Merge pull request #9214 from dmcgowan/generalize-plugin-library

Generalize plugin library

Author: AkihiroSuda

context.go

@@ -19,20 +19,15 @@ package plugin
 import (
 	"context"
 	"fmt"
-	"path/filepath"
 
-	"github.com/containerd/containerd/errdefs"
-	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	imagespec "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
 // InitContext is used for plugin initialization
 type InitContext struct {
 	Context           context.Context
-	Root              string
-	State             string
+	Properties        map[string]string
 	Config            interface{}
-	Address           string
-	TTRPCAddress      string
 	RegisterReadiness func() func()
 
 	// Meta is metadata plugins can fill in at init
@@ -42,11 +37,13 @@ type InitContext struct {
 }
 
 // NewContext returns a new plugin InitContext
-func NewContext(ctx context.Context, r *Registration, plugins *Set, root, state string) *InitContext {
+func NewContext(ctx context.Context, plugins *Set, properties map[string]string) *InitContext {
+	if properties == nil {
+		properties = map[string]string{}
+	}
 	return &InitContext{
-		Context: ctx,
-		Root:    filepath.Join(root, r.URI()),
-		State:   filepath.Join(state, r.URI()),
+		Context:    ctx,
+		Properties: properties,
 		Meta: &Meta{
 			Exports: map[string]string{},
 		},
@@ -62,16 +59,16 @@ func (i *InitContext) Get(t Type) (interface{}, error) {
 // Meta contains information gathered from the registration and initialization
 // process.
 type Meta struct {
-	Platforms    []ocispec.Platform // platforms supported by plugin
-	Exports      map[string]string  // values exported by plugin
-	Capabilities []string           // feature switches for plugin
+	Platforms    []imagespec.Platform // platforms supported by plugin
+	Exports      map[string]string    // values exported by plugin
+	Capabilities []string             // feature switches for plugin
 }
 
 // Plugin represents an initialized plugin, used with an init context.
 type Plugin struct {
-	Registration *Registration // registration, as initialized
-	Config       interface{}   // config, as initialized
-	Meta         *Meta
+	Registration Registration // registration, as initialized
+	Config       interface{}  // config, as initialized
+	Meta         Meta
 
 	instance interface{}
 	err      error // will be set if there was an error initializing the plugin
@@ -115,7 +112,7 @@ func (ps *Set) Add(p *Plugin) error {
 	} else if _, idok := byID[p.Registration.ID]; !idok {
 		byID[p.Registration.ID] = p
 	} else {
-		return fmt.Errorf("plugin %v already initialized: %w", p.Registration.URI(), errdefs.ErrAlreadyExists)
+		return fmt.Errorf("plugin add failed for %s: %w", p.Registration.URI(), ErrPluginInitialized)
 	}
 
 	ps.ordered = append(ps.ordered, p)
@@ -127,7 +124,7 @@ func (ps *Set) Get(t Type) (interface{}, error) {
 	for _, v := range ps.byTypeAndID[t] {
 		return v.Instance()
 	}
-	return nil, fmt.Errorf("no plugins registered for %s: %w", t, errdefs.ErrNotFound)
+	return nil, fmt.Errorf("no plugins registered for %s: %w", t, ErrPluginNotFound)
 }
 
 // GetAll returns all initialized plugins
@@ -153,7 +150,7 @@ func (i *InitContext) GetByID(t Type, id string) (interface{}, error) {
 	}
 	p, ok := ps[id]
 	if !ok {
-		return nil, fmt.Errorf("no %s plugins with id %s: %w", t, id, errdefs.ErrNotFound)
+		return nil, fmt.Errorf("no %s plugins with id %s: %w", t, id, ErrPluginNotFound)
 	}
 	return p.Instance()
 }
@@ -162,7 +159,7 @@ func (i *InitContext) GetByID(t Type, id string) (interface{}, error) {
 func (i *InitContext) GetByType(t Type) (map[string]*Plugin, error) {
 	p, ok := i.plugins.byTypeAndID[t]
 	if !ok {
-		return nil, fmt.Errorf("no plugins registered for %s: %w", t, errdefs.ErrNotFound)
+		return nil, fmt.Errorf("no plugins registered for %s: %w", t, ErrPluginNotFound)
 	}
 
 	return p, nil

dynamic/dynamic.go

@@ -0,0 +1,37 @@
+/*
+   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 dynamic
+
+import "fmt"
+
+// Load loads all plugins at the provided path into containerd.
+//
+// Load is currently only implemented on non-static, non-gccgo builds for amd64
+// and arm64, and plugins must be built with the exact same version of Go as
+// containerd itself.
+func Load(path string) (err error) {
+	defer func() {
+		if v := recover(); v != nil {
+			rerr, ok := v.(error)
+			if !ok {
+				rerr = fmt.Errorf("%s", v)
+			}
+			err = rerr
+		}
+	}()
+	return loadPlugins(path)
+}

plugin_supported.go dynamic/dynamic_supported.goplugin_supported.go renamed to dynamic/dynamic_supported.go

@@ -16,7 +16,7 @@
    limitations under the License.
 */
 
-package plugin
+package dynamic
 
 import (
 	"fmt"

plugin_unsupported.go dynamic/dynamic_unsupported.goplugin_unsupported.go renamed to dynamic/dynamic_unsupported.go

@@ -16,7 +16,7 @@
    limitations under the License.
 */
 
-package plugin
+package dynamic
 
 // loadPlugins is not supported;
 //