Method GetObject

storage/abs/reader.go:20–103

GetObject retrieves an object from Azure cloud

(
	ctx context.Context,
	reqHeader http.Header,
	container, key, _ string,
)

// GetObject retrieves an object from Azure cloud
func (s *Storage) GetObject(
	ctx context.Context,
	reqHeader http.Header,
	container, key, _ string,
) (*storage.ObjectReader, error) {
	// If either container or object name is empty, return 404
	if len(container) == 0 || len(key) == 0 {
		return storage.NewObjectNotFound(
			"invalid Azure Storage URL: container name or object key are empty",
		), nil
	}

	// Check if access to the container is allowed
	if !common.IsBucketAllowed(container, s.config.AllowedBuckets, s.config.DeniedBuckets) {
		return nil, fmt.Errorf("access to the Azure Storage container %s is denied", container)
	}

	header := make(http.Header)
	opts := &blob.DownloadStreamOptions{}

	// Check if this is partial request
	partial, err := parseRangeHeader(opts, reqHeader)
	if err != nil {
		return storage.NewObjectInvalidRange(), nil //nolint:nilerr
	}

	// Open the object
	result, err := s.client.DownloadStream(ctx, container, key, opts)
	if err != nil {
		//nolint:errorlint
		azError, ok := err.(*azcore.ResponseError)
		if !ok || azError.StatusCode < 100 || azError.StatusCode == http.StatusMovedPermanently {
			return nil, err
		} else {
			return storage.NewObjectError(azError.StatusCode, azError.Error()), nil
		}
	}

	// Pass through etag and last modified
	if result.ETag != nil {
		etag := string(*result.ETag)
		header.Set(httpheaders.Etag, etag)
	}

	if result.LastModified != nil {
		lastModified := result.LastModified.Format(http.TimeFormat)
		header.Set(httpheaders.LastModified, lastModified)
	}

	// Break early if response was not modified
	if !partial && common.IsNotModified(reqHeader, header) {
		if result.Body != nil {
			result.Body.Close()
		}

		return storage.NewObjectNotModified(header), nil
	}