Merge pull request #142 from steveeJ/fix-loopback-result

Fix loopback result

plugins/main/loopback/loopback.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/appc/cni/pkg/ns"
 	"github.com/appc/cni/pkg/skel"
+	"github.com/appc/cni/pkg/types"
 	"github.com/vishvananda/netlink"
 )
 
@@ -27,11 +28,29 @@ func cmdAdd(args *skel.CmdArgs) error {
 		return err // not tested
 	}
 
-	return nil
+	result := types.Result{}
+	return result.Print()
 }
 
 func cmdDel(args *skel.CmdArgs) error {
-	// del does nothing, we're going to destroy the device anyway
+	args.IfName = "lo" // ignore config, this only works for loopback
+	err := ns.WithNetNSPath(args.Netns, false, func(hostNS *os.File) error {
+		link, err := netlink.LinkByName(args.IfName)
+		if err != nil {
+			return err // not tested
+		}
+
+		err = netlink.LinkSetDown(link)
+		if err != nil {
+			return err // not tested
+		}
+
+		return nil
+	})
+	if err != nil {
+		return err // not tested
+	}
+
 	return nil
 }
 

plugins/main/loopback/loopback_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/appc/cni/pkg/ns"
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+	"github.com/onsi/gomega/gbytes"
 	"github.com/onsi/gomega/gexec"
 )
 
@@ -18,30 +19,21 @@ var _ = Describe("Loopback", func() {
 		networkNS   string
 		containerID string
 		command     *exec.Cmd
+		environ     []string
 	)
 
 	BeforeEach(func() {
 		command = exec.Command(pathToLoPlugin)
-
-		environ := os.Environ()
-
 		containerID = "some-container-id"
 		networkNS = makeNetworkNS(containerID)
 
-		cniEnvVars := []string{
+		environ = []string{
-			fmt.Sprintf("CNI_COMMAND=%s", "ADD"),
 			fmt.Sprintf("CNI_CONTAINERID=%s", containerID),
 			fmt.Sprintf("CNI_NETNS=%s", networkNS),
 			fmt.Sprintf("CNI_IFNAME=%s", "this is ignored"),
 			fmt.Sprintf("CNI_ARGS=%s", "none"),
 			fmt.Sprintf("CNI_PATH=%s", "/some/test/path"),
 		}
-
-		for _, v := range cniEnvVars {
-			environ = append(environ, v)
-		}
-
-		command.Env = environ
 		command.Stdin = strings.NewReader("this doesn't matter")
 	})
 
@@ -51,9 +43,12 @@ var _ = Describe("Loopback", func() {
 
 	Context("when given a network namespace", func() {
 		It("sets the lo device to UP", func() {
+			command.Env = append(environ, fmt.Sprintf("CNI_COMMAND=%s", "ADD"))
+
 			session, err := gexec.Start(command, GinkgoWriter, GinkgoWriter)
 			Expect(err).NotTo(HaveOccurred())
 
+			Eventually(session).Should(gbytes.Say(`{.*}`))
 			Eventually(session).Should(gexec.Exit(0))
 
 			var lo *net.Interface
@@ -66,5 +61,25 @@ var _ = Describe("Loopback", func() {
 
 			Expect(lo.Flags & net.FlagUp).To(Equal(net.FlagUp))
 		})
+
+		It("sets the lo device to DOWN", func() {
+			command.Env = append(environ, fmt.Sprintf("CNI_COMMAND=%s", "DEL"))
+
+			session, err := gexec.Start(command, GinkgoWriter, GinkgoWriter)
+			Expect(err).NotTo(HaveOccurred())
+
+			Eventually(session).Should(gbytes.Say(``))
+			Eventually(session).Should(gexec.Exit(0))
+
+			var lo *net.Interface
+			err = ns.WithNetNSPath(networkNS, true, func(hostNS *os.File) error {
+				var err error
+				lo, err = net.InterfaceByName("lo")
+				return err
+			})
+			Expect(err).NotTo(HaveOccurred())
+
+			Expect(lo.Flags & net.FlagUp).NotTo(Equal(net.FlagUp))
+		})
 	})
 })