101 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			101 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| package plugin
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| 
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| import (
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| 	"errors"
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| 	"fmt"
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| 	"sync"
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| 
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| 	"google.golang.org/grpc"
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| )
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| 
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| var (
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| 	ErrNoPluginType = errors.New("plugin: no type")
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| 	ErrNoPluginID   = errors.New("plugin: no id")
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| )
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| 
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| type PluginType string
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| 
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| const (
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| 	RuntimePlugin     PluginType = "io.containerd.runtime.v1"
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| 	GRPCPlugin        PluginType = "io.containerd.grpc.v1"
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| 	SnapshotPlugin    PluginType = "io.containerd.snapshotter.v1"
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| 	TaskMonitorPlugin PluginType = "io.containerd.monitor.v1"
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| 	DiffPlugin        PluginType = "io.containerd.differ.v1"
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| 	MetadataPlugin    PluginType = "io.containerd.metadata.v1"
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| 	ContentPlugin     PluginType = "io.containerd.content.v1"
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| )
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| 
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| type Registration struct {
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| 	Type     PluginType
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| 	ID       string
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| 	Config   interface{}
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| 	Requires []PluginType
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| 	Init     func(*InitContext) (interface{}, error)
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| 
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| 	added bool
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| }
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| 
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| func (r *Registration) URI() string {
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| 	return fmt.Sprintf("%s.%s", r.Type, r.ID)
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| }
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| 
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| type Service interface {
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| 	Register(*grpc.Server) error
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| }
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| 
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| var register = struct {
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| 	sync.Mutex
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| 	r []*Registration
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| }{}
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| 
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| // Load loads all plugins at the provided path into containerd
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| func Load(path string) (err error) {
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| 	defer func() {
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| 		if v := recover(); v != nil {
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| 			rerr, ok := v.(error)
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| 			if !ok {
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| 				rerr = fmt.Errorf("%s", v)
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| 			}
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| 			err = rerr
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| 		}
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| 	}()
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| 	return loadPlugins(path)
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| }
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| 
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| func Register(r *Registration) {
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| 	register.Lock()
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| 	defer register.Unlock()
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| 	if r.Type == "" {
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| 		panic(ErrNoPluginType)
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| 	}
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| 	if r.ID == "" {
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| 		panic(ErrNoPluginID)
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| 	}
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| 	register.r = append(register.r, r)
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| }
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| 
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| func Graph() (ordered []*Registration) {
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| 	for _, r := range register.r {
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| 		children(r.Requires, &ordered)
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| 		if !r.added {
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| 			ordered = append(ordered, r)
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| 			r.added = true
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| 		}
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| 	}
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| 	return ordered
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| }
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| 
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| func children(types []PluginType, ordered *[]*Registration) {
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| 	for _, t := range types {
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| 		for _, r := range register.r {
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| 			if r.Type == t {
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| 				children(r.Requires, ordered)
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| 				if !r.added {
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| 					*ordered = append(*ordered, r)
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| 					r.added = true
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| 				}
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| 			}
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| 		}
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| 	}
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| }
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