text: // Copyright 2018 Google LLC All Rights Reserved.
  //
  // 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 remote
  
  import (
  	"fmt"
  	"io/ioutil"
  	"net/http"
  	"net/url"
  
  	"github.com/google/go-containerregistry/pkg/authn"
  	"github.com/google/go-containerregistry/pkg/name"
  	"github.com/google/go-containerregistry/pkg/v1/remote/transport"
  )
  
  // Delete removes the specified image reference from the remote registry.
  func Delete(ref name.Reference, auth authn.Authenticator, t http.RoundTripper) error {
  	scopes := []string{ref.Scope(transport.DeleteScope)}
  	tr, err := transport.New(ref.Context().Registry, auth, t, scopes)
  	if err != nil {
  		return err
  	}
  	c := &http.Client{Transport: tr}
  
  	u := url.URL{
  		Scheme: ref.Context().Registry.Scheme(),
  		Host:   ref.Context().RegistryStr(),
  		Path:   fmt.Sprintf("/v2/%s/manifests/%s", ref.Context().RepositoryStr(), ref.Identifier()),
  	}
  
  	req, err := http.NewRequest(http.MethodDelete, u.String(), nil)
  	if err != nil {
  		return err
  	}
  
  	resp, err := c.Do(req)
  	if err != nil {
  		return err
  	}
  	defer resp.Body.Close()
  
  	switch resp.StatusCode {
  	case http.StatusOK, http.StatusAccepted:
  		return nil
  	default:
  		b, err := ioutil.ReadAll(resp.Body)
  		if err != nil {
  			return err
  		}
  		return fmt.Errorf("unrecognized status code during DELETE: %v; %v", resp.Status, string(b))
  	}
  }
  