Handle pod delete with non-existent IPs

cmd/whereabouts.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-
 	"github.com/containernetworking/cni/pkg/skel"
 	cnitypes "github.com/containernetworking/cni/pkg/types"
 	"github.com/containernetworking/cni/pkg/types/current"
@@ -78,11 +77,18 @@ func cmdDel(args *skel.CmdArgs) error {
 	logging.Debugf("ContainerID: %v", args.ContainerID)
 
 	_, err = storage.IPManagement(types.Deallocate, *ipamConf, args.ContainerID)
-	if err != nil {
-		logging.Verbosef("WARNING: Problem deallocating IP: %s", err)
-		// return fmt.Errorf("Error deallocating IP: %s", err)
-	}
 
+  if err != nil {
+		re, ok := err.(*types.IPNotFoundError)
+
+    if ok {
+			logging.Debugf("Cannot deallocate IP, it might not have been assigned by us, so ignoring. %s", re)
+		} else {
+			logging.Errorf("Error deallocating IP: %s", err)
+			return fmt.Errorf("Error deallocating IP: %s", err)
+		}
+
+  }
 	return nil
 }
 

pkg/allocate/allocate.go

@@ -1,6 +1,7 @@
 package allocate
 
 import (
+	//"errors"
 	"fmt"
 	"math/big"
 	"net"
@@ -59,7 +60,9 @@ func IterateForDeallocation(reservelist []types.IPReservation, containerID strin
 
 	// Check if it's a valid index
 	if foundidx < 0 {
-		return reservelist, fmt.Errorf("Did not find reserved IP for container %v", containerID)
+		return reservelist, &types.IPNotFoundError {
+			ContainerID: containerID,
+		}
 	}
 
 	updatedreservelist := removeIdxFromSlice(reservelist, foundidx)

pkg/types/types.go

@@ -2,7 +2,7 @@ package types
 
 import (
 	"net"
-
+    "fmt"
 	cnitypes "github.com/containernetworking/cni/pkg/types"
 )
 
@@ -79,3 +79,13 @@ const (
 	// Deallocate operation identifier
 	Deallocate = 1
 )
+
+
+// IPNotFoundError represents an error finding a specific IP during the deallocation process for a container.
+type IPNotFoundError struct {
+	ContainerID string
+}
+
+func (e *IPNotFoundError) Error() string {
+	return fmt.Sprintf("Did not find reserved IP for container %v", e.ContainerID)
+}