libcni, skel: implement STATUS

libcni/api.go

@@ -114,6 +114,7 @@ type CNI interface {
 	ValidateNetwork(ctx context.Context, net *NetworkConfig) ([]string, error)
 
 	GCNetworkList(ctx context.Context, net *NetworkConfigList, args *GCArgs) error
+	GetStatusNetworkList(ctx context.Context, net *NetworkConfigList) error
 
 	GetCachedAttachments(containerID string) ([]*NetworkAttachment, error)
 }
@@ -829,6 +830,41 @@ func (c *CNIConfig) gcNetwork(ctx context.Context, net *NetworkConfig) error {
 	return invoke.ExecPluginWithoutResult(ctx, pluginPath, net.Bytes, args, c.exec)
 }
 
+func (c *CNIConfig) GetStatusNetworkList(ctx context.Context, list *NetworkConfigList) error {
+	// If the version doesn't support status, abort.
+	if gt, _ := version.GreaterThanOrEqualTo(list.CNIVersion, "1.1.0"); !gt {
+		return nil
+	}
+
+	inject := map[string]interface{}{
+		"name":       list.Name,
+		"cniVersion": list.CNIVersion,
+	}
+
+	for _, plugin := range list.Plugins {
+		// build config here
+		pluginConfig, err := InjectConf(plugin, inject)
+		if err != nil {
+			return fmt.Errorf("failed to generate configuration to get plugin STATUS %s: %w", plugin.Network.Type, err)
+		}
+		if err := c.getStatusNetwork(ctx, pluginConfig); err != nil {
+			return err // Don't collect errors here, so we return a clean error code.
+		}
+	}
+	return nil
+}
+
+func (c *CNIConfig) getStatusNetwork(ctx context.Context, net *NetworkConfig) error {
+	c.ensureExec()
+	pluginPath, err := c.exec.FindInPath(net.Network.Type, c.Path)
+	if err != nil {
+		return err
+	}
+	args := c.args("STATUS", &RuntimeConf{})
+
+	return invoke.ExecPluginWithoutResult(ctx, pluginPath, net.Bytes, args, c.exec)
+}
+
 // =====
 func (c *CNIConfig) args(action string, rt *RuntimeConf) *invoke.Args {
 	return &invoke.Args{

libcni/api_test.go

@@ -1580,6 +1580,44 @@ var _ = Describe("Invoking plugins", func() {
 				}
 			})
 		})
+		Describe("GetStatusNetworkList", func() {
+			It("issues a STATUS request", func() {
+				netConfigList, plugins = makePluginList("1.1.0", ipResult, rcMap)
+
+				err := cniConfig.GetStatusNetworkList(ctx, netConfigList)
+				Expect(err).NotTo(HaveOccurred())
+
+				debug, err := noop_debug.ReadDebug(plugins[0].debugFilePath)
+				Expect(err).NotTo(HaveOccurred())
+				Expect(debug.Command).To(Equal("STATUS"))
+			})
+
+			It("correctly reports an error", func() {
+				netConfigList, plugins = makePluginList("1.1.0", ipResult, rcMap)
+
+				plugins[1].debug.ReportError = "plugin error: banana"
+				plugins[1].debug.ReportErrorCode = 50
+				Expect(plugins[1].debug.WriteDebug(plugins[1].debugFilePath)).To(Succeed())
+
+				err := cniConfig.GetStatusNetworkList(ctx, netConfigList)
+				Expect(err).To(HaveOccurred())
+				var eerr *types.Error
+				Expect(errors.As(err, &eerr)).To(BeTrue())
+				Expect(eerr.Code).To(Equal(uint(50)))
+
+				debug, err := noop_debug.ReadDebug(plugins[0].debugFilePath)
+				Expect(err).NotTo(HaveOccurred())
+				Expect(debug.Command).To(Equal("STATUS"))
+
+				debug, err = noop_debug.ReadDebug(plugins[1].debugFilePath)
+				Expect(err).NotTo(HaveOccurred())
+				Expect(debug.Command).To(Equal("STATUS"))
+
+				debug, err = noop_debug.ReadDebug(plugins[2].debugFilePath)
+				Expect(err).NotTo(HaveOccurred())
+				Expect(debug.Command).To(Equal(""))
+			})
+		})
 	})
 
 	Describe("Invoking a sleep plugin", func() {

pkg/skel/skel.go

@@ -69,10 +69,11 @@ func (t *dispatcher) getCmdArgsFromEnv() (string, *CmdArgs, *types.Error) {
 			"CNI_COMMAND",
 			&cmd,
 			reqForCmdEntry{
-				"ADD":   true,
-				"CHECK": true,
-				"DEL":   true,
-				"GC":    true,
+				"ADD":    true,
+				"CHECK":  true,
+				"DEL":    true,
+				"GC":     true,
+				"STATUS": true,
 			},
 			nil,
 		},
@@ -120,10 +121,11 @@ func (t *dispatcher) getCmdArgsFromEnv() (string, *CmdArgs, *types.Error) {
 			"CNI_PATH",
 			&path,
 			reqForCmdEntry{
-				"ADD":   true,
-				"CHECK": true,
-				"DEL":   true,
-				"GC":    true,
+				"ADD":    true,
+				"CHECK":  true,
+				"DEL":    true,
+				"GC":     true,
+				"STATUS": true,
 			},
 			nil,
 		},
@@ -310,6 +312,28 @@ func (t *dispatcher) pluginMain(funcs CNIFuncs, versionInfo version.PluginInfo,
 			}
 		}
 		return types.NewError(types.ErrIncompatibleCNIVersion, "plugin version does not allow GC", "")
+	case "STATUS":
+		configVersion, err := t.ConfVersionDecoder.Decode(cmdArgs.StdinData)
+		if err != nil {
+			return types.NewError(types.ErrDecodingFailure, err.Error(), "")
+		}
+		if gtet, err := version.GreaterThanOrEqualTo(configVersion, "1.1.0"); err != nil {
+			return types.NewError(types.ErrDecodingFailure, err.Error(), "")
+		} else if !gtet {
+			return types.NewError(types.ErrIncompatibleCNIVersion, "config version does not allow STATUS", "")
+		}
+		for _, pluginVersion := range versionInfo.SupportedVersions() {
+			gtet, err := version.GreaterThanOrEqualTo(pluginVersion, configVersion)
+			if err != nil {
+				return types.NewError(types.ErrDecodingFailure, err.Error(), "")
+			} else if gtet {
+				if err := t.checkVersionAndCall(cmdArgs, versionInfo, funcs.Status); err != nil {
+					return err
+				}
+				return nil
+			}
+		}
+		return types.NewError(types.ErrIncompatibleCNIVersion, "plugin version does not allow STATUS", "")
 	case "VERSION":
 		if err := versionInfo.Encode(t.Stdout); err != nil {
 			return types.NewError(types.ErrIOFailure, err.Error(), "")
@@ -342,10 +366,11 @@ func PluginMainWithError(cmdAdd, cmdCheck, cmdDel func(_ *CmdArgs) error, versio
 // CNIFuncs contains a group of callback command funcs to be passed in as
 // parameters to the core "main" for a plugin.
 type CNIFuncs struct {
-	Add   func(_ *CmdArgs) error
-	Del   func(_ *CmdArgs) error
-	Check func(_ *CmdArgs) error
-	GC    func(_ *CmdArgs) error
+	Add    func(_ *CmdArgs) error
+	Del    func(_ *CmdArgs) error
+	Check  func(_ *CmdArgs) error
+	GC     func(_ *CmdArgs) error
+	Status func(_ *CmdArgs) error
 }
 
 // PluginMainFuncsWithError is the core "main" for a plugin. It accepts

plugins/test/noop/debug/debug.go

@@ -29,6 +29,7 @@ type Debug struct {
 	// Report* fields allow the test to control the behavior of the no-op plugin
 	ReportResult         string
 	ReportError          string
+	ReportErrorCode      uint
 	ReportStderr         string
 	ReportVersionSupport []string
 	ExitWithCode         int

plugins/test/noop/main.go

@@ -23,7 +23,6 @@ package main
 
 import (
 	"encoding/json"
-	"errors"
 	"fmt"
 	"io"
 	"os"
@@ -136,7 +135,14 @@ func debugBehavior(args *skel.CmdArgs, command string) error {
 	}
 	switch {
 	case debug.ReportError != "":
-		return errors.New(debug.ReportError)
+		ec := debug.ReportErrorCode
+		if ec == 0 {
+			ec = types.ErrInternal
+		}
+		return &types.Error{
+			Msg:  debug.ReportError,
+			Code: ec,
+		}
 	case debug.ReportResult == "PASSTHROUGH" || debug.ReportResult == "INJECT-DNS":
 		prevResult := netConf.PrevResult
 		if debug.ReportResult == "INJECT-DNS" {
@@ -212,6 +218,10 @@ func cmdGC(args *skel.CmdArgs) error {
 	return debugBehavior(args, "GC")
 }
 
+func cmdStatus(args *skel.CmdArgs) error {
+	return debugBehavior(args, "STATUS")
+}
+
 func saveStdin() ([]byte, error) {
 	// Read original stdin
 	stdinData, err := io.ReadAll(os.Stdin)
@@ -244,9 +254,10 @@ func main() {
 
 	supportedVersions := debugGetSupportedVersions(stdinData)
 	skel.PluginMainFuncs(skel.CNIFuncs{
-		Add:   cmdAdd,
-		Check: cmdCheck,
-		Del:   cmdDel,
-		GC:    cmdGC,
+		Add:    cmdAdd,
+		Check:  cmdCheck,
+		Del:    cmdDel,
+		GC:     cmdGC,
+		Status: cmdStatus,
 	}, version.PluginSupports(supportedVersions...), "CNI noop plugin v0.7.0")
 }