diff --git a/pkg/transfer/plugins/plugins.go b/pkg/transfer/plugins/plugins.go new file mode 100644 index 000000000..2795f3885 --- /dev/null +++ b/pkg/transfer/plugins/plugins.go @@ -0,0 +1,63 @@ +/* + 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 plugins + +import ( + "fmt" + "reflect" + "sync" + + "github.com/containerd/containerd/errdefs" + "github.com/containerd/typeurl" +) + +var register = struct { + sync.RWMutex + r map[string]reflect.Type +}{} + +func Register(apiObject, transferObject interface{}) { + url, err := typeurl.TypeURL(apiObject) + if err != nil { + panic(err) + } + // Lock + register.Lock() + defer register.Unlock() + if register.r == nil { + register.r = map[string]reflect.Type{} + } + if _, ok := register.r[url]; ok { + panic(fmt.Sprintf("url already registered: %v", url)) + } + t := reflect.TypeOf(transferObject) + if t.Kind() == reflect.Ptr { + t = t.Elem() + } + register.r[url] = t +} + +func ResolveType(any typeurl.Any) (interface{}, error) { + register.RLock() + defer register.RUnlock() + if register.r != nil { + if t, ok := register.r[any.GetTypeUrl()]; ok { + return reflect.New(t).Interface(), nil + } + } + return nil, fmt.Errorf("%v not registered: %w", any.GetTypeUrl(), errdefs.ErrNotFound) +}