Move CRI image service into a separate plugin

Signed-off-by: Maksym Pavlenko <pavlenko.maksym@gmail.com>
Signed-off-by: Abel Feng <fshb1988@gmail.com>

pkg/cri/server/base/cri_base.go

@@ -0,0 +1,121 @@
+/*
+   Copyright The containerd 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.
+*/
+
+package base
+
+import (
+	"flag"
+	"fmt"
+	"path/filepath"
+
+	"github.com/containerd/log"
+	imagespec "github.com/opencontainers/image-spec/specs-go/v1"
+	"k8s.io/klog/v2"
+
+	"github.com/containerd/containerd"
+	criconfig "github.com/containerd/containerd/pkg/cri/config"
+	"github.com/containerd/containerd/pkg/cri/constants"
+	"github.com/containerd/containerd/platforms"
+	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugin/registry"
+	"github.com/containerd/containerd/plugins"
+)
+
+// CRIBase contains common dependencies for CRI's runtime, image, and podsandbox services.
+type CRIBase struct {
+	// Config contains all configurations.
+	Config criconfig.Config
+	// Client is an instance of the containerd client
+	Client *containerd.Client
+}
+
+func init() {
+	config := criconfig.DefaultConfig()
+
+	// Base plugin that other CRI services depend on.
+	registry.Register(&plugin.Registration{
+		Type:   plugins.GRPCPlugin,
+		ID:     "cri",
+		Config: &config,
+		Requires: []plugin.Type{
+			plugins.EventPlugin,
+			plugins.ServicePlugin,
+			plugins.NRIApiPlugin,
+		},
+		InitFn: initCRIBase,
+	})
+}
+
+func initCRIBase(ic *plugin.InitContext) (interface{}, error) {
+	ic.Meta.Platforms = []imagespec.Platform{platforms.DefaultSpec()}
+	ic.Meta.Exports = map[string]string{"CRIVersion": constants.CRIVersion}
+	ctx := ic.Context
+	pluginConfig := ic.Config.(*criconfig.PluginConfig)
+	if err := criconfig.ValidatePluginConfig(ctx, pluginConfig); err != nil {
+		return nil, fmt.Errorf("invalid plugin config: %w", err)
+	}
+
+	c := criconfig.Config{
+		PluginConfig:       *pluginConfig,
+		ContainerdRootDir:  filepath.Dir(ic.Properties[plugins.PropertyRootDir]),
+		ContainerdEndpoint: ic.Properties[plugins.PropertyGRPCAddress],
+		RootDir:            ic.Properties[plugins.PropertyRootDir],
+		StateDir:           ic.Properties[plugins.PropertyStateDir],
+	}
+
+	log.G(ctx).Infof("Start cri plugin with config %+v", c)
+
+	if err := setGLogLevel(); err != nil {
+		return nil, fmt.Errorf("failed to set glog level: %w", err)
+	}
+
+	log.G(ctx).Info("Connect containerd service")
+	client, err := containerd.New(
+		"",
+		containerd.WithDefaultNamespace(constants.K8sContainerdNamespace),
+		containerd.WithDefaultPlatform(platforms.Default()),
+		containerd.WithInMemoryServices(ic),
+	)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create containerd client: %w", err)
+	}
+
+	return &CRIBase{
+		Config: c,
+		Client: client,
+	}, nil
+}
+
+// Set glog level.
+func setGLogLevel() error {
+	l := log.GetLevel()
+	fs := flag.NewFlagSet("klog", flag.PanicOnError)
+	klog.InitFlags(fs)
+	if err := fs.Set("logtostderr", "true"); err != nil {
+		return err
+	}
+	switch l {
+	case log.TraceLevel:
+		return fs.Set("v", "5")
+	case log.DebugLevel:
+		return fs.Set("v", "4")
+	case log.InfoLevel:
+		return fs.Set("v", "2")
+	default:
+		// glog doesn't support other filters. Defaults to v=0.
+	}
+	return nil
+}