Move services to plugins/services

Signed-off-by: Derek McGowan <derek@mcg.dev>

plugins/services/content/store.go

@@ -0,0 +1,78 @@
+/*
+   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 content
+
+import (
+	"context"
+
+	eventstypes "github.com/containerd/containerd/v2/api/events"
+	"github.com/containerd/containerd/v2/core/content"
+	"github.com/containerd/containerd/v2/core/metadata"
+	"github.com/containerd/containerd/v2/events"
+	"github.com/containerd/containerd/v2/plugins"
+	"github.com/containerd/containerd/v2/plugins/services"
+	"github.com/containerd/plugin"
+	"github.com/containerd/plugin/registry"
+	digest "github.com/opencontainers/go-digest"
+)
+
+// store wraps content.Store with proper event published.
+type store struct {
+	content.Store
+	publisher events.Publisher
+}
+
+func init() {
+	registry.Register(&plugin.Registration{
+		Type: plugins.ServicePlugin,
+		ID:   services.ContentService,
+		Requires: []plugin.Type{
+			plugins.EventPlugin,
+			plugins.MetadataPlugin,
+		},
+		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
+			m, err := ic.GetSingle(plugins.MetadataPlugin)
+			if err != nil {
+				return nil, err
+			}
+			ep, err := ic.GetSingle(plugins.EventPlugin)
+			if err != nil {
+				return nil, err
+			}
+
+			s, err := newContentStore(m.(*metadata.DB).ContentStore(), ep.(events.Publisher))
+			return s, err
+		},
+	})
+}
+
+func newContentStore(cs content.Store, publisher events.Publisher) (content.Store, error) {
+	return &store{
+		Store:     cs,
+		publisher: publisher,
+	}, nil
+}
+
+func (s *store) Delete(ctx context.Context, dgst digest.Digest) error {
+	if err := s.Store.Delete(ctx, dgst); err != nil {
+		return err
+	}
+	// TODO: Consider whether we should return error here.
+	return s.publisher.Publish(ctx, "/content/delete", &eventstypes.ContentDelete{
+		Digest: dgst.String(),
+	})
+}