Cleanup introspection interface

Split service proxy from service plugin.
Make introspection service easier for clients to use.
Update service proxy to support grpc and ttrpc.

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

client/client.go

@@ -31,7 +31,6 @@ import (
 	diffapi "github.com/containerd/containerd/v2/api/services/diff/v1"
 	eventsapi "github.com/containerd/containerd/v2/api/services/events/v1"
 	imagesapi "github.com/containerd/containerd/v2/api/services/images/v1"
-	introspectionapi "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	leasesapi "github.com/containerd/containerd/v2/api/services/leases/v1"
 	namespacesapi "github.com/containerd/containerd/v2/api/services/namespaces/v1"
 	sandboxsapi "github.com/containerd/containerd/v2/api/services/sandbox/v1"
@@ -44,6 +43,8 @@ import (
 	contentproxy "github.com/containerd/containerd/v2/core/content/proxy"
 	"github.com/containerd/containerd/v2/core/events"
 	"github.com/containerd/containerd/v2/core/images"
+	"github.com/containerd/containerd/v2/core/introspection"
+	introspectionproxy "github.com/containerd/containerd/v2/core/introspection/proxy"
 	"github.com/containerd/containerd/v2/core/leases"
 	leasesproxy "github.com/containerd/containerd/v2/core/leases/proxy"
 	"github.com/containerd/containerd/v2/core/remotes"
@@ -56,7 +57,6 @@ import (
 	"github.com/containerd/containerd/v2/pkg/dialer"
 	"github.com/containerd/containerd/v2/pkg/namespaces"
 	"github.com/containerd/containerd/v2/plugins"
-	"github.com/containerd/containerd/v2/plugins/services/introspection"
 	"github.com/containerd/containerd/v2/protobuf"
 	ptypes "github.com/containerd/containerd/v2/protobuf/types"
 	"github.com/containerd/errdefs"
@@ -681,7 +681,7 @@ func (c *Client) IntrospectionService() introspection.Service {
 	}
 	c.connMu.Lock()
 	defer c.connMu.Unlock()
-	return introspection.NewIntrospectionServiceFromClient(introspectionapi.NewIntrospectionClient(c.conn))
+	return introspectionproxy.NewIntrospectionProxy(c.conn)
 }
 
 // LeasesService returns the underlying Leases Client
@@ -785,7 +785,7 @@ func (c *Client) Server(ctx context.Context) (ServerInfo, error) {
 	}
 	c.connMu.Unlock()
 
-	response, err := c.IntrospectionService().Server(ctx, &ptypes.Empty{})
+	response, err := c.IntrospectionService().Server(ctx)
 	if err != nil {
 		return ServerInfo{}, err
 	}
@@ -831,7 +831,7 @@ func (c *Client) GetSnapshotterSupportedPlatforms(ctx context.Context, snapshott
 	filters := []string{fmt.Sprintf("type==%s, id==%s", plugins.SnapshotPlugin, snapshotterName)}
 	in := c.IntrospectionService()
 
-	resp, err := in.Plugins(ctx, filters)
+	resp, err := in.Plugins(ctx, filters...)
 	if err != nil {
 		return nil, err
 	}
@@ -862,7 +862,7 @@ func (c *Client) GetSnapshotterCapabilities(ctx context.Context, snapshotterName
 	filters := []string{fmt.Sprintf("type==%s, id==%s", plugins.SnapshotPlugin, snapshotterName)}
 	in := c.IntrospectionService()
 
-	resp, err := in.Plugins(ctx, filters)
+	resp, err := in.Plugins(ctx, filters...)
 	if err != nil {
 		return nil, err
 	}
@@ -903,20 +903,10 @@ func (c *Client) RuntimeInfo(ctx context.Context, runtimePath string, runtimeOpt
 			return nil, fmt.Errorf("failed to marshal %T: %w", runtimeOptions, err)
 		}
 	}
-	options, err := protobuf.MarshalAnyToProto(rr)
-	if err != nil {
-		return nil, fmt.Errorf("failed to marshal runtime requst: %w", err)
-	}
 
 	s := c.IntrospectionService()
 
-	req := &introspectionapi.PluginInfoRequest{
+	resp, err := s.PluginInfo(ctx, string(plugins.RuntimePluginV2), "task", rr)
-		Type:    string(plugins.RuntimePluginV2),
-		ID:      "task",
-		Options: options,
-	}
-
-	resp, err := s.PluginInfo(ctx, req)
 	if err != nil {
 		return nil, err
 	}

client/install.go

@@ -112,8 +112,7 @@ func (c *Client) getInstallPath(ctx context.Context, config InstallConfig) (stri
 	if config.Path != "" {
 		return config.Path, nil
 	}
-	filters := []string{"id==opt"}
+	resp, err := c.IntrospectionService().Plugins(ctx, "id==opt")
-	resp, err := c.IntrospectionService().Plugins(ctx, filters)
 	if err != nil {
 		return "", err
 	}

client/services.go

@@ -22,19 +22,18 @@ import (
 	containersapi "github.com/containerd/containerd/v2/api/services/containers/v1"
 	"github.com/containerd/containerd/v2/api/services/diff/v1"
 	imagesapi "github.com/containerd/containerd/v2/api/services/images/v1"
-	introspectionapi "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	namespacesapi "github.com/containerd/containerd/v2/api/services/namespaces/v1"
 	"github.com/containerd/containerd/v2/api/services/tasks/v1"
 	"github.com/containerd/containerd/v2/core/containers"
 	"github.com/containerd/containerd/v2/core/content"
 	"github.com/containerd/containerd/v2/core/images"
+	"github.com/containerd/containerd/v2/core/introspection"
 	"github.com/containerd/containerd/v2/core/leases"
 	"github.com/containerd/containerd/v2/core/sandbox"
 	"github.com/containerd/containerd/v2/core/snapshots"
 	"github.com/containerd/containerd/v2/pkg/namespaces"
 	"github.com/containerd/containerd/v2/plugins"
 	srv "github.com/containerd/containerd/v2/plugins/services"
-	"github.com/containerd/containerd/v2/plugins/services/introspection"
 	"github.com/containerd/plugin"
 )
 
@@ -150,13 +149,6 @@ func WithLeasesService(leasesService leases.Manager) ServicesOpt {
 	}
 }
 
-// WithIntrospectionClient sets the introspection service using an introspection client.
-func WithIntrospectionClient(in introspectionapi.IntrospectionClient) ServicesOpt {
-	return func(s *services) {
-		s.introspectionService = introspection.NewIntrospectionServiceFromClient(in)
-	}
-}
-
 // WithIntrospectionService sets the introspection service.
 func WithIntrospectionService(in introspection.Service) ServicesOpt {
 	return func(s *services) {
@@ -221,7 +213,7 @@ func WithInMemoryServices(ic *plugin.InitContext) Opt {
 				return WithNamespaceClient(s.(namespacesapi.NamespacesClient))
 			},
 			srv.IntrospectionService: func(s interface{}) ServicesOpt {
-				return WithIntrospectionClient(s.(introspectionapi.IntrospectionClient))
+				return WithIntrospectionService(s.(introspection.Service))
 			},
 		} {
 			i := plugins[s]

cmd/ctr/commands/client.go

@@ -24,7 +24,6 @@ import (
 	containerd "github.com/containerd/containerd/v2/client"
 	"github.com/containerd/containerd/v2/pkg/epoch"
 	"github.com/containerd/containerd/v2/pkg/namespaces"
-	ptypes "github.com/containerd/containerd/v2/protobuf/types"
 	"github.com/containerd/log"
 	"github.com/urfave/cli/v2"
 )
@@ -73,7 +72,7 @@ func NewClient(context *cli.Context, opts ...containerd.Opt) (*containerd.Client
 		}
 	}
 	if !suppressDeprecationWarnings {
-		resp, err := client.IntrospectionService().Server(ctx, &ptypes.Empty{})
+		resp, err := client.IntrospectionService().Server(ctx)
 		if err != nil {
 			log.L.WithError(err).Warn("Failed to check deprecations")
 		} else {

cmd/ctr/commands/deprecations/deprecations.go

@@ -27,7 +27,6 @@ import (
 	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	"github.com/containerd/containerd/v2/cmd/ctr/commands"
 	"github.com/containerd/containerd/v2/protobuf"
-	ptypes "github.com/containerd/containerd/v2/protobuf/types"
 )
 
 // Command is the parent for all commands under "deprecations"
@@ -56,7 +55,7 @@ var listCommand = &cli.Command{
 		}
 		defer cancel()
 
-		resp, err := client.IntrospectionService().Server(ctx, &ptypes.Empty{})
+		resp, err := client.IntrospectionService().Server(ctx)
 		if err != nil {
 			return err
 		}

cmd/ctr/commands/info/info.go

@@ -19,7 +19,6 @@ package info
 import (
 	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	"github.com/containerd/containerd/v2/cmd/ctr/commands"
-	ptypes "github.com/containerd/containerd/v2/protobuf/types"
 	"github.com/urfave/cli/v2"
 )
 
@@ -38,7 +37,7 @@ var Command = &cli.Command{
 		}
 		defer cancel()
 		var info Info
-		info.Server, err = client.IntrospectionService().Server(ctx, &ptypes.Empty{})
+		info.Server, err = client.IntrospectionService().Server(ctx)
 		if err != nil {
 			return err
 		}

cmd/ctr/commands/plugins/plugins.go

@@ -71,7 +71,7 @@ var listCommand = &cli.Command{
 		}
 		defer cancel()
 		ps := client.IntrospectionService()
-		response, err := ps.Plugins(ctx, context.Args().Slice())
+		response, err := ps.Plugins(ctx, context.Args().Slice()...)
 		if err != nil {
 			return err
 		}

core/introspection/introspection.go

@@ -0,0 +1,30 @@
+/*
+   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 introspection
+
+import (
+	context "context"
+
+	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
+)
+
+// Service defines the introspection service interface
+type Service interface {
+	Plugins(context.Context, ...string) (*api.PluginsResponse, error)
+	Server(context.Context) (*api.ServerResponse, error)
+	PluginInfo(context.Context, string, string, any) (*api.PluginInfoResponse, error)
+}

core/introspection/proxy/remote.go

@@ -0,0 +1,108 @@
+/*
+   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 introspectionproxy
+
+import (
+	"context"
+	"fmt"
+
+	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
+	"github.com/containerd/containerd/v2/core/introspection"
+	"github.com/containerd/containerd/v2/protobuf"
+	"github.com/containerd/errdefs"
+	"github.com/containerd/log"
+	"github.com/containerd/ttrpc"
+	"google.golang.org/grpc"
+	"google.golang.org/protobuf/types/known/anypb"
+	"google.golang.org/protobuf/types/known/emptypb"
+)
+
+var _ = (introspection.Service)(&introspectionRemote{})
+
+// NewIntrospectionServiceFromClient creates a new introspection service from an API client
+func NewIntrospectionProxy(client any) introspection.Service {
+	switch c := client.(type) {
+	case api.IntrospectionClient:
+		return &introspectionRemote{client: convertIntrospection{c}}
+	case api.TTRPCIntrospectionService:
+		return &introspectionRemote{client: c}
+	case grpc.ClientConnInterface:
+		return &introspectionRemote{client: convertIntrospection{api.NewIntrospectionClient(c)}}
+	case *ttrpc.Client:
+		return &introspectionRemote{client: api.NewTTRPCIntrospectionClient(c)}
+	default:
+		panic(fmt.Errorf("unsupported introspection client %T: %w", client, errdefs.ErrNotImplemented))
+	}
+}
+
+type introspectionRemote struct {
+	client api.TTRPCIntrospectionService
+}
+
+func (i *introspectionRemote) Plugins(ctx context.Context, filters ...string) (*api.PluginsResponse, error) {
+	log.G(ctx).WithField("filters", filters).Debug("remote introspection plugin filters")
+	resp, err := i.client.Plugins(ctx, &api.PluginsRequest{
+		Filters: filters,
+	})
+
+	if err != nil {
+		return nil, errdefs.FromGRPC(err)
+	}
+
+	return resp, nil
+}
+
+func (i *introspectionRemote) Server(ctx context.Context) (*api.ServerResponse, error) {
+	resp, err := i.client.Server(ctx, &emptypb.Empty{})
+
+	if err != nil {
+		return nil, errdefs.FromGRPC(err)
+	}
+
+	return resp, nil
+}
+
+func (i *introspectionRemote) PluginInfo(ctx context.Context, pluginType, id string, options any) (resp *api.PluginInfoResponse, err error) {
+	var optionsPB *anypb.Any
+	if options != nil {
+		optionsPB, err = protobuf.MarshalAnyToProto(options)
+		if err != nil {
+			return nil, fmt.Errorf("failed to marshal runtime requst: %w", err)
+		}
+	}
+	resp, err = i.client.PluginInfo(ctx, &api.PluginInfoRequest{
+		Type:    pluginType,
+		ID:      id,
+		Options: optionsPB,
+	})
+
+	return resp, errdefs.FromGRPC(err)
+}
+
+type convertIntrospection struct {
+	client api.IntrospectionClient
+}
+
+func (c convertIntrospection) Plugins(ctx context.Context, req *api.PluginsRequest) (*api.PluginsResponse, error) {
+	return c.client.Plugins(ctx, req)
+}
+func (c convertIntrospection) Server(ctx context.Context, in *emptypb.Empty) (*api.ServerResponse, error) {
+	return c.client.Server(ctx, in)
+}
+func (c convertIntrospection) PluginInfo(ctx context.Context, req *api.PluginInfoRequest) (*api.PluginInfoResponse, error) {
+	return c.client.PluginInfo(ctx, req)
+}

internal/cri/server/service.go

@@ -34,9 +34,9 @@ import (
 	runtime "k8s.io/cri-api/pkg/apis/runtime/v1"
 	"k8s.io/kubelet/pkg/cri/streaming"
 
-	introspectionapi "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	apitypes "github.com/containerd/containerd/v2/api/types"
 	containerd "github.com/containerd/containerd/v2/client"
+	"github.com/containerd/containerd/v2/core/introspection"
 	_ "github.com/containerd/containerd/v2/core/runtime" // for typeurl init
 	"github.com/containerd/containerd/v2/core/sandbox"
 	"github.com/containerd/containerd/v2/internal/cri/config"
@@ -54,7 +54,6 @@ import (
 	"github.com/containerd/containerd/v2/pkg/oci"
 	osinterface "github.com/containerd/containerd/v2/pkg/os"
 	"github.com/containerd/containerd/v2/plugins"
-	"github.com/containerd/containerd/v2/plugins/services/introspection"
 	"github.com/containerd/containerd/v2/protobuf"
 )
 
@@ -407,10 +406,7 @@ func introspectRuntimeFeatures(ctx context.Context, intro introspection.Service,
 			plugins.RuntimeRuncV2, r.Type)
 		// For other runtimes, protobuf.MarshalAnyToProto will cause nil panic during typeurl dereference
 	}
-	infoReq := &introspectionapi.PluginInfoRequest{
+
-		Type: string(plugins.RuntimePluginV2), // "io.containerd.runtime.v2"
-		ID:   "task",
-	}
 	rr := &apitypes.RuntimeRequest{
 		RuntimePath: r.Type, // "io.containerd.runc.v2"
 	}
@@ -425,11 +421,8 @@ func introspectRuntimeFeatures(ctx context.Context, intro introspection.Service,
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal %T: %w", options, err)
 	}
-	infoReq.Options, err = protobuf.MarshalAnyToProto(rr)
+
-	if err != nil {
+	infoResp, err := intro.PluginInfo(ctx, string(plugins.RuntimePluginV2), "task", rr)
-		return nil, fmt.Errorf("failed to marshal %T: %w", rr, err)
-	}
-	infoResp, err := intro.PluginInfo(ctx, infoReq)
 	if err != nil {
 		return nil, fmt.Errorf("failed to call PluginInfo: %w", err)
 	}

internal/cri/server/status.go

@@ -23,7 +23,6 @@ import (
 	goruntime "runtime"
 
 	"github.com/containerd/containerd/v2/api/services/introspection/v1"
-	ptypes "github.com/containerd/containerd/v2/protobuf/types"
 	"github.com/containerd/log"
 	runtime "k8s.io/cri-api/pkg/apis/runtime/v1"
 )
@@ -97,7 +96,7 @@ func (c *criService) Status(ctx context.Context, r *runtime.StatusRequest) (*run
 		}
 		resp.Info["lastCNILoadStatus"] = defaultStatus
 	}
-	intro, err := c.client.IntrospectionService().Server(ctx, &ptypes.Empty{})
+	intro, err := c.client.IntrospectionService().Server(ctx)
 	if err != nil {
 		return nil, err
 	}

plugins/services/introspection/introspection.go

@@ -1,77 +0,0 @@
-/*
-   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 introspection
-
-import (
-	context "context"
-
-	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
-	ptypes "github.com/containerd/containerd/v2/protobuf/types"
-	"github.com/containerd/errdefs"
-	"github.com/containerd/log"
-)
-
-// Service defines the introspection service interface
-type Service interface {
-	Plugins(context.Context, []string) (*api.PluginsResponse, error)
-	Server(context.Context, *ptypes.Empty) (*api.ServerResponse, error)
-	PluginInfo(ctx context.Context, in *api.PluginInfoRequest) (*api.PluginInfoResponse, error)
-}
-
-type introspectionRemote struct {
-	client api.IntrospectionClient
-}
-
-var _ = (Service)(&introspectionRemote{})
-
-// NewIntrospectionServiceFromClient creates a new introspection service from an API client
-func NewIntrospectionServiceFromClient(c api.IntrospectionClient) Service {
-	return &introspectionRemote{client: c}
-}
-
-func (i *introspectionRemote) Plugins(ctx context.Context, filters []string) (*api.PluginsResponse, error) {
-	log.G(ctx).WithField("filters", filters).Debug("remote introspection plugin filters")
-	resp, err := i.client.Plugins(ctx, &api.PluginsRequest{
-		Filters: filters,
-	})
-
-	if err != nil {
-		return nil, errdefs.FromGRPC(err)
-	}
-
-	return resp, nil
-}
-
-func (i *introspectionRemote) Server(ctx context.Context, in *ptypes.Empty) (*api.ServerResponse, error) {
-	resp, err := i.client.Server(ctx, in)
-
-	if err != nil {
-		return nil, errdefs.FromGRPC(err)
-	}
-
-	return resp, nil
-}
-
-func (i *introspectionRemote) PluginInfo(ctx context.Context, in *api.PluginInfoRequest) (*api.PluginInfoResponse, error) {
-	resp, err := i.client.PluginInfo(ctx, in)
-
-	if err != nil {
-		return nil, errdefs.FromGRPC(err)
-	}
-
-	return resp, nil
-}

plugins/services/introspection/local.go

@@ -28,11 +28,11 @@ import (
 	"github.com/google/uuid"
 	"google.golang.org/genproto/googleapis/rpc/code"
 	rpc "google.golang.org/genproto/googleapis/rpc/status"
-	"google.golang.org/grpc"
 	"google.golang.org/grpc/status"
 
 	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
 	"github.com/containerd/containerd/v2/api/types"
+	"github.com/containerd/containerd/v2/core/introspection"
 	"github.com/containerd/containerd/v2/pkg/filters"
 	"github.com/containerd/containerd/v2/plugins"
 	"github.com/containerd/containerd/v2/plugins/services"
@@ -80,7 +80,7 @@ type Local struct {
 	warningClient warning.Service
 }
 
-var _ = (api.IntrospectionClient)(&Local{})
+var _ = (introspection.Service)(&Local{})
 
 // UpdateLocal updates the local introspection service
 func (l *Local) UpdateLocal(root string) {
@@ -90,10 +90,10 @@ func (l *Local) UpdateLocal(root string) {
 }
 
 // Plugins returns the locally defined plugins
-func (l *Local) Plugins(ctx context.Context, req *api.PluginsRequest, _ ...grpc.CallOption) (*api.PluginsResponse, error) {
+func (l *Local) Plugins(ctx context.Context, fs ...string) (*api.PluginsResponse, error) {
-	filter, err := filters.ParseAll(req.Filters...)
+	filter, err := filters.ParseAll(fs...)
 	if err != nil {
-		return nil, errdefs.ToGRPCf(errdefs.ErrInvalidArgument, err.Error())
+		return nil, fmt.Errorf("%w: %w", errdefs.ErrInvalidArgument, err)
 	}
 
 	var plugins []*api.Plugin
@@ -121,17 +121,17 @@ func (l *Local) getPlugins() []*api.Plugin {
 }
 
 // Server returns the local server information
-func (l *Local) Server(ctx context.Context, _ *ptypes.Empty, _ ...grpc.CallOption) (*api.ServerResponse, error) {
+func (l *Local) Server(ctx context.Context) (*api.ServerResponse, error) {
 	u, err := l.getUUID()
 	if err != nil {
-		return nil, errdefs.ToGRPC(err)
+		return nil, err
 	}
 	pid := os.Getpid()
 	var pidns uint64
 	if runtime.GOOS == "linux" {
 		pidns, err = statPIDNS(pid)
 		if err != nil {
-			return nil, errdefs.ToGRPC(err)
+			return nil, err
 		}
 	}
 	return &api.ServerResponse{
@@ -278,11 +278,10 @@ type pluginInfoProvider interface {
 	PluginInfo(context.Context, interface{}) (interface{}, error)
 }
 
-func (l *Local) PluginInfo(ctx context.Context, req *api.PluginInfoRequest, _ ...grpc.CallOption) (*api.PluginInfoResponse, error) {
+func (l *Local) PluginInfo(ctx context.Context, pluginType, id string, options any) (*api.PluginInfoResponse, error) {
-	p := l.plugins.Get(plugin.Type(req.Type), req.ID)
+	p := l.plugins.Get(plugin.Type(pluginType), id)
 	if p == nil {
-		err := fmt.Errorf("plugin %s.%s not found: %w", req.Type, req.ID, errdefs.ErrNotFound)
+		return nil, fmt.Errorf("plugin %s.%s not found: %w", pluginType, id, errdefs.ErrNotFound)
-		return nil, errdefs.ToGRPC(err)
 	}
 
 	resp := &api.PluginInfoResponse{
@@ -290,35 +289,26 @@ func (l *Local) PluginInfo(ctx context.Context, req *api.PluginInfoRequest, _ ..
 	}
 
 	// Request additional info from plugin instance
-	if req.Options != nil {
+	if options != nil {
 		if p.Err() != nil {
-			err := fmt.Errorf("cannot get extra info, plugin not successfully loaded: %w", errdefs.ErrFailedPrecondition)
+			return resp, fmt.Errorf("cannot get extra info, plugin not successfully loaded: %w", errdefs.ErrFailedPrecondition)
-			return resp, errdefs.ToGRPC(err)
 		}
 		inst, err := p.Instance()
 		if err != nil {
-			err := fmt.Errorf("failed to get plugin instance: %w", errdefs.ErrFailedPrecondition)
+			return resp, fmt.Errorf("failed to get plugin instance: %w", errdefs.ErrFailedPrecondition)
-			return resp, errdefs.ToGRPC(err)
 		}
 		pi, ok := inst.(pluginInfoProvider)
 		if !ok {
-			err := fmt.Errorf("plugin does not provided extra information: %w", errdefs.ErrNotImplemented)
+			return resp, fmt.Errorf("plugin does not provided extra information: %w", errdefs.ErrNotImplemented)
-			return resp, errdefs.ToGRPC(err)
 		}
 
-		options, err := typeurl.UnmarshalAny(req.Options)
-		if err != nil {
-			err = fmt.Errorf("failed to unmarshal plugin info Options: %w", err)
-			return resp, errdefs.ToGRPC(err)
-		}
 		info, err := pi.PluginInfo(ctx, options)
 		if err != nil {
 			return resp, errdefs.ToGRPC(err)
 		}
 		ai, err := typeurl.MarshalAny(info)
 		if err != nil {
-			err = fmt.Errorf("failed to marshal plugin info: %w", err)
+			return resp, fmt.Errorf("failed to marshal plugin info: %w", err)
-			return resp, errdefs.ToGRPC(err)
 		}
 		resp.Extra = &ptypes.Any{
 			TypeUrl: ai.GetTypeUrl(),

plugins/services/introspection/service.go

@@ -19,13 +19,17 @@ package introspection
 import (
 	context "context"
 	"errors"
+	"fmt"
 
 	api "github.com/containerd/containerd/v2/api/services/introspection/v1"
+	"github.com/containerd/containerd/v2/core/introspection"
 	"github.com/containerd/containerd/v2/plugins"
 	"github.com/containerd/containerd/v2/plugins/services"
 	ptypes "github.com/containerd/containerd/v2/protobuf/types"
+	"github.com/containerd/errdefs"
 	"github.com/containerd/plugin"
 	"github.com/containerd/plugin/registry"
+	"github.com/containerd/typeurl/v2"
 	"google.golang.org/grpc"
 )
 
@@ -54,7 +58,7 @@ func init() {
 }
 
 type server struct {
-	local api.IntrospectionClient
+	local introspection.Service
 	api.UnimplementedIntrospectionServer
 }
 
@@ -65,14 +69,25 @@ func (s *server) Register(server *grpc.Server) error {
 	return nil
 }
 
-func (s *server) Plugins(ctx context.Context, req *api.PluginsRequest) (*api.PluginsResponse, error) {
+func (s *server) Plugins(ctx context.Context, req *api.PluginsRequest) (resp *api.PluginsResponse, err error) {
-	return s.local.Plugins(ctx, req)
+	resp, err = s.local.Plugins(ctx, req.Filters...)
+	return resp, errdefs.ToGRPC(err)
 }
 
-func (s *server) Server(ctx context.Context, empty *ptypes.Empty) (*api.ServerResponse, error) {
+func (s *server) Server(ctx context.Context, _ *ptypes.Empty) (resp *api.ServerResponse, err error) {
-	return s.local.Server(ctx, empty)
+	resp, err = s.local.Server(ctx)
+	return resp, errdefs.ToGRPC(err)
 }
 
-func (s *server) PluginInfo(ctx context.Context, req *api.PluginInfoRequest) (*api.PluginInfoResponse, error) {
+func (s *server) PluginInfo(ctx context.Context, req *api.PluginInfoRequest) (resp *api.PluginInfoResponse, err error) {
-	return s.local.PluginInfo(ctx, req)
+	var options any
+	if req.Options != nil {
+		options, err = typeurl.UnmarshalAny(req.Options)
+		if err != nil {
+			return resp, errdefs.ToGRPC(fmt.Errorf("failed to unmarshal plugin info Options: %w", err))
+		}
+	}
+
+	resp, err = s.local.PluginInfo(ctx, req.Type, req.ID, options)
+	return resp, errdefs.ToGRPC(err)
 }