siyuan-note/siyuan · warning

parse svg failed: %w

Error message

parse svg failed: %w

What it means

SanitizeSVG runs an XML decoder in Strict mode and streams tokens via RawToken. Any XML well-formedness error (invalid syntax, undeclared entity, bad encoding, mismatched tag) is wrapped with %w and returned. SVGs that are valid HTML but not valid XML (unquoted attributes, HTML entities like  , unclosed tags) will trip this.

Source

Thrown at kernel/util/misc.go:358

	decoder := xml.NewDecoder(strings.NewReader(svgInput))
	decoder.Strict = true

	var buf bytes.Buffer
	encoder := xml.NewEncoder(&buf)
	rootSeen := false
	rootClosed := false
	depth := 0
	skipDepth := 0
	tokenCount := 0
	var elementStack []xml.Name

	for {
		token, err := decoder.RawToken()
		if err == io.EOF {
			break
		}
		if err != nil {
			return "", fmt.Errorf("parse svg failed: %w", err)
		}
		tokenCount++
		if tokenCount > maxSVGTokens {
			return "", fmt.Errorf("svg contains too many tokens")
		}

		switch typed := token.(type) {
		case xml.StartElement:
			elementStack = append(elementStack, typed.Name)
			depth++
			if depth > maxSVGDepth {
				return "", fmt.Errorf("svg nesting depth exceeds %d", maxSVGDepth)
			}
			if rootClosed {
				return "", fmt.Errorf("svg contains multiple root elements")
			}
			if !rootSeen {
				if !strings.EqualFold(typed.Name.Local, "svg") {

View on GitHub (pinned to 251596fc0d)

Solutions

1. Open the SVG in a strict XML validator and fix well-formedness errors (quote all attributes, escape &, close all tags).
2. Replace HTML entities ( ) with numeric XML entities ( ) or literal characters.
3. Re-save from an editor that emits well-formed XML (e.g. Inkscape 'Optimized SVG').
4. Ensure UTF-8 bytes match the <?xml encoding="utf-8"?> declaration, or omit the declaration.

Example fix

<!-- before -->
<svg><rect width=100 height=50 fill="red">&copy;</svg>

<!-- after -->
<svg xmlns="http://www.w3.org/2000/svg"><rect width="100" height="50" fill="red"/>&#169;</svg>

dec := xml.NewDecoder(strings.NewReader(svg))
dec.Strict = true
if _, err := dec.Token(); err != nil {
    return errors.New("svg is not well-formed XML: " + err.Error())
}

clean, err := util.SanitizeSVG(raw)
if err != nil {
    logging.LogWarnf("skip non-well-formed SVG: %s", err)
    return fallback // raw <img src> or placeholder
}

When it happens

Trigger: Inserting/previewing an SVG asset that is not well-formed XML: unquoted attributes, HTML entities (&nbsp; &copy;), missing closing tags, BOM or <?xml encoding mismatch, namespace prefixes without declaration, stray < or & in text.

Common situations: SVG exported from design tools with HTML quirks; SVGs copied from web pages with HTML entities; hand-authored SVG with typos; SVG whose encoding declaration disagrees with the file bytes.

Related errors

• copy unused asset [%s] to history failed: %w
• remove unused asset [%s] failed: %w
• Tesseract OCR is not installed or configured, please refer t
• SVG images are not accepted by multimodal models
• image attachment request limit exceeded: at most %d images a

AI-assisted analysis of siyuan-note/siyuan@251596fc0d (2026-08-12). Data as JSON: /api/errors/aee9595fac752222. Report an issue: GitHub.