chenhg5/cc-connect · error

wecom-ws: empty aeskey

Error message

wecom-ws: empty aeskey

What it means

Guard at the top of decodeWeComAESKey: the aeskey string accompanying an inbound WeCom media message (image/file) is empty, so there is no key to decrypt the downloaded ciphertext. The key normally arrives on every media callback body, so an empty value means a malformed or unexpected callback payload.

Source

Thrown at platform/wecom/websocket_media.go:207

		if body.MsgType == "file" && body.File != nil {
			appendFile(&current, body.File.URL, body.File.Aeskey, false)
		}
		if body.MsgType == "image" && body.Image != nil {
			appendImage(&current, body.Image.URL, body.Image.Aeskey, false)
		}
	}
	walkQuote(body.Quote)
	return current, quoted
}

// decodeWeComAESKey normalizes and decodes the aeskey from WeCom WS callbacks.
// The server may send standard Base64, URL-safe Base64 (- _), omit padding, insert
// whitespace, or (rarely) a 64-char hex string. Node's Buffer.from(s, 'base64') is more
// permissive than Go's StdEncoding; we mirror common cases so decryption matches the SDK.
func decodeWeComAESKey(aesKey string) ([]byte, error) {
	s := strings.TrimSpace(aesKey)
	if s == "" {
		return nil, fmt.Errorf("wecom-ws: empty aeskey")
	}
	var b strings.Builder
	b.Grow(len(s))
	for i := 0; i < len(s); i++ {
		switch s[i] {
		case '\n', '\r', ' ', '\t':
			continue
		default:
			b.WriteByte(s[i])
		}
	}
	s = b.String()

	if len(s) == 64 && isHexString(s) {
		key, err := hex.DecodeString(s)
		if err != nil {
			return nil, fmt.Errorf("wecom-ws: decode aeskey hex: %w", err)
		}

View on GitHub (pinned to 4000b2338a)

Solutions

1. Skip the media item and notify/log rather than retrying — the callback payload itself is incomplete
2. Verify the callback schema version expected from the WeCom AI-Bot WS feed
3. Guard upstream in the media walker so attachments without aeskey are ignored individually without failing the whole message

When it happens

Trigger: Thrown at platform/wecom/websocket_media.go:207 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/1a0f95c7645920e7. Report an issue: GitHub.