chenhg5/cc-connect · error

googlechat: SendImage: invalid reply context type %T

Error message

googlechat: SendImage: invalid reply context type %T

What it means

SendImage expects its reply-context argument to be the concrete type googlechat.replyContext. Because the core.ImageSender interface passes it as any, a context created by another platform (or any other value) fails the type assertion and triggers this error naming the offending dynamic type.

Source

Thrown at platform/googlechat/googlechat.go:564

	if err != nil {
		return err
	}
	if _, err := io.Copy(io.Discard, resp.Body); err != nil {
		_ = resp.Body.Close()
		return fmt.Errorf("googlechat: drain attachment create response body: %w", err)
	}
	if err := resp.Body.Close(); err != nil {
		return fmt.Errorf("googlechat: close attachment create response body: %w", err)
	}
	return nil
}

// SendImage uploads an image and posts it as a Chat message attachment.
// Implements core.ImageSender.
func (p *Platform) SendImage(ctx context.Context, rctx any, img core.ImageAttachment) error {
	rc, ok := rctx.(replyContext)
	if !ok {
		return fmt.Errorf("googlechat: SendImage: invalid reply context type %T", rctx)
	}
	return p.postAttachment(ctx, rc,
		coalesce(img.FileName, "image.png"),
		coalesce(img.MimeType, "image/png"),
		img.Data)
}

// SendFile uploads a file and posts it as a Chat message attachment.
// Implements core.FileSender.
func (p *Platform) SendFile(ctx context.Context, rctx any, file core.FileAttachment) error {
	rc, ok := rctx.(replyContext)
	if !ok {
		return fmt.Errorf("googlechat: SendFile: invalid reply context type %T", rctx)
	}
	return p.postAttachment(ctx, rc,
		coalesce(file.FileName, "attachment"),
		coalesce(file.MimeType, "application/octet-stream"),
		file.Data)

View on GitHub (pinned to 4000b2338a)

Solutions

1. Only pass the reply context value returned by this googlechat platform (e.g. from Reply/message handling)
2. Add a type assertion/check at the call site before invoking SendImage
3. If writing cross-platform code, obtain rctx from the same platform instance you call SendImage on

Example fix

// before
p.SendImage(ctx, someOtherPlatformCtx, img)
// after
if gcCtx, ok := someOtherPlatformCtx.(googlechat.ReplyContext); ok {
    p.SendImage(ctx, gcCtx, img)
}

func isGoogleChatReplyContext(rctx any) bool { _, ok := rctx.(replyContext); return ok }

if err := p.SendImage(ctx, rctx, img); err != nil {
    var tErr *typeMismatchError
    if errors.As(err, &tErr) { slog.Error("wrong reply context type", "got", fmt.Sprintf("%T", rctx)) }
    return err
}

When it happens

Trigger: Passing a reply context obtained from a different platform's adapter, a nil value, or a manually-built struct of the wrong type into SendImage.

Common situations: Mixing platform adapters in a multi-platform deployment; caching reply contexts across platforms; refactor changing the context type without updating callers.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

• googlechat: SendFile: invalid reply context type %T
• dingtalk: SendImage: invalid reply context type %T
• googlechat: invalid reply context type %T
• max: unexpected replyCtx type %T
• qqbot: invalid reply context

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/dcd96dd1b3a6dfac. Report an issue: GitHub.