chenhg5/cc-connect · error

googlechat: upload: empty resourceName in response

Error message

googlechat: upload: empty resourceName in response

What it means

Returned by uploadAttachment when the Chat upload response decodes successfully but attachmentDataRef.resourceName is empty — the server acknowledged the upload but did not return the attachment reference needed to send the message. This indicates an unexpected/empty API response for the upload. It surfaces via postAttachment from SendImage/SendFile.

Source

Thrown at platform/googlechat/googlechat.go:504

		return "", err
	}
	defer func() {
		if err := resp.Body.Close(); err != nil {
			slog.Warn("googlechat: close upload response body", "error", err)
		}
	}()

	var result struct {
		AttachmentDataRef struct {
			ResourceName string `json:"resourceName"`
		} `json:"attachmentDataRef"`
	}
	defer func() { _, _ = io.Copy(io.Discard, resp.Body) }()
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		return "", fmt.Errorf("googlechat: upload: decode response: %w", err)
	}
	if result.AttachmentDataRef.ResourceName == "" {
		return "", fmt.Errorf("googlechat: upload: empty resourceName in response")
	}
	return result.AttachmentDataRef.ResourceName, nil
}

// buildAttachmentRequest builds the Chat REST API URL and JSON body to post a
// message that references an already-uploaded attachment (by resource name).
// Threading behaviour mirrors buildSendRequest.
func buildAttachmentRequest(rc replyContext, resourceName string) (string, []byte, error) {
	body := map[string]any{
		"attachment": []map[string]any{
			{"attachmentDataRef": map[string]any{"resourceName": resourceName}},
		},
	}
	applyThread(body, rc)
	b, err := json.Marshal(body)
	if err != nil {
		return "", nil, fmt.Errorf("googlechat: marshal attachment body: %w", err)
	}

View on GitHub (pinned to 4000b2338a)

Solutions

1. Log the full decoded response to see what fields the server actually returned.
2. Verify the OAuth scopes cover media upload with send permission.
3. Retry the upload — transient server-side issues can yield empty refs.
4. Check the Google Workspace API release notes / issue tracker for Chat upload response schema changes and update the library.

// avoid zero-byte uploads which can produce empty refs
fi, err := os.Stat(path)
if err != nil || fi.Size() == 0 {
    return fmt.Errorf("refusing to upload empty or missing file %q", path)
}

name, err := p.SendFile(ctx, target, path)
if err != nil && strings.Contains(err.Error(), "empty resourceName") {
    time.Sleep(2 * time.Second)
    return p.SendFile(ctx, target, path)
}

When it happens

Trigger: Calling SendImage()/SendFile(); the upload endpoint responds with JSON lacking attachmentDataRef.resourceName — e.g. the API changed its response shape or an edge response omitted the ref.

Common situations: Google Chat API behavior changes; uploading with a scope the API accepts only partially (auth issues); zero-byte or unusual payloads causing the server to skip the attachment ref.

Understand the failure class

Background: "empty response", "returned no data", "empty embeddings": what HTTP 200-with-empty-body errors mean across libraries — this error's family across 36 libraries.

Related errors

• googlechat: upload: decode response: %w
• googlechat: upload: create metadata part: %w
• googlechat: upload: encode metadata: %w
• googlechat: upload: create media part: %w
• googlechat: upload: write media: %w

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/0cd7d58d49860ff2. Report an issue: GitHub.