Move plugin type definitions to containerd plugins package

The plugins packages defines the plugins used by containerd.
Move all the types and properties to this package.

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

plugins/imageverifier/plugin.go

@@ -22,12 +22,13 @@ import (
 	"github.com/containerd/containerd/pkg/imageverifier/bindir"
 	"github.com/containerd/containerd/pkg/tomlext"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugins"
 )
 
 // Register default image verifier service plugin
 func init() {
 	plugin.Register(&plugin.Registration{
-		Type:   plugin.ImageVerifierPlugin,
+		Type:   plugins.ImageVerifierPlugin,
 		ID:     "bindir",
 		Config: defaultConfig(),
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {

plugins/sandbox/controller.go

@@ -29,6 +29,7 @@ import (
 	"github.com/containerd/containerd/mount"
 	"github.com/containerd/containerd/platforms"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugins"
 	"github.com/containerd/containerd/runtime"
 	v2 "github.com/containerd/containerd/runtime/v2"
 	"github.com/containerd/containerd/sandbox"
@@ -39,25 +40,25 @@ import (
 
 func init() {
 	plugin.Register(&plugin.Registration{
-		Type: plugin.SandboxControllerPlugin,
+		Type: plugins.SandboxControllerPlugin,
 		ID:   "local",
 		Requires: []plugin.Type{
-			plugin.RuntimePluginV2,
-			plugin.EventPlugin,
-			plugin.SandboxStorePlugin,
+			plugins.RuntimePluginV2,
+			plugins.EventPlugin,
+			plugins.SandboxStorePlugin,
 		},
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			shimPlugin, err := ic.GetByID(plugin.RuntimePluginV2, "shim")
+			shimPlugin, err := ic.GetByID(plugins.RuntimePluginV2, "shim")
 			if err != nil {
 				return nil, err
 			}
 
-			exchangePlugin, err := ic.GetByID(plugin.EventPlugin, "exchange")
+			exchangePlugin, err := ic.GetByID(plugins.EventPlugin, "exchange")
 			if err != nil {
 				return nil, err
 			}
 
-			sbPlugin, err := ic.GetByID(plugin.SandboxStorePlugin, "local")
+			sbPlugin, err := ic.GetByID(plugins.SandboxStorePlugin, "local")
 			if err != nil {
 				return nil, err
 			}

plugins/sandbox/store.go

@@ -19,17 +19,18 @@ package sandbox
 import (
 	"github.com/containerd/containerd/metadata"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugins"
 )
 
 func init() {
 	plugin.Register(&plugin.Registration{
-		Type: plugin.SandboxStorePlugin,
+		Type: plugins.SandboxStorePlugin,
 		ID:   "local",
 		Requires: []plugin.Type{
-			plugin.MetadataPlugin,
+			plugins.MetadataPlugin,
 		},
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			m, err := ic.Get(plugin.MetadataPlugin)
+			m, err := ic.Get(plugins.MetadataPlugin)
 			if err != nil {
 				return nil, err
 			}

plugins/streaming/manager.go

@@ -28,17 +28,18 @@ import (
 	"github.com/containerd/containerd/namespaces"
 	"github.com/containerd/containerd/pkg/streaming"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugins"
 )
 
 func init() {
 	plugin.Register(&plugin.Registration{
-		Type: plugin.StreamingPlugin,
+		Type: plugins.StreamingPlugin,
 		ID:   "manager",
 		Requires: []plugin.Type{
-			plugin.MetadataPlugin,
+			plugins.MetadataPlugin,
 		},
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
-			md, err := ic.Get(plugin.MetadataPlugin)
+			md, err := ic.Get(plugins.MetadataPlugin)
 			if err != nil {
 				return nil, err
 			}

plugins/transfer/plugin.go

@@ -29,6 +29,7 @@ import (
 	"github.com/containerd/containerd/pkg/unpack"
 	"github.com/containerd/containerd/platforms"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/plugins"
 	"github.com/containerd/log"
 
 	// Load packages with type registrations
@@ -40,29 +41,29 @@ import (
 // Register local transfer service plugin
 func init() {
 	plugin.Register(&plugin.Registration{
-		Type: plugin.TransferPlugin,
+		Type: plugins.TransferPlugin,
 		ID:   "local",
 		Requires: []plugin.Type{
-			plugin.LeasePlugin,
-			plugin.MetadataPlugin,
-			plugin.DiffPlugin,
-			plugin.ImageVerifierPlugin,
+			plugins.LeasePlugin,
+			plugins.MetadataPlugin,
+			plugins.DiffPlugin,
+			plugins.ImageVerifierPlugin,
 		},
 		Config: defaultConfig(),
 		InitFn: func(ic *plugin.InitContext) (interface{}, error) {
 			config := ic.Config.(*transferConfig)
-			m, err := ic.Get(plugin.MetadataPlugin)
+			m, err := ic.Get(plugins.MetadataPlugin)
 			if err != nil {
 				return nil, err
 			}
 			ms := m.(*metadata.DB)
-			l, err := ic.Get(plugin.LeasePlugin)
+			l, err := ic.Get(plugins.LeasePlugin)
 			if err != nil {
 				return nil, err
 			}
 
 			vfs := make(map[string]imageverifier.ImageVerifier)
-			vps, err := ic.GetByType(plugin.ImageVerifierPlugin)
+			vps, err := ic.GetByType(plugins.ImageVerifierPlugin)
 			if err != nil {
 				return nil, err
 			}
@@ -82,7 +83,7 @@ func init() {
 			for _, uc := range config.UnpackConfiguration {
 				p, err := platforms.Parse(uc.Platform)
 				if err != nil {
-					return nil, fmt.Errorf("%s: platform configuration %v invalid", plugin.TransferPlugin, uc.Platform)
+					return nil, fmt.Errorf("%s: platform configuration %v invalid", plugins.TransferPlugin, uc.Platform)
 				}
 
 				sn := ms.Snapshotter(uc.Snapshotter)
@@ -90,7 +91,7 @@ func init() {
 					return nil, fmt.Errorf("snapshotter %q not found: %w", uc.Snapshotter, errdefs.ErrNotFound)
 				}
 
-				diffPlugins, err := ic.GetByType(plugin.DiffPlugin)
+				diffPlugins, err := ic.GetByType(plugins.DiffPlugin)
 				if err != nil {
 					return nil, fmt.Errorf("error loading diff plugins: %w", err)
 				}

plugins/types.go

@@ -0,0 +1,84 @@
+/*
+   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.
+*/
+
+// plugins package stores all the plugin types used by containerd internally.
+//
+// External plugins should copy from these types and avoid importing this
+// package.
+package plugins
+
+import "github.com/containerd/containerd/plugin"
+
+const (
+	// InternalPlugin implements an internal plugin to containerd
+	InternalPlugin plugin.Type = "io.containerd.internal.v1"
+	// RuntimePlugin implements a runtime
+	RuntimePlugin plugin.Type = "io.containerd.runtime.v1"
+	// RuntimePluginV2 implements a runtime v2
+	RuntimePluginV2 plugin.Type = "io.containerd.runtime.v2"
+	// ServicePlugin implements a internal service
+	ServicePlugin plugin.Type = "io.containerd.service.v1"
+	// GRPCPlugin implements a grpc service
+	GRPCPlugin plugin.Type = "io.containerd.grpc.v1"
+	// TTRPCPlugin implements a ttrpc shim service
+	TTRPCPlugin plugin.Type = "io.containerd.ttrpc.v1"
+	// SnapshotPlugin implements a snapshotter
+	SnapshotPlugin plugin.Type = "io.containerd.snapshotter.v1"
+	// TaskMonitorPlugin implements a task monitor
+	TaskMonitorPlugin plugin.Type = "io.containerd.monitor.v1"
+	// DiffPlugin implements a differ
+	DiffPlugin plugin.Type = "io.containerd.differ.v1"
+	// MetadataPlugin implements a metadata store
+	MetadataPlugin plugin.Type = "io.containerd.metadata.v1"
+	// ContentPlugin implements a content store
+	ContentPlugin plugin.Type = "io.containerd.content.v1"
+	// GCPlugin implements garbage collection policy
+	GCPlugin plugin.Type = "io.containerd.gc.v1"
+	// EventPlugin implements event handling
+	EventPlugin plugin.Type = "io.containerd.event.v1"
+	// LeasePlugin implements lease manager
+	LeasePlugin plugin.Type = "io.containerd.lease.v1"
+	// StreamingPlugin implements a stream manager
+	StreamingPlugin plugin.Type = "io.containerd.streaming.v1"
+	// TracingProcessorPlugin implements a open telemetry span processor
+	TracingProcessorPlugin plugin.Type = "io.containerd.tracing.processor.v1"
+	// NRIApiPlugin implements the NRI adaptation interface for containerd.
+	NRIApiPlugin plugin.Type = "io.containerd.nri.v1"
+	// TransferPlugin implements a transfer service
+	TransferPlugin plugin.Type = "io.containerd.transfer.v1"
+	// SandboxStorePlugin implements a sandbox store
+	SandboxStorePlugin plugin.Type = "io.containerd.sandbox.store.v1"
+	// SandboxControllerPlugin implements a sandbox controller
+	SandboxControllerPlugin plugin.Type = "io.containerd.sandbox.controller.v1"
+	// ImageVerifierPlugin implements an image verifier service
+	ImageVerifierPlugin plugin.Type = "io.containerd.image-verifier.v1"
+)
+
+const (
+	// RuntimeRuncV2 is the runc runtime that supports multiple containers per shim
+	RuntimeRuncV2 = "io.containerd.runc.v2"
+)
+
+const (
+	// PropertyRootDir sets the root directory property for a plugin
+	PropertyRootDir = "io.containerd.plugin.root"
+	// PropertyStateDir sets the state directory property for a plugin
+	PropertyStateDir = "io.containerd.plugin.state"
+	// PropertyGRPCAddress is the grpc address used for client connections to containerd
+	PropertyGRPCAddress = "io.containerd.plugin.grpc.address"
+	// PropertyGRPCAddress is the ttrpc address used for client connections to containerd
+	PropertyTTRPCAddress = "io.containerd.plugin.ttrpc.address"
+)