constellation/kms/storage/gcloudstorage.go
Daniel Weiße 2622d3c39d Add GCP storage unit tests
Signed-off-by: Daniel Weiße <dw@edgeless.systems>
2022-04-01 09:41:15 +02:00

125 lines
3.7 KiB
Go

package storage
import (
"context"
"errors"
"io"
"cloud.google.com/go/storage"
"google.golang.org/api/option"
)
type gcpStorageAPI interface {
Attrs(ctx context.Context, bucketName string) (*storage.BucketAttrs, error)
Close() error
CreateBucket(ctx context.Context, bucketName, projectID string, attrs *storage.BucketAttrs) error
NewWriter(ctx context.Context, bucketName, objectName string) io.WriteCloser
NewReader(ctx context.Context, bucketName, objectName string) (io.ReadCloser, error)
}
type wrappedGCPClient struct {
*storage.Client
}
func (c *wrappedGCPClient) Attrs(ctx context.Context, bucketName string) (*storage.BucketAttrs, error) {
return c.Client.Bucket(bucketName).Attrs(ctx)
}
func (c *wrappedGCPClient) CreateBucket(ctx context.Context, bucketName, projectID string, attrs *storage.BucketAttrs) error {
return c.Client.Bucket(bucketName).Create(ctx, projectID, attrs)
}
func (c *wrappedGCPClient) NewWriter(ctx context.Context, bucketName, objectName string) io.WriteCloser {
return c.Client.Bucket(bucketName).Object(objectName).NewWriter(ctx)
}
func (c *wrappedGCPClient) NewReader(ctx context.Context, bucketName, objectName string) (io.ReadCloser, error) {
return c.Client.Bucket(bucketName).Object(objectName).NewReader(ctx)
}
// GoogleCloudStorage is an implementation of the Storage interface, storing keys in Google Cloud Storage buckets.
type GoogleCloudStorage struct {
newClient func(ctx context.Context, opts ...option.ClientOption) (gcpStorageAPI, error)
projectID string
bucketName string
opts []option.ClientOption
}
// NewGoogleCloudStorage creates a Storage client for Google Cloud Storage: https://cloud.google.com/storage/docs/
//
// The parameter bucketOptions is optional, if not present default options will be created.
func NewGoogleCloudStorage(ctx context.Context, projectID, bucketName string, bucketOptions *storage.BucketAttrs, opts ...option.ClientOption) (*GoogleCloudStorage, error) {
s := &GoogleCloudStorage{
newClient: gcpStorageClientFactory,
projectID: projectID,
bucketName: bucketName,
opts: opts,
}
// Make sure the storage bucket exists, if not create it
if err := s.createContainerOrContinue(ctx, bucketOptions); err != nil {
return nil, err
}
return s, nil
}
// Get returns a DEK from Google Cloud Storage by key ID.
func (s *GoogleCloudStorage) Get(ctx context.Context, keyID string) ([]byte, error) {
client, err := s.newClient(ctx, s.opts...)
if err != nil {
return nil, err
}
defer client.Close()
reader, err := client.NewReader(ctx, s.bucketName, keyID)
if err != nil {
if errors.Is(err, storage.ErrObjectNotExist) {
return nil, ErrDEKUnset
}
return nil, err
}
defer reader.Close()
return io.ReadAll(reader)
}
// Put saves a DEK to Google Cloud Storage by key ID.
func (s *GoogleCloudStorage) Put(ctx context.Context, keyID string, data []byte) error {
client, err := s.newClient(ctx, s.opts...)
if err != nil {
return err
}
defer client.Close()
writer := client.NewWriter(ctx, s.bucketName, keyID)
defer writer.Close()
_, err = writer.Write(data)
return err
}
func (s *GoogleCloudStorage) createContainerOrContinue(ctx context.Context, bucketOptions *storage.BucketAttrs) error {
client, err := s.newClient(ctx, s.opts...)
if err != nil {
return err
}
defer client.Close()
if _, err := client.Attrs(ctx, s.bucketName); errors.Is(err, storage.ErrBucketNotExist) {
return client.CreateBucket(ctx, s.bucketName, s.projectID, bucketOptions)
} else if err != nil {
return err
}
return nil
}
func gcpStorageClientFactory(ctx context.Context, opts ...option.ClientOption) (gcpStorageAPI, error) {
client, err := storage.NewClient(ctx, opts...)
if err != nil {
return nil, err
}
return &wrappedGCPClient{client}, nil
}