.
+// for pods with multiple IPs (such as in dualstack cases), this means multiple keys in the map
+// will point to the same pod information.
+func cniStateToPodInfoByIP(state *api.AzureCNIState) (map[string]cns.PodInfo, error) {
+	podInfoByIP := map[string]cns.PodInfo{}
+	for _, endpoint := range state.ContainerInterfaces {
+		for _, epIP := range endpoint.IPAddresses {
+			podInfo := cns.NewPodInfo(endpoint.ContainerID, endpoint.PodEndpointId, endpoint.PodName, endpoint.PodNamespace)
+
+			ipKey := epIP.IP.String()
+			if prevPodInfo, ok := podInfoByIP[ipKey]; ok {
+				return nil, errors.Wrapf(cns.ErrDuplicateIP, "duplicate ip %s found for different pods: pod: %+v, pod: %+v", ipKey, podInfo, prevPodInfo)
+			}
+
+			podInfoByIP[ipKey] = podInfo
+		}
+	}
+	return podInfoByIP, nil
+}