containerd/plugin.go

112 lines
1.9 KiB
Go

package containerd
import (
"fmt"
"path/filepath"
"plugin"
"runtime"
"sync"
"github.com/docker/containerd/content"
"golang.org/x/net/context"
"google.golang.org/grpc"
)
type PluginType int
const (
RuntimePlugin PluginType = iota + 1
GRPCPlugin
)
type Registration struct {
Type PluginType
Config interface{}
Init func(*InitContext) (interface{}, error)
}
type InitContext struct {
Root string
State string
Runtimes map[string]Runtime
Store *content.Store
Config interface{}
Context context.Context
}
type Service interface {
Register(*grpc.Server) error
}
var register = struct {
sync.Mutex
r map[string]*Registration
}{
r: make(map[string]*Registration),
}
// Load loads all plugins at the provided that into containerd
func Load(path string) (err error) {
defer func() {
if v := recover(); v != nil {
rerr, ok := v.(error)
if !ok {
panic(v)
}
err = rerr
}
}()
return loadPlugins(path)
}
func Register(name string, r *Registration) error {
register.Lock()
defer register.Unlock()
if _, ok := register.r[name]; ok {
return fmt.Errorf("plugin already registered as %q", name)
}
register.r[name] = r
return nil
}
func Registrations() map[string]*Registration {
return register.r
}
// loadPlugins loads all plugins for the OS and Arch
// that containerd is built for inside the provided path
func loadPlugins(path string) error {
abs, err := filepath.Abs(path)
if err != nil {
return err
}
pattern := filepath.Join(abs, fmt.Sprintf(
"*-%s-%s.%s",
runtime.GOOS,
runtime.GOARCH,
getLibExt(),
))
libs, err := filepath.Glob(pattern)
if err != nil {
return err
}
for _, lib := range libs {
if _, err := plugin.Open(lib); err != nil {
return err
}
}
return nil
}
// getLibExt returns a platform specific lib extension for
// the platform that containerd is running on
func getLibExt() string {
switch runtime.GOOS {
case "windows":
return "dll"
default:
return "so"
}
}