| // Copyright 2018 Google LLC |
| // |
| // 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 preloader |
| |
| import ( |
| "context" |
| "fmt" |
| "io" |
| "path/filepath" |
| |
| "cloud.google.com/go/storage" |
| "google.golang.org/api/iterator" |
| ) |
| |
| const ( |
| managedDir = "cos-customizer" |
| ) |
| |
| // gcsManager provides a simple key/value interface to a GCS directory, where keys are object paths |
| // and values are object data. |
| type gcsManager struct { |
| gcsClient *storage.Client |
| gcsBucket, gcsDir string |
| } |
| |
| func (m *gcsManager) managedDir() string { |
| return filepath.Join(m.gcsDir, managedDir) |
| } |
| |
| // managedDirURL gets the GCS URL of the directory being managed by the GCSManager. |
| func (m *gcsManager) managedDirURL() string { |
| return fmt.Sprintf("gs://%s/%s", m.gcsBucket, m.managedDir()) |
| } |
| |
| func (m *gcsManager) objectPath(name string) string { |
| return filepath.Join(m.managedDir(), name) |
| } |
| |
| // store stores the given data in the given file. The file should be given as a path |
| // relative to the managed directory. |
| func (m *gcsManager) store(ctx context.Context, r io.Reader, name string) error { |
| object := m.objectPath(name) |
| w := m.gcsClient.Bucket(m.gcsBucket).Object(object).NewWriter(ctx) |
| if _, err := io.Copy(w, r); err != nil { |
| return err |
| } |
| return w.Close() |
| } |
| |
| // url gets the GCS URL of the given file. The file should be given as a path |
| // relative to the managed directory. |
| func (m *gcsManager) url(name string) string { |
| object := m.objectPath(name) |
| return fmt.Sprintf("gs://%s/%s", m.gcsBucket, object) |
| } |
| |
| // cleanup cleans up the managed directory. |
| func (m *gcsManager) cleanup(ctx context.Context) error { |
| q := &storage.Query{Prefix: m.managedDir()} |
| it := m.gcsClient.Bucket(m.gcsBucket).Objects(ctx, q) |
| var objects []string |
| for { |
| objAttrs, err := it.Next() |
| if err == iterator.Done { |
| break |
| } |
| if err != nil { |
| return err |
| } |
| objects = append(objects, objAttrs.Name) |
| } |
| for _, object := range objects { |
| if err := m.gcsClient.Bucket(m.gcsBucket).Object(object).Delete(ctx); err != nil { |
| return err |
| } |
| } |
| return nil |
| } |