resume and complete gc impl

Signed-off-by: Henry Wang <henwang@amazon.com>

libcni/api.go

@@ -23,7 +23,6 @@ package libcni
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -114,7 +113,7 @@ type CNI interface {
 	ValidateNetworkList(ctx context.Context, net *NetworkConfigList) ([]string, error)
 	ValidateNetwork(ctx context.Context, net *NetworkConfig) ([]string, error)
 
-	GCNetworkList(ctx context.Context, net *NetworkConfigList, args GCArgs) error
+	GCNetworkList(ctx context.Context, net *NetworkConfigList, args *GCArgs) error
 
 	GetCachedAttachments(containerID string) ([]*NetworkAttachment, error)
 }
@@ -758,7 +757,7 @@ func (c *CNIConfig) GetVersionInfo(ctx context.Context, pluginType string) (vers
 // GCNetworkList will do two things
 // - dump the list of cached attachments, and issue deletes as necessary
 // - issue a GC to the underlying plugins (if the version is high enough)
-func (c *CNIConfig) GCNetworkList(ctx context.Context, list *NetworkConfigList, args GCArgs) error {
+func (c *CNIConfig) GCNetworkList(ctx context.Context, list *NetworkConfigList, args *GCArgs) error {
 	// First, get the list of cached attachments
 	cachedAttachments, err := c.GetCachedAttachments("")
 	if err != nil {
@@ -770,28 +769,29 @@ func (c *CNIConfig) GCNetworkList(ctx context.Context, list *NetworkConfigList,
 		validAttachments[a] = nil
 	}
 
-	errs := []error{}
+	var errs []error
 
 	for _, cachedAttachment := range cachedAttachments {
 		if cachedAttachment.Network != list.Name {
 			continue
 		}
 		// we found this attachment
-		if _, ok := validAttachments[GCAttachment{ContainerID: cachedAttachment.ContainerID, IfName: cachedAttachment.IfName}]; ok {
+		gca := GCAttachment{
+			ContainerID: cachedAttachment.ContainerID,
+			IfName:      cachedAttachment.IfName,
+		}
+		if _, ok := validAttachments[gca]; ok {
 			continue
 		}
-
-		// otherwise, this attachment wasn't valid
-		// and we should issue a CNI DEL
+		// otherwise, this attachment wasn't valid and we should issue a CNI DEL
 		rt := RuntimeConf{
 			ContainerID:    cachedAttachment.ContainerID,
 			NetNS:          cachedAttachment.NetNS,
 			IfName:         cachedAttachment.IfName,
 			Args:           cachedAttachment.CniArgs,
 			CapabilityArgs: cachedAttachment.CapabilityArgs,
 		}
-		err := c.DelNetworkList(ctx, list, &rt)
-		if err != nil {
+		if err := c.DelNetworkList(ctx, list, &rt); err != nil {
 			errs = append(errs, fmt.Errorf("failed to delete stale attachment %s %s: %w", rt.ContainerID, rt.IfName, err))
 		}
 	}
@@ -807,20 +807,15 @@ func (c *CNIConfig) GCNetworkList(ctx context.Context, list *NetworkConfigList,
 			// build config here
 			pluginConfig, err := InjectConf(plugin, inject)
 			if err != nil {
-				errs = append(errs, fmt.Errorf(
-					"failed to generate configuration to GC plugin %s: %w",
-					plugin.Network.Type, err))
+				errs = append(errs, fmt.Errorf("failed to generate configuration to GC plugin %s: %w", plugin.Network.Type, err))
 			}
 			if err := c.gcNetwork(ctx, pluginConfig); err != nil {
-				errs = append(errs, fmt.Errorf(
-					"failed to GC plugin %s: %w",
-					plugin.Network.Type, err))
+				errs = append(errs, fmt.Errorf("failed to GC plugin %s: %w", plugin.Network.Type, err))
 			}
 		}
-
 	}
 
-	return errors.Join(errs...)
+	return joinErrors(errs...)
 }
 
 func (c *CNIConfig) gcNetwork(ctx context.Context, net *NetworkConfig) error {

libcni/api_test.go

@@ -1513,16 +1513,71 @@ var _ = Describe("Invoking plugins", func() {
 				_, err := cniConfig.AddNetworkList(ctx, netConfigList, runtimeConfig)
 				Expect(err).NotTo(HaveOccurred())
 
+				By("Issuing a GC with valid networks")
+				gcargs := &libcni.GCArgs{
+					ValidAttachments: []libcni.GCAttachment{{
+						ContainerID: runtimeConfig.ContainerID,
+						IfName:      runtimeConfig.IfName,
+					}},
+				}
+				err = cniConfig.GCNetworkList(ctx, netConfigList, gcargs)
+				Expect(err).NotTo(HaveOccurred())
+
 				By("Issuing a GC with no valid networks")
-				err = cniConfig.GCNetworkList(ctx, netConfigList, libcni.GCArgs{
-					ValidAttachments: []libcni.GCAttachment{},
-				})
+				gcargs.ValidAttachments = nil
+				err = cniConfig.GCNetworkList(ctx, netConfigList, gcargs)
 				Expect(err).NotTo(HaveOccurred())
 
 				commands, err := noop_debug.ReadCommandLog(plugins[0].commandFilePath)
 				Expect(err).NotTo(HaveOccurred())
-				Expect(commands).To(Equal([]string{"ADD", "DEL", "GC"}))
-
+				Expect(commands).To(HaveLen(4))
+
+				validations := []struct {
+					name string
+					fn   func(entry noop_debug.CmdLogEntry)
+				}{
+					{
+						name: "ADD",
+						fn: func(entry noop_debug.CmdLogEntry) {
+							Expect(entry.CmdArgs.ContainerID).To(Equal(runtimeConfig.ContainerID))
+							Expect(entry.CmdArgs.IfName).To(Equal(runtimeConfig.IfName))
+						},
+					},
+					{
+						name: "GC",
+						fn: func(entry noop_debug.CmdLogEntry) {
+							var conf struct {
+								Attachments []map[string]string `json:"cni.dev/valid-attachments"`
+							}
+							err = json.Unmarshal(entry.CmdArgs.StdinData, &conf)
+							Expect(err).NotTo(HaveOccurred())
+							Expect(conf.Attachments).To(HaveLen(1))
+							Expect(conf.Attachments[0]).To(Equal(map[string]string{"containerID": runtimeConfig.ContainerID, "ifname": runtimeConfig.IfName}))
+						},
+					},
+					{
+						name: "DEL",
+						fn: func(entry noop_debug.CmdLogEntry) {
+							Expect(entry.CmdArgs.ContainerID).To(Equal(runtimeConfig.ContainerID))
+							Expect(entry.CmdArgs.IfName).To(Equal(runtimeConfig.IfName))
+						},
+					},
+					{
+						name: "GC",
+						fn: func(entry noop_debug.CmdLogEntry) {
+							var conf struct {
+								Attachments []map[string]string `json:"cni.dev/valid-attachments"`
+							}
+							err = json.Unmarshal(entry.CmdArgs.StdinData, &conf)
+							Expect(err).NotTo(HaveOccurred())
+							Expect(conf.Attachments).To(BeEmpty())
+						},
+					},
+				}
+				for i, c := range validations {
+					Expect(commands[i].Command).To(Equal(c.name))
+					c.fn(commands[i])
+				}
 			})
 		})
 	})

libcni/multierror.go

@@ -0,0 +1,58 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Copyright the CNI authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Adapted from errors/join.go from go 1.20
+// This package can be removed once the toolchain is updated to 1.20
+
+package libcni
+
+func joinErrors(errs ...error) error {
+	n := 0
+	for _, err := range errs {
+		if err != nil {
+			n++
+		}
+	}
+	if n == 0 {
+		return nil
+	}
+	e := &multiError{
+		errs: make([]error, 0, n),
+	}
+	for _, err := range errs {
+		if err != nil {
+			e.errs = append(e.errs, err)
+		}
+	}
+	return e
+}
+
+type multiError struct {
+	errs []error
+}
+
+func (e *multiError) Error() string {
+	var b []byte
+	for i, err := range e.errs {
+		if i > 0 {
+			b = append(b, '\n')
+		}
+		b = append(b, err.Error()...)
+	}
+	return string(b)
+}