GCS Extra Functionalities

gcs/client/client.go

@@ -18,15 +18,18 @@ package client
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
 	"log"
 	"os"
 	"strings"
+	"sync"
 	"time"
 
 	"golang.org/x/oauth2/google"
+	"google.golang.org/api/iterator"
 
 	"cloud.google.com/go/storage"
 
@@ -37,6 +40,15 @@ import (
 // client disallow an attempted write operation.
 var ErrInvalidROWriteOperation = errors.New("the client operates in read only mode. Change 'credentials_source' parameter value ")
 
+// To enforce concurent go routine numbers during delete-recursive operation
+const maxConcurrency = 10
+
+type BlobProperties struct {
+	ETag          string    `json:"etag,omitempty"`
+	LastModified  time.Time `json:"last_modified,omitempty"`
+	ContentLength int64     `json:"content_length,omitempty"`
+}
+
 // GCSBlobstore encapsulates interaction with the GCS blobstore
 type GCSBlobstore struct {
 	authenticatedGCS *storage.Client
@@ -68,6 +80,11 @@ func (client *GCSBlobstore) getObjectHandle(gcs *storage.Client, src string) *st
 	return handle
 }
 
+func (client *GCSBlobstore) getBucketHandle(gcs *storage.Client) *storage.BucketHandle {
+	handle := gcs.Bucket(client.config.BucketName)
+	return handle
+}
+
 // New returns a GCSBlobstore configured to operate using the given config
 //
 // non-nil error is returned on invalid Client or config. If the configuration
@@ -246,21 +263,160 @@ func (client *GCSBlobstore) Sign(id string, action string, expiry time.Duration)
 }
 
 func (client *GCSBlobstore) List(prefix string) ([]string, error) {
-	return nil, errors.New("not implemented")
+	if prefix != "" {
+		log.Printf("Listing objects in bucket %s with prefix '%s'\n", client.config.BucketName, prefix)
+	} else {
+		log.Printf("Listing objects in bucket %s\n", client.config.BucketName)
+	}
+	if client.readOnly() {
+		return nil, ErrInvalidROWriteOperation
+	}
+
+	bh := client.getBucketHandle(client.authenticatedGCS)
+
+	it := bh.Objects(context.Background(), &storage.Query{Prefix: prefix})
+
+	var names []string
+	for {
+		attr, err := it.Next()
+		if err == iterator.Done {
+			break
+		}
+
+		if err != nil {
+			return nil, err
+		}
+
+		names = append(names, attr.Name)
+	}
+
+	return names, nil
+
 }
 
 func (client *GCSBlobstore) Copy(srcBlob string, dstBlob string) error {
-	return errors.New("not implemented")
+	log.Printf("copying an object from %s to %s\n", srcBlob, dstBlob)
+	if client.readOnly() {
+		return ErrInvalidROWriteOperation
+	}
+
+	srcHandle := client.getObjectHandle(client.authenticatedGCS, srcBlob)
+	dstHandle := client.getObjectHandle(client.authenticatedGCS, dstBlob)
+
+	_, err := dstHandle.CopierFrom(srcHandle).Run(context.Background())
+	if err != nil {
+		return fmt.Errorf("copying object: %w", err)
+	}
+	return nil
 }
 
 func (client *GCSBlobstore) Properties(dest string) error {
-	return errors.New("not implemented")
+	log.Printf("Getting properties for object %s/%s\n", client.config.BucketName, dest)
+	if client.readOnly() {
+		return ErrInvalidROWriteOperation
+	}
+	oh := client.getObjectHandle(client.authenticatedGCS, dest)
+	attr, err := oh.Attrs(context.Background())
+
+	if err != nil {
+		return fmt.Errorf("getting attributes: %w", err)
+	}
+
+	props := BlobProperties{
+		ETag:          strings.Trim(attr.Etag, `"`),
+		LastModified:  attr.Updated,
+		ContentLength: attr.Size,
+	}
+
+	output, err := json.MarshalIndent(props, "", "  ")
+	if err != nil {
+		return fmt.Errorf("failed to marshal blob properties: %w", err)
+	}
+
+	fmt.Println(string(output))
+	return nil
 }
 
 func (client *GCSBlobstore) EnsureStorageExists() error {
-	return errors.New("not implemented")
+	log.Printf("Ensuring bucket '%s' exists\n", client.config.BucketName)
+	if client.readOnly() {
+		return ErrInvalidROWriteOperation
+	}
+	ctx := context.Background()
+	bh := client.getBucketHandle(client.authenticatedGCS)
+
+	_, err := bh.Attrs(ctx)
+	if errors.Is(err, storage.ErrBucketNotExist) {
+		battr := &storage.BucketAttrs{Name: client.config.BucketName}
+		if client.config.StorageClass != "" {
+			battr.StorageClass = client.config.StorageClass
+		}
+
+		projectID, err := extractProjectID(ctx, client.config)
+		if err != nil {
+			return fmt.Errorf("extracting project ID: %w", err)
+		}
+
+		err = bh.Create(ctx, projectID, battr)
+		if err != nil {
+			return fmt.Errorf("creating bucket: %w", err)
+		}
+		return nil
+	}
+	if err != nil {
+		return fmt.Errorf("checking bucket: %w", err)
+	}
+
+	return nil
 }
 
 func (client *GCSBlobstore) DeleteRecursive(prefix string) error {
-	return errors.New("not implemented")
+	if prefix != "" {
+		log.Printf("Deleting all objects in bucket %s with prefix '%s'\n",
+			client.config.BucketName, prefix)
+	} else {
+		log.Printf("Deleting all objects in bucket %s\n", client.config.BucketName)
+	}
+
+	if client.readOnly() {
+		return ErrInvalidROWriteOperation
+	}
+
+	names, err := client.List(prefix)
+	if err != nil {
+		return fmt.Errorf("listing objects: %w", err)
+	}
+
+	errChan := make(chan error, len(names))
+	semaphore := make(chan struct{}, maxConcurrency)
+	wg := &sync.WaitGroup{}
+	for _, n := range names {
+		name := n
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+
+			semaphore <- struct{}{}
+			defer func() { <-semaphore }()
+
+			err := client.getObjectHandle(client.authenticatedGCS, name).Delete(context.Background())
+			if err != nil && !errors.Is(err, storage.ErrObjectNotExist) {
+				errChan <- fmt.Errorf("deleting object %s: %w", name, err)
+			}
+		}()
+	}
+
+	wg.Wait()
+	close(errChan)
+
+	var errs []error
+	for err := range errChan {
+		errs = append(errs, err)
+	}
+
+	if len(errs) > 0 {
+		return errors.Join(errs...)
+	}
+
+	return nil
 }

gcs/client/sdk.go

@@ -18,7 +18,9 @@ package client
 
 import (
 	"context"
+	"encoding/json"
 	"errors"
+	"fmt"
 
 	"golang.org/x/oauth2/google"
 
@@ -52,3 +54,37 @@ func newStorageClients(ctx context.Context, cfg *config.GCSCli) (*storage.Client
 	}
 	return authenticatedClient, publicClient, err
 }
+
+func extractProjectID(ctx context.Context, cfg *config.GCSCli) (string, error) {
+	switch cfg.CredentialsSource {
+	case config.ServiceAccountFileCredentialsSource:
+		// Parse service account JSON to extract project_id
+		var serviceAccount struct {
+			ProjectID string `json:"project_id"`
+		}
+		if err := json.Unmarshal([]byte(cfg.ServiceAccountFile), &serviceAccount); err != nil {
+			return "", fmt.Errorf("parsing service account JSON: %w", err)
+		}
+		if serviceAccount.ProjectID == "" {
+			return "", errors.New("project_id not found in service account JSON")
+		}
+		return serviceAccount.ProjectID, nil
+
+	case config.DefaultCredentialsSource:
+		// Try to get project ID from default credentials
+		creds, err := google.FindDefaultCredentials(ctx, storage.ScopeFullControl)
+		if err != nil {
+			return "", fmt.Errorf("finding default credentials: %w", err)
+		}
+		if creds.ProjectID == "" {
+			return "", errors.New("project_id not found in default credentials")
+		}
+		return creds.ProjectID, nil
+
+	case config.NoneCredentialsSource:
+		return "", errors.New("cannot create bucket with read-only credentials")
+
+	default:
+		return "", errors.New("unknown credentials_source")
+	}
+}