Move metadata plugin registration to seperate package

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

cmd/containerd/builtins.go

@@ -22,6 +22,7 @@ import (
 	_ "github.com/containerd/containerd/events/plugin"
 	_ "github.com/containerd/containerd/gc/scheduler"
 	_ "github.com/containerd/containerd/leases/plugin"
+	_ "github.com/containerd/containerd/metadata/plugin"
 	_ "github.com/containerd/containerd/runtime/restart/monitor"
 	_ "github.com/containerd/containerd/runtime/v2"
 	_ "github.com/containerd/containerd/services/containers"

integration/build_local_containerd_helper_test.go

@@ -48,6 +48,7 @@ import (
 	_ "github.com/containerd/containerd/events/plugin"
 	_ "github.com/containerd/containerd/gc/scheduler"
 	_ "github.com/containerd/containerd/leases/plugin"
+	_ "github.com/containerd/containerd/metadata/plugin"
 	_ "github.com/containerd/containerd/runtime/v2"
 	_ "github.com/containerd/containerd/runtime/v2/runc/options"
 	_ "github.com/containerd/containerd/services/containers"

metadata/plugin/plugin.go

@@ -0,0 +1,179 @@
+/*
+   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 plugin
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/containerd/containerd/content"
+	"github.com/containerd/containerd/errdefs"
+	"github.com/containerd/containerd/log"
+	"github.com/containerd/containerd/metadata"
+	"github.com/containerd/containerd/pkg/timeout"
+	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/snapshots"
+	bolt "go.etcd.io/bbolt"
+)
+
+const (
+	boltOpenTimeout = "io.containerd.timeout.bolt.open"
+)
+
+func init() {
+	timeout.Set(boltOpenTimeout, 0) // set to 0 means to wait indefinitely for bolt.Open
+}
+
+// BoltConfig defines the configuration values for the bolt plugin, which is
+// loaded here, rather than back registered in the metadata package.
+type BoltConfig struct {
+	// ContentSharingPolicy sets the sharing policy for content between
+	// namespaces.
+	//
+	// The default mode "shared" will make blobs available in all
+	// namespaces once it is pulled into any namespace. The blob will be pulled
+	// into the namespace if a writer is opened with the "Expected" digest that
+	// is already present in the backend.
+	//
+	// The alternative mode, "isolated" requires that clients prove they have
+	// access to the content by providing all of the content to the ingest
+	// before the blob is added to the namespace.
+	//
+	// Both modes share backing data, while "shared" will reduce total
+	// bandwidth across namespaces, at the cost of allowing access to any blob
+	// just by knowing its digest.
+	ContentSharingPolicy string `toml:"content_sharing_policy"`
+}
+
+const (
+	// SharingPolicyShared represents the "shared" sharing policy
+	SharingPolicyShared = "shared"
+	// SharingPolicyIsolated represents the "isolated" sharing policy
+	SharingPolicyIsolated = "isolated"
+)
+
+// Validate validates if BoltConfig is valid
+func (bc *BoltConfig) Validate() error {
+	switch bc.ContentSharingPolicy {
+	case SharingPolicyShared, SharingPolicyIsolated:
+		return nil
+	default:
+		return fmt.Errorf("unknown policy: %s: %w", bc.ContentSharingPolicy, errdefs.ErrInvalidArgument)
+	}
+}
+
+func init() {
+	plugin.Register(&plugin.Registration{
+		Type: plugin.MetadataPlugin,
+		ID:   "bolt",
+		Requires: []plugin.Type{
+			plugin.ContentPlugin,
+			plugin.SnapshotPlugin,
+		},
+		Config: &BoltConfig{
+			ContentSharingPolicy: SharingPolicyShared,
+		},
+		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
+			if err := os.MkdirAll(ic.Root, 0711); err != nil {
+				return nil, err
+			}
+			cs, err := ic.Get(plugin.ContentPlugin)
+			if err != nil {
+				return nil, err
+			}
+
+			snapshottersRaw, err := ic.GetByType(plugin.SnapshotPlugin)
+			if err != nil {
+				return nil, err
+			}
+
+			snapshotters := make(map[string]snapshots.Snapshotter)
+			for name, sn := range snapshottersRaw {
+				sn, err := sn.Instance()
+				if err != nil {
+					if !plugin.IsSkipPlugin(err) {
+						log.G(ic.Context).WithError(err).
+							Warnf("could not use snapshotter %v in metadata plugin", name)
+					}
+					continue
+				}
+				snapshotters[name] = sn.(snapshots.Snapshotter)
+			}
+
+			shared := true
+			ic.Meta.Exports["policy"] = SharingPolicyShared
+			if cfg, ok := ic.Config.(*BoltConfig); ok {
+				if cfg.ContentSharingPolicy != "" {
+					if err := cfg.Validate(); err != nil {
+						return nil, err
+					}
+					if cfg.ContentSharingPolicy == SharingPolicyIsolated {
+						ic.Meta.Exports["policy"] = SharingPolicyIsolated
+						shared = false
+					}
+
+					log.G(ic.Context).WithField("policy", cfg.ContentSharingPolicy).Info("metadata content store policy set")
+				}
+			}
+
+			path := filepath.Join(ic.Root, "meta.db")
+			ic.Meta.Exports["path"] = path
+
+			options := *bolt.DefaultOptions
+			// Reading bbolt's freelist sometimes fails when the file has a data corruption.
+			// Disabling freelist sync reduces the chance of the breakage.
+			// https://github.com/etcd-io/bbolt/pull/1
+			// https://github.com/etcd-io/bbolt/pull/6
+			options.NoFreelistSync = true
+			// Without the timeout, bbolt.Open would block indefinitely due to flock(2).
+			options.Timeout = timeout.Get(boltOpenTimeout)
+
+			doneCh := make(chan struct{})
+			go func() {
+				t := time.NewTimer(10 * time.Second)
+				defer t.Stop()
+				select {
+				case <-t.C:
+					log.G(ic.Context).WithField("plugin", "bolt").Warn("waiting for response from boltdb open")
+				case <-doneCh:
+					return
+				}
+			}()
+			db, err := bolt.Open(path, 0644, &options)
+			close(doneCh)
+			if err != nil {
+				return nil, err
+			}
+
+			dbopts := []metadata.DBOpt{
+				//	metadata.WithEventsPublisher(ic.Events),
+			}
+
+			if !shared {
+				dbopts = append(dbopts, metadata.WithPolicyIsolated)
+			}
+
+			mdb := metadata.NewDB(db, cs.(content.Store), snapshotters, dbopts...)
+			if err := mdb.Init(ic.Context); err != nil {
+				return nil, err
+			}
+			return mdb, nil
+		},
+	})
+}

services/server/config/config.go

@@ -168,44 +168,6 @@ type ProxyPlugin struct {
 	Address string `toml:"address"`
 }
 
-// BoltConfig defines the configuration values for the bolt plugin, which is
-// loaded here, rather than back registered in the metadata package.
-type BoltConfig struct {
-	// ContentSharingPolicy sets the sharing policy for content between
-	// namespaces.
-	//
-	// The default mode "shared" will make blobs available in all
-	// namespaces once it is pulled into any namespace. The blob will be pulled
-	// into the namespace if a writer is opened with the "Expected" digest that
-	// is already present in the backend.
-	//
-	// The alternative mode, "isolated" requires that clients prove they have
-	// access to the content by providing all of the content to the ingest
-	// before the blob is added to the namespace.
-	//
-	// Both modes share backing data, while "shared" will reduce total
-	// bandwidth across namespaces, at the cost of allowing access to any blob
-	// just by knowing its digest.
-	ContentSharingPolicy string `toml:"content_sharing_policy"`
-}
-
-const (
-	// SharingPolicyShared represents the "shared" sharing policy
-	SharingPolicyShared = "shared"
-	// SharingPolicyIsolated represents the "isolated" sharing policy
-	SharingPolicyIsolated = "isolated"
-)
-
-// Validate validates if BoltConfig is valid
-func (bc *BoltConfig) Validate() error {
-	switch bc.ContentSharingPolicy {
-	case SharingPolicyShared, SharingPolicyIsolated:
-		return nil
-	default:
-		return fmt.Errorf("unknown policy: %s: %w", bc.ContentSharingPolicy, errdefs.ErrInvalidArgument)
-	}
-}
-
 // Decode unmarshals a plugin specific configuration by plugin id
 func (c *Config) Decode(p *plugin.Registration) (interface{}, error) {
 	id := p.URI()

services/server/server.go

@@ -36,26 +36,22 @@ import (
 
 	csapi "github.com/containerd/containerd/api/services/content/v1"
 	ssapi "github.com/containerd/containerd/api/services/snapshots/v1"
-	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/content/local"
 	csproxy "github.com/containerd/containerd/content/proxy"
 	"github.com/containerd/containerd/defaults"
 	"github.com/containerd/containerd/diff"
 	"github.com/containerd/containerd/events/exchange"
 	"github.com/containerd/containerd/log"
-	"github.com/containerd/containerd/metadata"
 	"github.com/containerd/containerd/pkg/dialer"
 	"github.com/containerd/containerd/pkg/timeout"
 	"github.com/containerd/containerd/plugin"
 	srvconfig "github.com/containerd/containerd/services/server/config"
-	"github.com/containerd/containerd/snapshots"
 	ssproxy "github.com/containerd/containerd/snapshots/proxy"
 	"github.com/containerd/containerd/sys"
 	"github.com/containerd/ttrpc"
 	metrics "github.com/docker/go-metrics"
 	grpc_middleware "github.com/grpc-ecosystem/go-grpc-middleware"
 	grpc_prometheus "github.com/grpc-ecosystem/go-grpc-prometheus"
-	bolt "go.etcd.io/bbolt"
 	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/backoff"
@@ -63,14 +59,6 @@ import (
 	"google.golang.org/grpc/credentials/insecure"
 )
 
-const (
-	boltOpenTimeout = "io.containerd.timeout.bolt.open"
-)
-
-func init() {
-	timeout.Set(boltOpenTimeout, 0) // set to 0 means to wait indefinitely for bolt.Open
-}
-
 // CreateTopLevelDirectories creates the top-level root and state directories.
 func CreateTopLevelDirectories(config *srvconfig.Config) error {
 	switch {
@@ -395,99 +383,6 @@ func LoadPlugins(ctx context.Context, config *srvconfig.Config) ([]*plugin.Regis
 			return local.NewStore(ic.Root)
 		},
 	})
-	plugin.Register(&plugin.Registration{
-		Type: plugin.MetadataPlugin,
-		ID:   "bolt",
-		Requires: []plugin.Type{
-			plugin.ContentPlugin,
-			plugin.SnapshotPlugin,
-		},
-		Config: &srvconfig.BoltConfig{
-			ContentSharingPolicy: srvconfig.SharingPolicyShared,
-		},
-		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			if err := os.MkdirAll(ic.Root, 0711); err != nil {
-				return nil, err
-			}
-			cs, err := ic.Get(plugin.ContentPlugin)
-			if err != nil {
-				return nil, err
-			}
-
-			snapshottersRaw, err := ic.GetByType(plugin.SnapshotPlugin)
-			if err != nil {
-				return nil, err
-			}
-
-			snapshotters := make(map[string]snapshots.Snapshotter)
-			for name, sn := range snapshottersRaw {
-				sn, err := sn.Instance()
-				if err != nil {
-					if !plugin.IsSkipPlugin(err) {
-						log.G(ic.Context).WithError(err).
-							Warnf("could not use snapshotter %v in metadata plugin", name)
-					}
-					continue
-				}
-				snapshotters[name] = sn.(snapshots.Snapshotter)
-			}
-
-			shared := true
-			ic.Meta.Exports["policy"] = srvconfig.SharingPolicyShared
-			if cfg, ok := ic.Config.(*srvconfig.BoltConfig); ok {
-				if cfg.ContentSharingPolicy != "" {
-					if err := cfg.Validate(); err != nil {
-						return nil, err
-					}
-					if cfg.ContentSharingPolicy == srvconfig.SharingPolicyIsolated {
-						ic.Meta.Exports["policy"] = srvconfig.SharingPolicyIsolated
-						shared = false
-					}
-
-					log.L.WithField("policy", cfg.ContentSharingPolicy).Info("metadata content store policy set")
-				}
-			}
-
-			path := filepath.Join(ic.Root, "meta.db")
-			ic.Meta.Exports["path"] = path
-
-			options := *bolt.DefaultOptions
-			// Reading bbolt's freelist sometimes fails when the file has a data corruption.
-			// Disabling freelist sync reduces the chance of the breakage.
-			// https://github.com/etcd-io/bbolt/pull/1
-			// https://github.com/etcd-io/bbolt/pull/6
-			options.NoFreelistSync = true
-			// Without the timeout, bbolt.Open would block indefinitely due to flock(2).
-			options.Timeout = timeout.Get(boltOpenTimeout)
-
-			doneCh := make(chan struct{})
-			go func() {
-				t := time.NewTimer(10 * time.Second)
-				defer t.Stop()
-				select {
-				case <-t.C:
-					log.G(ctx).WithField("plugin", "bolt").Warn("waiting for response from boltdb open")
-				case <-doneCh:
-					return
-				}
-			}()
-			db, err := bolt.Open(path, 0644, &options)
-			close(doneCh)
-			if err != nil {
-				return nil, err
-			}
-
-			var dbopts []metadata.DBOpt
-			if !shared {
-				dbopts = append(dbopts, metadata.WithPolicyIsolated)
-			}
-			mdb := metadata.NewDB(db, cs.(content.Store), snapshotters, dbopts...)
-			if err := mdb.Init(ic.Context); err != nil {
-				return nil, err
-			}
-			return mdb, nil
-		},
-	})
 
 	clients := &proxyClients{}
 	for name, pp := range config.ProxyPlugins {